1
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Herrera A, Packer MM, Rosas-Lemus M, Minasov G, Chen J, Brumell JH, Satchell KJF. Vibrio MARTX toxin processing and degradation of cellular Rab GTPases by the cytotoxic effector Makes Caterpillars Floppy. Proc Natl Acad Sci U S A 2024; 121:e2316143121. [PMID: 38861595 PMCID: PMC11194500 DOI: 10.1073/pnas.2316143121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 04/19/2024] [Indexed: 06/13/2024] Open
Abstract
Vibrio vulnificus causes life-threatening wound and gastrointestinal infections, mediated primarily by the production of a Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin. The most commonly present MARTX effector domain, the Makes Caterpillars Floppy-like (MCF) toxin, is a cysteine protease stimulated by host adenosine diphosphate (ADP) ribosylation factors (ARFs) to autoprocess. Here, we show processed MCF then binds and cleaves host Ras-related proteins in brain (Rab) guanosine triphosphatases within their C-terminal tails resulting in Rab degradation. We demonstrate MCF binds Rabs at the same interface occupied by ARFs. Moreover, we show MCF preferentially binds to ARF1 prior to autoprocessing and is active to cleave Rabs only subsequent to autoprocessing. We then use structure prediction algorithms to demonstrate that structural composition, rather than sequence, determines Rab target specificity. We further determine a crystal structure of aMCF as a swapped dimer, revealing an alternative conformation we suggest represents the open, activated state of MCF with reorganized active site residues. The cleavage of Rabs results in Rab1B dispersal within cells and loss of Rab1B density in the intestinal tissue of infected mice. Collectively, our work describes an extracellular bacterial mechanism whereby MCF is activated by ARFs and subsequently induces the degradation of another small host guanosine triphosphatase (GTPase), Rabs, to drive organelle damage, cell death, and promote pathogenesis of these rapidly fatal infections.
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Affiliation(s)
- Alfa Herrera
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Megan M. Packer
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Monica Rosas-Lemus
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - George Minasov
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - Jiexi Chen
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
| | - John H. Brumell
- Cell Biology Program, The Hospital for Sick Children, Toronto, ONM5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ONM5G 0A4, Canada
- Institute of Medical Science, University of Toronto, Toronto, ONM5S 1A8, Canada
- SickKids Inflammatory Bowel Disease Centre, The Hospital for Sick Children, Toronto, ONM5G 0A4, Canada
| | - Karla J. F. Satchell
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL60611
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2
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Cobe BL, Dey S, Minasov G, Inniss N, Satchell KJF, Cianciotto NP. Bactericidal effectors of the Stenotrophomonas maltophilia type IV secretion system: functional definition of the nuclease TfdA and structural determination of TfcB. mBio 2024:e0119824. [PMID: 38832773 DOI: 10.1128/mbio.01198-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 04/28/2024] [Indexed: 06/05/2024] Open
Abstract
Stenotrophomonas maltophilia expresses a type IV protein secretion system (T4SS) that promotes contact-dependent killing of other bacteria and does so partly by secreting the effector TfcB. Here, we report the structure of TfcB, comprising an N-terminal domain similar to the catalytic domain of glycosyl hydrolase (GH-19) chitinases and a C-terminal domain for recognition and translocation by the T4SS. Utilizing a two-hybrid assay to measure effector interactions with the T4SS coupling protein VirD4, we documented the existence of five more T4SS substrates. One of these was protein 20845, an annotated nuclease. A S. maltophilia mutant lacking the gene for 20845 was impaired for killing Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Moreover, the cloned 20845 gene conferred robust toxicity, with the recombinant E. coli being rescued when 20845 was co-expressed with its cognate immunity protein. The 20845 effector was an 899 amino-acid protein, comprised of a GHH-nuclease domain in its N-terminus, a large central region of indeterminant function, and a C-terminus for secretion. Engineered variants of the 20845 gene that had mutations in the predicted catalytic site did not impede E. coli, indicating that the antibacterial effect of 20845 involves its nuclease activity. Using flow cytometry with DNA staining, we determined that 20845, but not its mutant variants, confers a loss in DNA content of target bacteria. Database searches revealed that uncharacterized homologs of 20845 occur within a range of bacteria. These data indicate that the S. maltophilia T4SS promotes interbacterial competition through the action of multiple toxic effectors, including a potent, novel DNase.IMPORTANCEStenotrophomonas maltophilia is a multi-drug-resistant, Gram-negative bacterium that is an emerging pathogen of humans. Patients with cystic fibrosis are particularly susceptible to S. maltophilia infection. In hospital water systems and various types of infections, S. maltophilia co-exists with other bacteria, including other pathogens such as Pseudomonas aeruginosa. We previously demonstrated that S. maltophilia has a functional VirB/D4 type VI protein secretion system (T4SS) that promotes contact-dependent killing of other bacteria. Since most work on antibacterial systems involves the type VI secretion system, this observation remains noteworthy. Moreover, S. maltophilia currently stands alone as a model for a human pathogen expressing an antibacterial T4SS. Using biochemical, genetic, and cell biological approaches, we now report both the discovery of a novel antibacterial nuclease (TfdA) and the first structural determination of a bactericidal T4SS effector (TfcB).
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Affiliation(s)
- Brandi L Cobe
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Supratim Dey
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Nicole Inniss
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Nicholas P Cianciotto
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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3
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Zhou P, G. C. B, Stolte F, Wu C. Use of CRISPR interference for efficient and rapid gene inactivation in Fusobacterium nucleatum. Appl Environ Microbiol 2024; 90:e0166523. [PMID: 38185820 PMCID: PMC10880640 DOI: 10.1128/aem.01665-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/27/2023] [Indexed: 01/09/2024] Open
Abstract
Gene inactivation by creating in-frame deletion mutations in Fusobacterium nucleatum is time consuming, and most fusobacterial strains are genetically intractable. Addressing these problems, we introduced a riboswitch-based inducible CRISPR interference (CRISPRi) system. This system employs the nuclease-inactive Streptococcus pyogenes Cas9 protein (dCas9), specifically guided to the gene of interest by a constantly expressed single-guide RNA (sgRNA). Mechanistically, this dCas9-sgRNA complex serves as an insurmountable roadblock for RNA polymerase, thus repressing the target gene transcription. Leveraging this system, we first examined two non-essential genes, ftsX and radD, which are pivotal for fusobacterial cytokinesis and coaggregation. Upon adding the inducer, theophylline, ftsX suppression caused filamentous cell formation akin to chromosomal ftsX deletion, while targeting radD significantly reduced RadD protein levels, abolishing RadD-mediated coaggregation. The system was then extended to probe essential genes bamA and ftsZ, which are vital for outer membrane biogenesis and cell division. Impressively, bamA suppression disrupted membrane integrity and bacterial separation, stalling growth, while ftsZ targeting yielded elongated cells in broth with compromised agar growth. Further studies on F. nucleatum clinical strain CTI-2 and Fusobacterium periodonticum revealed reduced indole synthesis when targeting tnaA. Moreover, silencing clpB in F. periodonticum decreased ClpB, increasing thermal sensitivity. In summary, our CRISPRi system streamlines gene inactivation across various fusobacterial strains.IMPORTANCEHow can we effectively investigate the gene functions in Fusobacterium nucleatum, given the dual challenges of gene inactivation and the inherent genetic resistance of many strains? Traditional methods have been cumbersome and often inadequate. Addressing this, our work introduces a novel inducible CRISPR interference (CRISPRi) system in which dCas9 expression is controlled at the translation level by a theophylline-responsive riboswitch unit, and single-guide RNA expression is driven by the robust, constitutive rpsJ promoter. This approach simplifies gene inactivation in the model organism (ATCC 23726) and extends its application to previously considered genetically intractable strains like CTI-2 and Fusobacterium periodonticum. With CRISPRi's potential, it is a pivotal tool for in-depth genetic studies into fusobacterial pathogenesis, potentially unlocking targeted therapeutic strategies.
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Affiliation(s)
- Peng Zhou
- Department of Microbiology & Molecular Genetics, The University of Texas Health Science Center, Houston, Texas, USA
| | - Bibek G. C.
- Department of Microbiology & Molecular Genetics, The University of Texas Health Science Center, Houston, Texas, USA
| | - Flynn Stolte
- Department of Microbiology & Molecular Genetics, The University of Texas Health Science Center, Houston, Texas, USA
| | - Chenggang Wu
- Department of Microbiology & Molecular Genetics, The University of Texas Health Science Center, Houston, Texas, USA
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4
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Kim Y, Maltseva N, Tesar C, Jedrzejczak R, Endres M, Ma H, Dugan HL, Stamper CT, Chang C, Li L, Changrob S, Zheng NY, Huang M, Ramanathan A, Wilson P, Michalska K, Joachimiak A. Epitopes recognition of SARS-CoV-2 nucleocapsid RNA binding domain by human monoclonal antibodies. iScience 2024; 27:108976. [PMID: 38327783 PMCID: PMC10847736 DOI: 10.1016/j.isci.2024.108976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/02/2023] [Accepted: 01/16/2024] [Indexed: 02/09/2024] Open
Abstract
Coronavirus nucleocapsid protein (NP) of SARS-CoV-2 plays a central role in many functions important for virus proliferation including packaging and protecting genomic RNA. The protein shares sequence, structure, and architecture with nucleocapsid proteins from betacoronaviruses. The N-terminal domain (NPRBD) binds RNA and the C-terminal domain is responsible for dimerization. After infection, NP is highly expressed and triggers robust host immune response. The anti-NP antibodies are not protective and not neutralizing but can effectively detect viral proliferation soon after infection. Two structures of SARS-CoV-2 NPRBD were determined providing a continuous model from residue 48 to 173, including RNA binding region and key epitopes. Five structures of NPRBD complexes with human mAbs were isolated using an antigen-bait sorting. Complexes revealed a distinct complement-determining regions and unique sets of epitope recognition. This may assist in the early detection of pathogens and designing peptide-based vaccines. Mutations that significantly increase viral load were mapped on developed, full length NP model, likely impacting interactions with host proteins and viral RNA.
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Affiliation(s)
- Youngchang Kim
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Natalia Maltseva
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Christine Tesar
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Robert Jedrzejczak
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Michael Endres
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Heng Ma
- Data Science and Learning Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Haley L. Dugan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Christopher T. Stamper
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Changsoo Chang
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Lei Li
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Siriruk Changrob
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Nai-Ying Zheng
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Min Huang
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
| | - Arvind Ramanathan
- Data Science and Learning Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Patrick Wilson
- Gale and Ira Drukier Institute for Children’s Health, Weill Cornell Medicine, New York, NY 10021, USA
| | - Karolina Michalska
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Andrzej Joachimiak
- Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60367, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60367, USA
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5
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Schütz A, Bernhard F, Berrow N, Buyel JF, Ferreira-da-Silva F, Haustraete J, van den Heuvel J, Hoffmann JE, de Marco A, Peleg Y, Suppmann S, Unger T, Vanhoucke M, Witt S, Remans K. A concise guide to choosing suitable gene expression systems for recombinant protein production. STAR Protoc 2023; 4:102572. [PMID: 37917580 PMCID: PMC10643540 DOI: 10.1016/j.xpro.2023.102572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/23/2023] [Accepted: 08/23/2023] [Indexed: 11/04/2023] Open
Abstract
This overview guides both novices and experienced researchers facing challenging targets to select the most appropriate gene expression system for producing a particular protein. By answering four key questions, readers can determine the most suitable gene expression system following a decision scheme. This guide addresses the most commonly used and accessible systems and provides brief descriptions of the main gene expression systems' key characteristics to assist decision making. Additionally, information has been included for selected less frequently used "exotic" gene expression systems.
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Affiliation(s)
- Anja Schütz
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Technology Platform for Protein Production & Characterization, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Frank Bernhard
- Institute of Biophysical Chemistry, Centre of Biomolecular Magnetic Resonance, Goethe-University of Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany
| | - Nick Berrow
- Protein Expression Core Facility, Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Johannes F Buyel
- Univeristy of Natural Resources and Life Sciences, Vienna (BOKU), Department of Biotechnology (DBT), Institute of Bioprocess Science and Engineering (IBSE), Muthgasse 18, 1190 Vienna, Austria
| | - Frederico Ferreira-da-Silva
- Instituto de Biologia Molecular e Celular (IBMC) and Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal
| | - Jurgen Haustraete
- VIB, Center for Inflammation Research & Ugent, Department of Biomedical Molecular Biology, Technologiepark-Zwijnaarde 71, 9052 Ghent, Belgium
| | - Joop van den Heuvel
- Helmholtz Centre for Infection Research (HZI), Department of Structure and Function of Proteins, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Jan-Erik Hoffmann
- Protein Chemistry Facility, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Str. 11, 44227 Dortmund, Germany
| | - Ario de Marco
- Laboratory of Environmental and Life Sciences, University of Nova Gorica, Vipavska Cesta 13, 5000 Nova Gorica, Slovenia
| | - Yoav Peleg
- Structural Proteomics Unit (SPU), Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sabine Suppmann
- Protein Expression and Purification Core Facility, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Tamar Unger
- Structural Proteomics Unit (SPU), Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Martine Vanhoucke
- BCCM/GeneCorner Plasmid Collection, Department of Biomedical Molecular Biology, Ghent University, Technologiepark-Zwijnaarde 71, 9052 Gent, Belgium
| | - Susanne Witt
- Centre for Structural Systems Biology (CSSB), University Medical Center Hamburg-Eppendorf (UKE), Notkestr. 85, 22607 Hamburg, Germany
| | - Kim Remans
- European Molecular Biology Laboratory (EMBL), Protein Expression and Purification Core Facility, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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Rosas-Lemus M, Dey S, Minasov G, Tan K, Anderson SM, Brunzelle J, Nocadello S, Shabalin I, Filippova E, Halavaty A, Kim Y, Maltseva N, Osipiuk J, Minor W, Joachimiak A, Savchenko A, Anderson WF, Satchell KJF. A high-throughput structural system biology approach to increase structure representation of proteins from Clostridioides difficile. Microbiol Resour Announc 2023; 12:e0050723. [PMID: 37747257 PMCID: PMC10586155 DOI: 10.1128/mra.00507-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/15/2023] [Indexed: 09/26/2023] Open
Abstract
Clostridioides difficile causes life-threatening gastrointestinal infections. It is a high-risk pathogen due to a lack of effective treatments, antimicrobial resistance, and a poorly conserved genomic core. Herein, we report 30 X-ray structures from a structure genomics pipeline spanning 13 years, representing 10.2% of the X-ray structures for this important pathogen.
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Affiliation(s)
- Monica Rosas-Lemus
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Supratim Dey
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Kemin Tan
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
| | - Spencer M. Anderson
- Northwestern Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois, USA
| | - Joseph Brunzelle
- Northwestern Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois, USA
| | - Salvatore Nocadello
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Ivan Shabalin
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ekaterina Filippova
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Andrei Halavaty
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Youngchang Kim
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
| | - Natalia Maltseva
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
| | - Jerzy Osipiuk
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
| | - Wladek Minor
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Andrzej Joachimiak
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
| | - Alexei Savchenko
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Wayne F. Anderson
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Karla J. F. Satchell
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
| | - Center for Structural Biology of Infectious Diseases team members
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Chicago, Illinois, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois, USA
- Northwestern Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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7
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Zhou P, G C B, Stolte F, Wu C. Use of CRISPR interference for efficient and rapid gene inactivation in Fusobacterium nucleatum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.19.558491. [PMID: 37781593 PMCID: PMC10541141 DOI: 10.1101/2023.09.19.558491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Gene inactivation via creating in-frame deletion mutations in Fusobacterium nucleatum is time-consuming, and most fusobacterial strains are genetically intractable. Addressing these problems, we introduced a riboswitch-based inducible CRISPRi system. This system employs the nuclease-inactive Streptococcus pyogenes Cas9 protein (dCas9), specifically guided to the gene of interest by a constantly expressed single guide RNA (sgRNA). Mechanistically, this dCas9-sgRNA complex serves as an insurmountable roadblock for RNA polymerase, thus repressing the target gene transcription. Leveraging this system, we first examined two non-essential genes, ftsX, and radD , pivotal for fusobacterial cytokinesis and coaggregation. Upon adding the inducer, theophylline, ftsX suppression caused filamentous cell formation akin to chromosomal ftsX deletion, while targeting radD significantly reduced RadD protein levels, abolishing coaggregation. The system was then extended to probe essential genes bamA and ftsZ , vital for outer membrane biogenesis and cell division. Impressively, bamA suppression disrupted membrane integrity and bacterial separation, stalling growth, while ftsZ- targeting yielded elongated cells in broth with compromised agar growth. Further studies on F. nucleatum clinical strain CTI-2 and Fusobacterium periodonticum revealed reduced indole synthesis when targeting tnaA . Moreover, silencing clpB in F. periodonticum decreased ClpB, increasing thermal sensitivity. In summary, our CRISPRi system streamlines gene inactivation across various fusobacterial strains. IMPORTANCE How can we effectively investigate the gene functions in Fusobacterium nucleatum , given the dual challenges of gene inactivation and the inherent genetic resistance of many strains? Traditional methods have been cumbersome and often inadequate. Addressing this, our work introduces a novel inducible CRISPRi system in which dCas9 expression is controlled at the translation level by a theophylline-responsive riboswitch unit, and sgRNA expression is driven by the robust, constitutive rpsJ promoter. This approach simplifies gene inactivation in the model organism (ATCC 23726) and extends its application to previously considered resistant strains like CTI-2 and Fusobacterium periodontium . With CRISPRi's potential, it is a pivotal tool for in-depth genetic studies into fusobacterial pathogenesis, potentially unlocking targeted therapeutic strategies.
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8
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Semper C, Savchenko A. Protein expression and purification of bioactive growth factors for use in cell culture and cellular agriculture. STAR Protoc 2023; 4:102351. [PMID: 37314918 PMCID: PMC10277608 DOI: 10.1016/j.xpro.2023.102351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/28/2023] [Accepted: 05/11/2023] [Indexed: 06/16/2023] Open
Abstract
Mitogenic growth factors are major cost drivers in serum-free media, contributing up to 95% of the total cost. Here, we present a streamlined workflow detailing cloning, expression testing, protein purification, and bioactivity screening that allows for low-cost production of bioactive growth factors including basic fibroblast growth factor and transforming growth factor β1. This generalized procedure can be used for multiple families of growth factors with minor modification, and the outputs are bioactive and suitable for cell culture applications. For complete details on the use and execution of this protocol, please refer to Venkatesan, et al.1.
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Affiliation(s)
- Cameron Semper
- Department of Microbiology, Immunology and Infectious Disease, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada.
| | - Alexei Savchenko
- Department of Microbiology, Immunology and Infectious Disease, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada; Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada.
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9
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Witkowska M, Jedrzejczak RP, Joachimiak A, Cavdar O, Malankowska A, Skowron PM, Zylicz-Stachula A. Promising approaches for the assembly of the catalytically active, recombinant Desulfomicrobium baculatum hydrogenase with substitutions at the active site. Microb Cell Fact 2023; 22:134. [PMID: 37479997 PMCID: PMC10362691 DOI: 10.1186/s12934-023-02127-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 06/17/2023] [Indexed: 07/23/2023] Open
Abstract
BACKGROUND Hydrogenases (H2ases) are metalloenzymes capable of the reversible conversion of protons and electrons to molecular hydrogen. Exploiting the unique enzymatic activity of H2ases can lead to advancements in the process of biohydrogen evolution and green energy production. RESULTS Here we created of a functional, optimized operon for rapid and robust production of recombinant [NiFe] Desulfomicrobium baculatum hydrogenase (Dmb H2ase). The conversion of the [NiFeSe] Dmb H2ase to [NiFe] type was performed on genetic level by site-directed mutagenesis. The native dmb operon includes two structural H2ase genes, coding for large and small subunits, and an additional gene, encoding a specific maturase (protease) that is essential for the proper maturation of the enzyme. Dmb, like all H2ases, needs intricate bio-production machinery to incorporate its crucial inorganic ligands and cofactors. Strictly anaerobic, sulfate reducer D. baculatum bacteria are distinct, in terms of their biology, from E. coli. Thus, we introduced a series of alterations within the native dmb genes. As a result, more than 100 elements, further compiled into 32 operon variants, were constructed. The initial requirement for a specific maturase was omitted by the artificial truncation of the large Dmb subunit. The assembly of the produced H2ase subunit variants was investigated both, in vitro and in vivo. This approach resulted in 4 recombinant [NiFe] Dmb enzyme variants, capable of H2 evolution. The aim of this study was to overcome the gene expression, protein biosynthesis, maturation and ligand loading bottlenecks for the easy, fast, and cost-effective delivery of recombinant [NiFe] H2ase, using a commonly available E. coli strains. CONCLUSION The optimized genetic constructs together with the developed growth and purification procedures appear to be a promising platform for further studies toward fully-active and O2 tolerant, recombinant [NiFeSe] Dmb H2ase, resembling the native Dmb enzyme. It could likely be achieved by selective cysteine to selenocysteine substitution within the active site of the [NiFe] Dmb variant.
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Affiliation(s)
- Malgorzata Witkowska
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Robert P Jedrzejczak
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Andrzej Joachimiak
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Onur Cavdar
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Anna Malankowska
- Department of Environmental Technology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Piotr M Skowron
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland
| | - Agnieszka Zylicz-Stachula
- Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, Gdansk, 80-308, Poland.
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10
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Herrera A, Packer MM, Rosas-Lemus M, Minasov G, Brummel JH, Satchell KJF. Vibrio MARTX toxin processing and degradation of cellular Rab GTPases by the cytotoxic effector Makes Caterpillars Floppy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.19.537381. [PMID: 37131655 PMCID: PMC10153396 DOI: 10.1101/2023.04.19.537381] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Vibrio vulnificus causes life threatening infections dependent upon the effectors released from the Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin. The Makes Caterpillars Floppy-like (MCF) cysteine protease effector is activated by host ADP ribosylation factors (ARFs), although the targets of processing activity were unknown. In this study we show MCF binds Ras-related proteins in brain (Rab) GTPases at the same interface occupied by ARFs and then cleaves and/or degrades 24 distinct members of the Rab GTPases family. The cleavage occurs in the C-terminal tails of Rabs. We determine the crystal structure of MCF as a swapped dimer revealing the open, activated state of MCF and then use structure prediction algorithms to show that structural composition, rather than sequence or localization, determine Rabs selected as MCF proteolytic targets. Once cleaved, Rabs become dispersed in cells to drive organelle damage and cell death to promote pathogenesis of these rapidly fatal infections.
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Affiliation(s)
- Alfa Herrera
- Department of Microbiology-Immunology and Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Megan M. Packer
- Department of Microbiology-Immunology and Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Monica Rosas-Lemus
- Department of Microbiology-Immunology and Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology and Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - John H. Brummel
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- SickKids IBD Centre, The Hospital for Sick Children, Toronto, ON, Canada
| | - Karla J. F. Satchell
- Department of Microbiology-Immunology and Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Center for Structural Biology of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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11
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Venkatesan M, Semper C, Skrivergaard S, Di Leo R, Mesa N, Rasmussen MK, Young JF, Therkildsen M, Stogios PJ, Savchenko A. Recombinant production of growth factors for application in cell culture. iScience 2022; 25:105054. [PMID: 36157583 PMCID: PMC9489951 DOI: 10.1016/j.isci.2022.105054] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 06/07/2022] [Accepted: 08/26/2022] [Indexed: 11/04/2022] Open
Abstract
Culturing eukaryotic cells has widespread applications in research and industry, including the emerging field of cell-cultured meat production colloquially referred to as “cellular agriculture”. These applications are often restricted by the high cost of growth medium necessary for cell growth. Mitogenic protein growth factors (GFs) are essential components of growth medium and account for upwards of 90% of the total costs. Here, we present a set of expression constructs and a simplified protocol for recombinant production of functionally active GFs, including FGF2, IGF1, PDGF-BB, and TGF-β1 in Escherichia coli. Using this E. coli expression system, we produced soluble GF orthologs from species including bovine, chicken, and salmon. Bioactivity analysis revealed orthologs with improved performance compared to commercially available alternatives. We estimated that the production cost of GFs using our methodology will significantly reduce the cost of cell culture medium, facilitating low-cost protocols tailored for cultured meat production and tissue engineering. Developed methodology for low-cost production of soluble, bioactive GFs Purified GFs were active on NIH-3T3 and bovine satellite cells Some GF orthologs outperformed commercially sourced GFs Production of GFs using these methods can foster significant cost savings
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Affiliation(s)
- Meenakshi Venkatesan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada
| | - Cameron Semper
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada
| | | | - Rosa Di Leo
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada
| | - Nathalie Mesa
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada
| | | | | | | | - Peter J Stogios
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada
| | - Alexei Savchenko
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E8, Canada.,Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB T2N 4N1, Canada
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12
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Pincus NB, Rosas-Lemus M, Gatesy SWM, Bertucci HK, Brunzelle JS, Minasov G, Shuvalova LA, Lebrun-Corbin M, Satchell KJF, Ozer EA, Hauser AR, Bachta KER. Functional and Structural Characterization of OXA-935, a Novel OXA-10-Family β-Lactamase from Pseudomonas aeruginosa. Antimicrob Agents Chemother 2022; 66:e0098522. [PMID: 36129295 PMCID: PMC9578422 DOI: 10.1128/aac.00985-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/29/2022] [Indexed: 11/20/2022] Open
Abstract
Resistance to antipseudomonal penicillins and cephalosporins is often driven by the overproduction of the intrinsic β-lactamase AmpC. However, OXA-10-family β-lactamases are a rich source of resistance in Pseudomonas aeruginosa. OXA β-lactamases have a propensity for mutation that leads to extended spectrum cephalosporinase and carbapenemase activity. In this study, we identified isolates from a subclade of the multidrug-resistant (MDR) high risk P. aeruginosa clonal complex CC446 with a resistance to ceftazidime. A genomic analysis revealed that these isolates harbored a plasmid containing a novel allele of blaOXA-10, named blaOXA-935, which was predicted to produce an OXA-10 variant with two amino acid substitutions: an aspartic acid instead of a glycine at position 157 and a serine instead of a phenylalanine at position 153. The G157D mutation, present in OXA-14, is associated with the resistance of P. aeruginosa to ceftazidime. Compared to OXA-14, OXA-935 showed increased catalytic efficiency for ceftazidime. The deletion of blaOXA-935 restored the sensitivity to ceftazidime, and susceptibility profiling of P. aeruginosa laboratory strains expressing blaOXA-935 revealed that OXA-935 conferred ceftazidime resistance. To better understand the impacts of the variant amino acids, we determined the crystal structures of OXA-14 and OXA-935. Compared to OXA-14, the F153S mutation in OXA-935 conferred increased flexibility in the omega (Ω) loop. Amino acid changes that confer extended spectrum cephalosporinase activity to OXA-10-family β-lactamases are concerning, given the rising reliance on novel β-lactam/β-lactamase inhibitor combinations, such as ceftolozane-tazobactam and ceftazidime-avibactam, to treat MDR P. aeruginosa infections.
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Affiliation(s)
- Nathan B. Pincus
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Monica Rosas-Lemus
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Samuel W. M. Gatesy
- Department of Medicine, Division of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Hanna K. Bertucci
- Department of Medicine, Division of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Joseph S. Brunzelle
- Northwestern Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Ludmilla A. Shuvalova
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Marine Lebrun-Corbin
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Karla J. F. Satchell
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Egon A. Ozer
- Department of Medicine, Division of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Pathogen Genomics and Microbial Evolution, Institute for Global Health, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Alan R. Hauser
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Department of Medicine, Division of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Kelly E. R. Bachta
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
- Department of Medicine, Division of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
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13
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Bartelli NL, Passanisi VJ, Michalska K, Song K, Nhan DQ, Zhou H, Cuthbert BJ, Stols LM, Eschenfeldt WH, Wilson NG, Basra JS, Cortes R, Noorsher Z, Gabraiel Y, Poonen-Honig I, Seacord EC, Goulding CW, Low DA, Joachimiak A, Dahlquist FW, Hayes CS. Proteolytic processing induces a conformational switch required for antibacterial toxin delivery. Nat Commun 2022; 13:5078. [PMID: 36038560 PMCID: PMC9424206 DOI: 10.1038/s41467-022-32795-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 08/12/2022] [Indexed: 02/08/2023] Open
Abstract
Many Gram-negative bacteria use CdiA effector proteins to inhibit the growth of neighboring competitors. CdiA transfers its toxic CdiA-CT region into the periplasm of target cells, where it is released through proteolytic cleavage. The N-terminal cytoplasm-entry domain of the CdiA-CT then mediates translocation across the inner membrane to deliver the C-terminal toxin domain into the cytosol. Here, we show that proteolysis not only liberates the CdiA-CT for delivery, but is also required to activate the entry domain for membrane translocation. Translocation function depends on precise cleavage after a conserved VENN peptide sequence, and the processed ∆VENN entry domain exhibits distinct biophysical and thermodynamic properties. By contrast, imprecisely processed CdiA-CT fragments do not undergo this transition and fail to translocate to the cytoplasm. These findings suggest that CdiA-CT processing induces a critical structural switch that converts the entry domain into a membrane-translocation competent conformation.
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Affiliation(s)
- Nicholas L Bartelli
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Victor J Passanisi
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Karolina Michalska
- Midwest Center for Structural Genomics, Argonne National Laboratory, Lemont, IL, USA
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL, USA
| | - Kiho Song
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA
| | - Dinh Q Nhan
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Hongjun Zhou
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Bonnie J Cuthbert
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, USA
| | - Lucy M Stols
- Midwest Center for Structural Genomics, Argonne National Laboratory, Lemont, IL, USA
| | - William H Eschenfeldt
- Midwest Center for Structural Genomics, Argonne National Laboratory, Lemont, IL, USA
| | - Nicholas G Wilson
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Jesse S Basra
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Ricardo Cortes
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Zainab Noorsher
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Youssef Gabraiel
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Isaac Poonen-Honig
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Elizabeth C Seacord
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Celia W Goulding
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, USA
- Pharmaceutical Sciences, University of California, Irvine, CA, USA
| | - David A Low
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Argonne National Laboratory, Lemont, IL, USA
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Frederick W Dahlquist
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Christopher S Hayes
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA.
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA.
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14
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Cherny KE, Balaji A, Mukherjee J, Goo YA, Hauser AR, Ozer E, Satchell KJF, Bachta KER, Kochan TJ, Mitra SD, Kociolek LK. Identification of Clostridium innocuum hypothetical protein that is cross-reactive with C. difficile anti-toxin antibodies. Anaerobe 2022; 75:102555. [PMID: 35367613 PMCID: PMC9197939 DOI: 10.1016/j.anaerobe.2022.102555] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/25/2022] [Accepted: 03/28/2022] [Indexed: 11/01/2022]
Abstract
OBJECTIVES Previously considered solely an opportunistic pathogen, Clostridium innocuum (CI) was recently reported in Taiwan to be an emerging cause of antibiotic-associated diarrhea and clinically indistinguishable from Clostridioides difficile (CD) infection. We previously identified CI culture supernatant being cross-reactive with commercial CD toxin enzyme immunoassays. We aimed to identify and characterize the cross-reacting protein and determine whether it functioned as a human toxin. METHODS We performed western blots using CI culture supernatants and CD anti-toxin antibodies and identified interacting bands. We identified protein(s) using tandem mass spectrometry and evaluated them by cytotoxicity assays. RESULTS CI, but not CD, was isolated from stool of 12 children and adults with diarrhea. Culture supernatant from 6/12 CI isolates, and an ATCC reference strain, tested positive for CD toxins (total 7/13 isolates) by commercial EIA. Using two of these isolates, we identified two ∼40 kDa hypothetical proteins, CI_01447 and CI_01448, and confirmed cross-reactivity with CD anti-toxin antibodies by enzyme immunoassay and Western blot. Whole-genome sequencing confirmed all 13 isolates contained both genes, which were highly conserved. We observed no cytopathic or cytotoxic effects to HeLa cells when treated with these proteins. We identified amino acid sequence similarity to the NlpC/P60 family of proteins. CONCLUSIONS Our findings do not suggest CI proteins CI_01448 and CI_01447, which cross-react with antibodies against CD toxins A and B, are toxic to HeLa cells. Further studies are needed to determine the function of these cross-reacting proteins and the potential virulence factors that could be responsible for CI diarrheal disease.
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Affiliation(s)
- K E Cherny
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA; Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.
| | - A Balaji
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - J Mukherjee
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Y A Goo
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - A R Hauser
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - E Ozer
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - K J F Satchell
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA; Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - K E R Bachta
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - T J Kochan
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - S D Mitra
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - L K Kociolek
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA; Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
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15
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A Genomic Island of Vibrio cholerae Encodes a Three-Component Cytotoxin with Monomer and Protomer Forms Structurally Similar to Alpha-Pore-Forming Toxins. J Bacteriol 2022; 204:e0055521. [PMID: 35435721 DOI: 10.1128/jb.00555-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Alpha-pore-forming toxins (α-PFTs) are secreted by many species of bacteria, including Escherichia coli, Aeromonas hydrophila, and Bacillus thuringiensis, as part of their arsenal of virulence factors, and are often cytotoxic. In particular, for α-PFTs, the membrane-spanning channel they form is composed of hydrophobic α-helices. These toxins oligomerize at the surface of target cells and transition from a soluble to a protomer state in which they expose their hydrophobic regions and insert into the membrane to form a pore. The pores may be composed of homooligomers of one component or heterooligomers with two or three components, resulting in bi- or tripartite toxins. The multicomponent α-PFTs are often expressed from a single operon. Recently, motility-associated killing factor A (MakA), an α-PFT, was discovered in Vibrio cholerae. We report that makA is found on the V. cholerae GI-10 genomic island within an operon containing genes for two other potential α-PFTs, MakB and MakE. We determined the X-ray crystal structures for MakA, MakB, and MakE and demonstrated that all three are structurally related to the α-PFT family in the soluble state, and we modeled their protomer state based on the α-PFT AhlB from A. hydrophila. We found that MakA alone is cytotoxic at micromolar concentrations. However, combining MakA with MakB and MakE is cytotoxic at nanomolar concentrations, with specificity for J774 macrophage cells. Our data suggest that MakA, -B, and -E are α-PFTs that potentially act as a tripartite pore-forming toxin with specificity for phagocytic cells. IMPORTANCE The bacterium Vibrio cholerae causes gastrointestinal, wound, and skin infections. The motility-associated killing factor A (MakA) was recently shown to be cytotoxic against colon, prostate, and other cancer cells. However, at the outset of this study, the capacity of MakA to damage cells in combination with other Mak proteins encoded in the same operon had not been elucidated. We determined the structures of three Mak proteins and established that they are structurally related to the α-PFTs. Compared to MakA alone, the combination of all three toxins was more potent specifically in mouse macrophages. This study highlights the idea that the Mak toxins are selectively cytotoxic and thus may function as a tripartite toxin with cell type specificity.
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16
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Mullowney MW, Maltseva NI, Endres M, Kim Y, Joachimiak A, Crofts TS. Functional and Structural Characterization of Diverse NfsB Chloramphenicol Reductase Enzymes from Human Pathogens. Microbiol Spectr 2022; 10:e0013922. [PMID: 35195438 PMCID: PMC8941942 DOI: 10.1128/spectrum.00139-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/02/2022] [Indexed: 11/20/2022] Open
Abstract
Phylogenetically diverse bacteria can carry out chloramphenicol reduction, but only a single enzyme has been described that efficiently catalyzes this reaction, the NfsB nitroreductase from Haemophilus influenzae strain KW20. Here, we tested the hypothesis that some NfsB homologs function as housekeeping enzymes with the potential to become chloramphenicol resistance enzymes. We found that expression of H. influenzae and Neisseria spp. nfsB genes, but not Pasteurella multocida nfsB, allows Escherichia coli to resist chloramphenicol by nitroreduction. Mass spectrometric analysis confirmed that purified H. influenzae and N. meningitides NfsB enzymes reduce chloramphenicol to amino-chloramphenicol, while kinetics analyses supported the hypothesis that chloramphenicol reduction is a secondary activity. We combined these findings with atomic resolution structures of multiple chloramphenicol-reducing NfsB enzymes to identify potential key substrate-binding pocket residues. Our work expands the chloramphenicol reductase family and provides mechanistic insights into how a housekeeping enzyme might confer antibiotic resistance. IMPORTANCE The question of how new enzyme activities evolve is of great biological interest and, in the context of antibiotic resistance, of great medical importance. Here, we have tested the hypothesis that new antibiotic resistance mechanisms may evolve from promiscuous housekeeping enzymes that have antibiotic modification side activities. Previous work identified a Haemophilus influenzae nitroreductase housekeeping enzyme that has the ability to give Escherichia coli resistance to the antibiotic chloramphenicol by nitroreduction. Herein, we extend this work to enzymes from other Haemophilus and Neisseria strains to discover that expression of chloramphenicol reductases is sufficient to confer chloramphenicol resistance to Es. coli, confirming that chloramphenicol reductase activity is widespread across this nitroreductase family. By solving the high-resolution crystal structures of active chloramphenicol reductases, we identified residues important for this activity. Our work supports the hypothesis that housekeeping proteins possessing multiple activities can evolve into antibiotic resistance enzymes.
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Affiliation(s)
| | - Natalia I. Maltseva
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structure Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
| | - Michael Endres
- Structure Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
| | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structure Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois, USA
- Structure Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Terence S. Crofts
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, USA
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17
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Daneshian L, Renggli I, Hanaway R, Offermann LR, Schlachter CR, Hernandez Arriaza R, Henry S, Prakash R, Wybouw N, Dermauw W, Shimizu LS, Van Leeuwen T, Makris TM, Grbic V, Grbic M, Chruszcz M. Structural and functional characterization of β-cyanoalanine synthase from Tetranychus urticae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 142:103722. [PMID: 35063675 DOI: 10.1016/j.ibmb.2022.103722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 01/12/2022] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Tetranychus urticae is a polyphagous spider mite that can feed on more than 1100 plant species including cyanogenic plants. The herbivore genome contains a horizontally acquired gene tetur10g01570 (TuCAS) that was previously shown to participate in cyanide detoxification. To understand the structure and determine the function of TuCAS in T. urticae, crystal structures of the protein with lysine conjugated pyridoxal phosphate (PLP) were determined. These structures reveal extensive TuCAS homology with the β-substituted alanine synthase family, and they show that this enzyme utilizes a similar chemical mechanism involving a stable α-aminoacrylate intermediate in β-cyanoalanine and cysteine synthesis. We demonstrate that TuCAS is more efficient in the synthesis of β-cyanoalanine, which is a product of the detoxification reaction between cysteine and cyanide, than in the biosynthesis of cysteine. Also, the enzyme carries additional enzymatic activities that were not previously described. We show that TuCAS can detoxify cyanide using O-acetyl-L-serine as a substrate, leading to the direct formation of β-cyanoalanine. Moreover, it catalyzes the reaction between the TuCAS-bound α-aminoacrylate intermediate and aromatic compounds with a thiol group. In addition, we have tested several compounds as TuCAS inhibitors. Overall, this study identifies additional functions for TuCAS and provides new molecular insight into the xenobiotic metabolism of T. urticae.
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Affiliation(s)
- Leily Daneshian
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Isabella Renggli
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Ryan Hanaway
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Lesa R Offermann
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Caleb R Schlachter
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | | | - Shannon Henry
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Rahul Prakash
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Nicky Wybouw
- Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, 9000, Belgium
| | - Wannes Dermauw
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Plant Sciences Unit, Merelbeke, 9820, Belgium; Department of Plants and Crops, Ghent University, Ghent, 9000, Belgium
| | - Linda S Shimizu
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | | | - Thomas M Makris
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA; Department of Molecular and Structural Biochemistry, NC State University, Raleigh, NC, 27607, USA
| | - Vojislava Grbic
- Department of Biology, Western University, London, Ontario, N6A 5B7, Canada
| | - Miodrag Grbic
- Department of Biology, Western University, London, Ontario, N6A 5B7, Canada; University of La Rioja, Logrono, Spain
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA.
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18
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Hodge CD, Rosenberg DJ, Wilamowski M, Joachimiak A, Hura GL, Hammel M. Rigid monoclonal antibodies improve detection of SARS-CoV-2 nucleocapsid protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.01.13.426597. [PMID: 33469584 PMCID: PMC7814821 DOI: 10.1101/2021.01.13.426597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Monoclonal antibodies (mAbs) are the basis of treatments and diagnostics for pathogens and other biological phenomena. We conducted a structural characterization of mAbs against the N-terminal domain of nucleocapsid protein (NP NTD ) from SARS-CoV-2 using small angle X-ray scattering (SAXS). Our solution-based results distinguished the mAbs' flexibility and how this flexibility impacts the assembly of multiple mAbs on an antigen. By pairing two mAbs that bind different epitopes on the NP NTD , we show that flexible mAbs form a closed sandwich-like complex. With rigid mAbs, a juxtaposition of the Fabs is prevented, enforcing a linear arrangement of the mAb pair, which facilitates further mAb polymerization. In a modified sandwich ELISA, we show the rigid mAb-pairings with linear polymerization led to increased NP NTD detection sensitivity. These enhancements can expedite the development of more sensitive and selective antigen-detecting point-of-care lateral flow devices (LFA), key for early diagnosis and epidemiological studies of SARS-CoV-2 and other pathogens.
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Affiliation(s)
- Curtis D Hodge
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Daniel J Rosenberg
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mateusz Wilamowski
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, USA
| | - Greg L Hura
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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19
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Hodge CD, Rosenberg DJ, Grob P, Wilamowski M, Joachimiak A, Hura GL, Hammel M. Rigid monoclonal antibodies improve detection of SARS-CoV-2 nucleocapsid protein. MAbs 2021; 13:1905978. [PMID: 33843452 PMCID: PMC8043170 DOI: 10.1080/19420862.2021.1905978] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/10/2021] [Accepted: 03/16/2021] [Indexed: 12/13/2022] Open
Abstract
Monoclonal antibodies (mAbs) are the basis of treatments and diagnostics for pathogens and other biological phenomena. We conducted a structural characterization of mAbs against the N-terminal domain of nucleocapsid protein (NPNTD) from SARS-CoV-2 using small-angle X-ray scattering and transmission electron microscopy. Our solution-based results distinguished the mAbs' flexibility and how this flexibility affects the assembly of multiple mAbs on an antigen. By pairing two mAbs that bind different epitopes on the NPNTD, we show that flexible mAbs form a closed sandwich-like complex. With rigid mAbs, a juxtaposition of the antigen-binding fragments is prevented, enforcing a linear arrangement of the mAb pair, which facilitates further mAb polymerization. In a modified sandwich enzyme-linked immunosorbent assay, we show that rigid mAb-pairings with linear polymerization led to increased NPNTD detection sensitivity. These enhancements can expedite the development of more sensitive and selective antigen-detecting point-of-care lateral flow devices, which are critical for early diagnosis and epidemiological studies of SARS-CoV-2 and other pathogens.
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Affiliation(s)
- Curtis D. Hodge
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Daniel. J. Rosenberg
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Graduate Group in Biophysics, University of California, Berkeley, CA, USA
| | - Patricia Grob
- Howard Hughes Medical Institute, UC Berkeley, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | - Mateusz Wilamowski
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL, USA
| | - Greg L. Hura
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Chemistry and Biochemistry Department, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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20
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Choolaei Z, Flick R, Khusnutdinova AN, Edwards EA, Yakunin AF. Lignin-oxidizing activity of bacterial laccases characterized using soluble substrates and polymeric lignin. J Biotechnol 2020; 325:128-137. [PMID: 33186661 DOI: 10.1016/j.jbiotec.2020.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 10/21/2020] [Accepted: 11/03/2020] [Indexed: 12/11/2022]
Abstract
Efficient biotransformation of lignin requires the activity of different oxidative enzymes. In this work, 19 bacterial multi-copper oxidases were screened for oxidase activity against 19 soluble substrates and revealed the highest activity in the laccase CotABsu (BSU0630) from Bacillus subtilis. Structure-based site-directed mutagenesis of CotABsu identified four conserved residues (His419, Cys492, His497, and Met502) as critical for activity against 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonate) (ABTS). Greatly reduced oxidase activity was found in the CotABsu mutant proteins E213A, N214A, C229A, N264A, E298A, T415A, R416A, Q468A, and T480A. We also designed a lignin-agarose plate screen for detecting oxidase activity of purified proteins against polymeric lignin, which confirmed the results obtained with ABTS and identified three mutant variants with increased activity toward kraft lignin (E213A, T415A, and T260A). X-ray photoelectron spectroscopy analysis of low sulfonate kraft lignin after incubation with CotABsu revealed a reduction in the content of CC/CC bonds and increase in CO/CO bonds. Product analyses using mass spectrometry, liquid chromatography, and bright-field microscopy revealed an increased polymerization state of reaction products suggesting that formation of radical intermediates was followed by radical coupling. Our results provide further insights into the mechanisms of lignin oxidation by laccases.
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Affiliation(s)
- Zahra Choolaei
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Robert Flick
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Anna N Khusnutdinova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Elizabeth A Edwards
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Alexander F Yakunin
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada; Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Bangor, LL57 2UW, UK.
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21
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Rosas-Lemus M, Minasov G, Shuvalova L, Inniss NL, Kiryukhina O, Brunzelle J, Satchell KJF. High-resolution structures of the SARS-CoV-2 2'- O-methyltransferase reveal strategies for structure-based inhibitor design. Sci Signal 2020; 13:eabe1202. [PMID: 32994211 PMCID: PMC8028745 DOI: 10.1126/scisignal.abe1202] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
There are currently no antiviral therapies specific for SARS-CoV-2, the virus responsible for the global pandemic disease COVID-19. To facilitate structure-based drug design, we conducted an x-ray crystallographic study of the SARS-CoV-2 nsp16-nsp10 2'-O-methyltransferase complex, which methylates Cap-0 viral mRNAs to improve viral protein translation and to avoid host immune detection. We determined the structures for nsp16-nsp10 heterodimers bound to the methyl donor S-adenosylmethionine (SAM), the reaction product S-adenosylhomocysteine (SAH), or the SAH analog sinefungin (SFG). We also solved structures for nsp16-nsp10 in complex with the methylated Cap-0 analog m7GpppA and either SAM or SAH. Comparative analyses between these structures and published structures for nsp16 from other betacoronaviruses revealed flexible loops in open and closed conformations at the m7GpppA-binding pocket. Bound sulfates in several of the structures suggested the location of the ribonucleic acid backbone phosphates in the ribonucleotide-binding groove. Additional nucleotide-binding sites were found on the face of the protein opposite the active site. These various sites and the conserved dimer interface could be exploited for the development of antiviral inhibitors.
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Affiliation(s)
- Monica Rosas-Lemus
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ludmilla Shuvalova
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Nicole L Inniss
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Olga Kiryukhina
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Joseph Brunzelle
- Northwestern Synchrotron Research Center, Life Sciences Collaborative Access Team, Northwestern University, Argonne, IL 60439, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA.
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
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22
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Minasov G, Lam MR, Rosas-Lemus M, Sławek J, Woinska M, Shabalin IG, Shuvalova L, Palsson BØ, Godzik A, Minor W, Satchell KJF. Comparison of metal-bound and unbound structures of aminopeptidase B proteins from Escherichia coli and Yersinia pestis. Protein Sci 2020; 29:1618-1628. [PMID: 32306515 DOI: 10.1002/pro.3876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 04/14/2020] [Accepted: 04/14/2020] [Indexed: 11/06/2022]
Abstract
Protein degradation by aminopeptidases is involved in bacterial responses to stress. Escherichia coli produces two metal-dependent M17 family leucine aminopeptidases (LAPs), aminopeptidase A (PepA) and aminopeptidase B (PepB). Several structures have been solved for PepA as well as other bacterial M17 peptidases. Herein, we report the first structures of a PepB M17 peptidase. The E. coli PepB protein structure was determined at a resolution of 2.05 and 2.6 Å. One structure has both Zn2+ and Mn2+ , while the second structure has two Zn2+ ions bound to the active site. A 2.75 Å apo structure is also reported for PepB from Yersinia pestis. Both proteins form homohexamers, similar to the overall arrangement of PepA and other M17 peptidases. However, the divergent N-terminal domain in PepB is much larger resulting in a tertiary structure that is more expanded. Modeling of a dipeptide substrate into the C-terminal LAP domain reveals contacts that account for PepB to uniquely cleave after aspartate.
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Affiliation(s)
- George Minasov
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Matthew R Lam
- Department of Molecular Biosciences, Weinberg School of Arts and Sciences, Northwestern University, Evanston, Illinois, USA
| | - Monica Rosas-Lemus
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Joanna Sławek
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Magdalena Woinska
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ivan G Shabalin
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ludmilla Shuvalova
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
| | - Bernhard Ø Palsson
- Department of Bioengineering and Pediatrics, University of California, San Diego, California, USA
| | - Adam Godzik
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Biomedical Sciences, University of California, Riverside School of Medicine, Riverside, California, USA
| | - Wladek Minor
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Center for Structural Genomics of Infectious Diseases, Northwestern University, Chicago, Illinois, USA
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23
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Rosas-Lemus M, Minasov G, Shuvalova L, Inniss NL, Kiryukhina O, Wiersum G, Kim Y, Jedrzejczak R, Maltseva NI, Endres M, Jaroszewski L, Godzik A, Joachimiak A, Satchell KJF. The crystal structure of nsp10-nsp16 heterodimer from SARS-CoV-2 in complex with S-adenosylmethionine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.04.17.047498. [PMID: 32511376 PMCID: PMC7263505 DOI: 10.1101/2020.04.17.047498] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
SARS-CoV-2 is a member of the coronaviridae family and is the etiological agent of the respiratory Coronavirus Disease 2019. The virus has spread rapidly around the world resulting in over two million cases and nearly 150,000 deaths as of April 17, 2020. Since no treatments or vaccines are available to treat COVID-19 and SARS-CoV-2, respiratory complications derived from the infections have overwhelmed healthcare systems around the world. This virus is related to SARS-CoV-1, the virus that caused the 2002-2004 outbreak of Severe Acute Respiratory Syndrome. In January 2020, the Center for Structural Genomics of Infectious Diseases implemented a structural genomics pipeline to solve the structures of proteins essential for coronavirus replication-transcription. Here we show the first structure of the SARS-CoV-2 nsp10-nsp16 2'-O-methyltransferase complex with S-adenosylmethionine at a resolution of 1.80 Å. This heterodimer complex is essential for capping viral mRNA transcripts for efficient translation and to evade immune surveillance.
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Affiliation(s)
- Monica Rosas-Lemus
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Ludmilla Shuvalova
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Nicole L. Inniss
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Olga Kiryukhina
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Grant Wiersum
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60667, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Robert Jedrzejczak
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60667, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Natalia I. Maltseva
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60667, USA
| | - Michael Endres
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60667, USA
| | - Lukasz Jaroszewski
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Department of Biomedical Sciences, University of California, Riverside School of Medicine, Riverside, CA, USA
| | - Adam Godzik
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Department of Biomedical Sciences, University of California, Riverside School of Medicine, Riverside, CA, USA
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, IL 60667, USA
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Karla J. F. Satchell
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
- Center for Structural Genomics of Infectious Diseases, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
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24
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Déjean G, Tamura K, Cabrera A, Jain N, Pudlo NA, Pereira G, Viborg AH, Van Petegem F, Martens EC, Brumer H. Synergy between Cell Surface Glycosidases and Glycan-Binding Proteins Dictates the Utilization of Specific Beta(1,3)-Glucans by Human Gut Bacteroides. mBio 2020; 11:e00095-20. [PMID: 32265336 PMCID: PMC7157763 DOI: 10.1128/mbio.00095-20] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/09/2020] [Indexed: 01/06/2023] Open
Abstract
The human gut microbiota (HGM) has far-reaching impacts on human health and nutrition, which are fueled primarily by the metabolism of otherwise indigestible complex carbohydrates commonly known as dietary fiber. However, the molecular basis of the ability of individual taxa of the HGM to address specific dietary glycan structures remains largely unclear. In particular, the utilization of β(1,3)-glucans, which are widespread in the human diet as yeast, seaweed, and plant cell walls, had not previously been resolved. Through a systems-based approach, here we show that the symbiont Bacteroides uniformis deploys a single, exemplar polysaccharide utilization locus (PUL) to access yeast β(1,3)-glucan, brown seaweed β(1,3)-glucan (laminarin), and cereal mixed-linkage β(1,3)/β(1,4)-glucan. Combined biochemical, enzymatic, and structural analysis of PUL-encoded glycoside hydrolases (GHs) and surface glycan-binding proteins (SGBPs) illuminates a concerted molecular system by which B. uniformis recognizes and saccharifies these distinct β-glucans. Strikingly, the functional characterization of homologous β(1,3)-glucan utilization loci (1,3GUL) in other Bacteroides further demonstrated that the ability of individual taxa to utilize β(1,3)-glucan variants and/or β(1,3)/β(1,4)-glucans arises combinatorially from the individual specificities of SGBPs and GHs at the cell surface, which feed corresponding signals to periplasmic hybrid two-component sensors (HTCSs) via TonB-dependent transporters (TBDTs). These data reveal the importance of cooperativity in the adaptive evolution of GH and SGBP cohorts to address individual polysaccharide structures. We anticipate that this fine-grained knowledge of PUL function will inform metabolic network analysis and proactive manipulation of the HGM. Indeed, a survey of 2,441 public human metagenomes revealed the international, yet individual-specific, distribution of each 1,3GUL.IMPORTANCEBacteroidetes are a dominant phylum of the human gut microbiota (HGM) that target otherwise indigestible dietary fiber with an arsenal of polysaccharide utilization loci (PULs), each of which is dedicated to the utilization of a specific complex carbohydrate. Here, we provide novel insight into this paradigm through functional characterization of homologous PULs from three autochthonous Bacteroides species, which target the family of dietary β(1,3)-glucans. Through detailed biochemical and protein structural analysis, we observed an unexpected diversity in the substrate specificity of PUL glycosidases and glycan-binding proteins with regard to β(1,3)-glucan linkage and branching patterns. In combination, these individual enzyme and protein specificities support taxon-specific growth on individual β(1,3)-glucans. This detailed metabolic insight, together with a comprehensive survey of individual 1,3GULs across human populations, further expands the fundamental roadmap of the HGM, with potential application to the future development of microbial intervention therapies.
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Affiliation(s)
- Guillaume Déjean
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kazune Tamura
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Adriana Cabrera
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Namrata Jain
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nicholas A Pudlo
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Gabriel Pereira
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Alexander Holm Viborg
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Eric C Martens
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
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25
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Rosas‐Lemus M, Minasov G, Shuvalova L, Wawrzak Z, Kiryukhina O, Mih N, Jaroszewski L, Palsson B, Godzik A, Satchell KJF. Structure of galactarate dehydratase, a new fold in an enolase involved in bacterial fitness after antibiotic treatment. Protein Sci 2020; 29:711-722. [PMID: 31811683 PMCID: PMC7021002 DOI: 10.1002/pro.3796] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/24/2019] [Accepted: 12/04/2019] [Indexed: 11/06/2022]
Abstract
Galactarate dehydratase (GarD) is the first enzyme in the galactarate/glucarate pathway and catalyzes the dehydration of galactarate to 3-keto-5-dehydroxygalactarate. This protein is known to increase colonization fitness of intestinal pathogens in antibiotic-treated mice and to promote bacterial survival during stress. The galactarate/glucarate pathway is widespread in bacteria, but not in humans, and thus could be a target to develop new inhibitors for use in combination therapy to combat antibiotic resistance. The structure of almost all the enzymes of the galactarate/glucarate pathway were solved previously, except for GarD, for which only the structure of the N-terminal domain was determined previously. Herein, we report the first crystal structure of full-length GarD solved using a seleno-methoionine derivative revealing a new protein fold. The protein consists of three domains, each presenting a novel twist as compared to their distant homologs. GarD in the crystal structure forms dimers and each monomer consists of three domains. The N-terminal domain is comprised of a β-clip fold, connected to the second domain by a long unstructured linker. The second domain serves as a dimerization interface between two monomers. The C-terminal domain forms an unusual variant of a Rossmann fold with a crossover and is built around a seven-stranded parallel β-sheet supported by nine α-helices. A metal binding site in the C-terminal domain is occupied by Ca2+ . The activity of GarD was corroborated by the production of 5-keto-4-deoxy-D-glucarate under reducing conditions and in the presence of iron. Thus, GarD is an unusual enolase with a novel protein fold never previously seen in this class of enzymes.
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Affiliation(s)
- Monica Rosas‐Lemus
- Department of Microbiology‐ImmunologyNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
| | - George Minasov
- Department of Microbiology‐ImmunologyNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
| | - Ludmilla Shuvalova
- Department of Microbiology‐ImmunologyNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
| | - Zdzislaw Wawrzak
- Northwestern Synchrotron Research Center–LS‐CATNorthwestern UniversityArgonneIllinois
| | - Olga Kiryukhina
- Department of Microbiology‐ImmunologyNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
| | - Nathan Mih
- Department of BioengineeringUniversity of California San DiegoLa JollaCalifornia
| | - Lukasz Jaroszewski
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Department of Biomedical SciencesUniversity of California at RiversideRiversideCalifornia
| | - Bernhard Palsson
- Department of BioengineeringUniversity of California San DiegoLa JollaCalifornia
- Systems Biology Center for Antibiotic ResistanceUniversity of California San DiegoLa JollaCalifornia
| | - Adam Godzik
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Department of Biomedical SciencesUniversity of California at RiversideRiversideCalifornia
| | - Karla J. F. Satchell
- Department of Microbiology‐ImmunologyNorthwestern University, Feinberg School of MedicineChicagoIllinois
- Center for Structural Genomics of Infectious DiseasesNorthwestern University, Feinberg School of MedicineChicagoIllinois
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26
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Alcala A, Ramirez G, Solis A, Kim Y, Tan K, Luna O, Nguyen K, Vazquez D, Ward M, Zhou M, Mulligan R, Maltseva N, Kuhn ML. Structural and functional characterization of three Type B and C chloramphenicol acetyltransferases from Vibrio species. Protein Sci 2019; 29:695-710. [PMID: 31762145 DOI: 10.1002/pro.3793] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/22/2019] [Accepted: 11/22/2019] [Indexed: 12/19/2022]
Abstract
Chloramphenicol acetyltransferases (CATs) were among the first antibiotic resistance enzymes identified and have long been studied as model enzymes for examining plasmid-mediated antibiotic resistance. These enzymes acetylate the antibiotic chloramphenicol, which renders it incapable of inhibiting bacterial protein synthesis. CATs can be classified into different types: Type A CATs are known to be important for antibiotic resistance to chloramphenicol and fusidic acid. Type B CATs are often called xenobiotic acetyltransferases and adopt a similar structural fold to streptogramin acetyltransferases, which are known to be critical for streptogramin antibiotic resistance. Type C CATs have recently been identified and can also acetylate chloramphenicol, but their roles in antibiotic resistance are largely unknown. Here, we structurally and kinetically characterized three Vibrio CAT proteins from a nonpathogenic species (Aliivibrio fisheri) and two important human pathogens (Vibrio cholerae and Vibrio vulnificus). We found all three proteins, including one in a superintegron (V. cholerae), acetylated chloramphenicol, but did not acetylate aminoglycosides or dalfopristin. We also determined the 3D crystal structures of these CATs alone and in complex with crystal violet and taurocholate. These compounds are known inhibitors of Type A CATs, but have not been explored in Type B and Type C CATs. Based on sequence, structure, and kinetic analysis, we concluded that the V. cholerae and V. vulnificus CATs belong to the Type B class and the A. fisheri CAT belongs to the Type C class. Ultimately, our results provide a framework for studying the evolution of antibiotic resistance gene acquisition and chloramphenicol acetylation in Vibrio and other species.
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Affiliation(s)
- Ashley Alcala
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Guadalupe Ramirez
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Allan Solis
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois.,Structural Biology Center X-ray Science Division Argonne National Laboratory, Argonne, Illinois
| | - Kemin Tan
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois.,Structural Biology Center X-ray Science Division Argonne National Laboratory, Argonne, Illinois
| | - Oscar Luna
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Karen Nguyen
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Daniel Vazquez
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Michael Ward
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
| | - Min Zhou
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois.,Structural Biology Center X-ray Science Division Argonne National Laboratory, Argonne, Illinois
| | - Rory Mulligan
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois.,Structural Biology Center X-ray Science Division Argonne National Laboratory, Argonne, Illinois
| | - Natalia Maltseva
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois.,Structural Biology Center X-ray Science Division Argonne National Laboratory, Argonne, Illinois
| | - Misty L Kuhn
- San Francisco State University, Department of Chemistry and Biochemistry, San Francisco, California
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27
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Ritzert JT, Minasov G, Embry R, Schipma MJ, Satchell KJF. The Cyclic AMP Receptor Protein Regulates Quorum Sensing and Global Gene Expression in Yersinia pestis during Planktonic Growth and Growth in Biofilms. mBio 2019; 10:e02613-19. [PMID: 31744922 PMCID: PMC6867900 DOI: 10.1128/mbio.02613-19] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 10/08/2019] [Indexed: 12/16/2022] Open
Abstract
Cyclic AMP (cAMP) receptor protein (Crp) is an important transcriptional regulator of Yersinia pestis Expression of crp increases during pneumonic plague as the pathogen depletes glucose and forms large biofilms within lungs. To better understand control of Y. pestis Crp, we determined a 1.8-Å crystal structure of the protein-cAMP complex. We found that compared to Escherichia coli Crp, C helix amino acid substitutions in Y. pestis Crp did not impact the cAMP dependency of Crp to bind DNA promoters. To investigate Y. pestis Crp-regulated genes during plague pneumonia, we performed RNA sequencing on both wild-type and Δcrp mutant bacteria growing in planktonic and biofilm states in minimal media with glucose or glycerol. Y. pestis Crp was found to dramatically alter expression of hundreds of genes in a manner dependent upon carbon source and growth state. Gel shift assays confirmed direct regulation of the malT and ptsG promoters, and Crp was then linked to Y. pestis growth on maltose as a sole carbon source. Iron regulation genes ybtA and fyuA were found to be indirectly regulated by Crp. A new connection between carbon source and quorum sensing was revealed as Crp was found to regulate production of acyl-homoserine lactones (AHLs) through direct and indirect regulation of genes for AHL synthetases and receptors. AHLs were subsequently identified in the lungs of Y. pestis-infected mice when crp expression was highest in Y. pestis biofilms. Thus, in addition to the well-studied pla gene, other Crp-regulated genes likely have important functions during plague infection.IMPORTANCE Bacterial pathogens have evolved extensive signaling pathways to translate environmental signals into changes in gene expression. While Crp has long been appreciated for its role in regulating metabolism of carbon sources in many bacterial species, transcriptional profiling has revealed that this protein regulates many other aspects of bacterial physiology. The plague pathogen Y. pestis requires this global regulator to survive in blood, skin, and lungs. During disease progression, this organism adapts to changes within these niches. In addition to regulating genes for metabolism of nonglucose sugars, we found that Crp regulates genes for virulence, metal acquisition, and quorum sensing by direct or indirect mechanisms. Thus, this single transcriptional regulator, which responds to changes in available carbon sources, can regulate multiple critical behaviors for causing disease.
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Affiliation(s)
- Jeremy T Ritzert
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - George Minasov
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Ryan Embry
- Center for Genetic Medicine, Northwestern University, Chicago, Illinois, USA
| | - Matthew J Schipma
- Center for Genetic Medicine, Northwestern University, Chicago, Illinois, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
- Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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28
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Déjean G, Tauzin AS, Bennett SW, Creagh AL, Brumer H. Adaptation of Syntenic Xyloglucan Utilization Loci of Human Gut Bacteroidetes to Polysaccharide Side Chain Diversity. Appl Environ Microbiol 2019; 85:e01491-19. [PMID: 31420336 PMCID: PMC6805095 DOI: 10.1128/aem.01491-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 08/08/2019] [Indexed: 12/16/2022] Open
Abstract
Genome sequencing has revealed substantial variation in the predicted abilities of individual species within animal gut microbiota to metabolize the complex carbohydrates comprising dietary fiber. At the same time, a currently limited body of functional studies precludes a richer understanding of how dietary glycan structures affect the gut microbiota composition and community dynamics. Here, using biochemical and biophysical techniques, we identified and characterized differences among recombinant proteins from syntenic xyloglucan utilization loci (XyGUL) of three Bacteroides and one Dysgonomonas species from the human gut, which drive substrate specificity and access to distinct polysaccharide side chains. Enzymology of four syntenic glycoside hydrolase family 5 subfamily 4 (GH5_4) endo-xyloglucanases revealed surprising differences in xyloglucan (XyG) backbone cleavage specificity, including the ability of some homologs to hydrolyze congested branched positions. Further, differences in the complement of GH43 alpha-l-arabinofuranosidases and GH95 alpha-l-fucosidases among syntenic XyGUL confer distinct abilities to fully saccharify plant species-specific arabinogalactoxyloglucan and/or fucogalactoxyloglucan. Finally, characterization of highly sequence-divergent cell surface glycan-binding proteins (SGBPs) across syntenic XyGUL revealed a novel group of XyG oligosaccharide-specific SGBPs encoded within select BacteroidesIMPORTANCE The catabolism of complex carbohydrates that otherwise escape the endogenous digestive enzymes of humans and other animals drives the composition and function of the gut microbiota. Thus, detailed molecular characterization of dietary glycan utilization systems is essential both to understand the ecology of these complex communities and to manipulate their compositions, e.g., to benefit human health. Our research reveals new insight into how ubiquitous members of the human gut microbiota have evolved a set of microheterogeneous gene clusters to efficiently respond to the structural variations of plant xyloglucans. The data here will enable refined functional prediction of xyloglucan utilization among diverse environmental taxa in animal guts and beyond.
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Affiliation(s)
- Guillaume Déjean
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alexandra S Tauzin
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stuart W Bennett
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - A Louise Creagh
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
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29
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Convergent Evolution of the Barnase/EndoU/Colicin/RelE (BECR) Fold in Antibacterial tRNase Toxins. Structure 2019; 27:1660-1674.e5. [PMID: 31515004 DOI: 10.1016/j.str.2019.08.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 08/03/2019] [Accepted: 08/20/2019] [Indexed: 11/20/2022]
Abstract
Contact-dependent growth inhibition (CDI) is a form of interbacterial competition mediated by CdiB-CdiA two-partner secretion systems. CdiA effector proteins carry polymorphic C-terminal toxin domains (CdiA-CT), which are neutralized by specific CdiI immunity proteins to prevent self-inhibition. Here, we present the crystal structures of CdiA-CT⋅CdiI complexes from Klebsiella pneumoniae 342 and Escherichia coli 3006. The toxins adopt related folds that resemble the ribonuclease domain of colicin D, and both are isoacceptor-specific tRNases that cleave the acceptor stem of deacylated tRNAGAUIle. Although the toxins are similar in structure and substrate specificity, CdiA-CTKp342 activity requires translation factors EF-Tu and EF-Ts, whereas CdiA-CTEC3006 is intrinsically active. Furthermore, the corresponding immunity proteins are unrelated in sequence and structure. CdiIKp342 forms a dimeric β sandwich, whereas CdiIEC3006 is an α-solenoid monomer. Given that toxin-immunity genes co-evolve as linked pairs, these observations suggest that the similarities in toxin structure and activity reflect functional convergence.
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30
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Schlachter CR, Daneshian L, Amaya J, Klapper V, Wybouw N, Borowski T, Van Leeuwen T, Grbic V, Grbic M, Makris TM, Chruszcz M. Structural and functional characterization of an intradiol ring-cleavage dioxygenase from the polyphagous spider mite herbivore Tetranychus urticae Koch. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 107:19-30. [PMID: 30529144 PMCID: PMC6768081 DOI: 10.1016/j.ibmb.2018.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/20/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
Genome analyses of the polyphagous spider mite herbivore Tetranychus urticae (two-spotted spider mite) revealed the presence of a set of 17 genes that code for secreted proteins belonging to the "intradiol dioxygenase-like" subgroup. Phylogenetic analyses indicate that this novel enzyme family has been acquired by horizontal gene transfer. In order to better understand the role of these proteins in T. urticae, we have structurally and functionally characterized one paralog (tetur07g02040). It was demonstrated that this protein is indeed an intradiol ring-cleavage dioxygenase, as the enzyme is able to cleave catechol between two hydroxyl-groups using atmospheric dioxygen. The enzyme was characterized functionally and structurally. The active site of the T. urticae enzyme contains an Fe3+ cofactor that is coordinated by two histidine and two tyrosine residues, an arrangement that is similar to those observed in bacterial homologs. However, the active site is significantly more solvent exposed than in bacterial proteins. Moreover, the mite enzyme is monomeric, while almost all structurally characterized bacterial homologs form oligomeric assemblies. Tetur07g02040 is not only the first spider mite dioxygenase that has been characterized at the molecular level, but is also the first structurally characterized intradiol ring-cleavage dioxygenase originating from a eukaryote.
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Affiliation(s)
- Caleb R Schlachter
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Leily Daneshian
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Jose Amaya
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Vincent Klapper
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Nicky Wybouw
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, the Netherlands; Department of Plants and Crops, Ghent University, Ghent, B-9000, Belgium
| | - Tomasz Borowski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, 30-239, Krakow, Poland
| | - Thomas Van Leeuwen
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, the Netherlands; Department of Plants and Crops, Ghent University, Ghent, B-9000, Belgium
| | - Vojislava Grbic
- Department of Biology, Western University, London, Ontario, N6A 5B7, Canada; University of La Rioja, Logrono, Spain
| | - Miodrag Grbic
- Department of Biology, Western University, London, Ontario, N6A 5B7, Canada; University of La Rioja, Logrono, Spain
| | - Thomas M Makris
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA.
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31
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Hu LI, Filippova EV, Dang J, Pshenychnyi S, Ruan J, Kiryukhina O, Anderson WF, Kuhn ML, Wolfe AJ. The spermidine acetyltransferase SpeG regulates transcription of the small RNA rprA. PLoS One 2018; 13:e0207563. [PMID: 30562360 PMCID: PMC6298664 DOI: 10.1371/journal.pone.0207563] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 11/23/2018] [Indexed: 01/02/2023] Open
Abstract
Spermidine N-acetyltransferase (SpeG) acetylates and thus neutralizes toxic polyamines. Studies indicate that SpeG plays an important role in virulence and pathogenicity of many bacteria, which have evolved SpeG-dependent strategies to control polyamine concentrations and survive in their hosts. In Escherichia coli, the two-component response regulator RcsB is reported to be subject to Nε-acetylation on several lysine residues, resulting in reduced DNA binding affinity and reduced transcription of the small RNA rprA; however, the physiological acetylation mechanism responsible for this behavior has not been fully determined. Here, we performed an acetyltransferase screen and found that SpeG inhibits rprA promoter activity in an acetylation-independent manner. Surface plasmon resonance analysis revealed that SpeG can physically interact with the DNA-binding carboxyl domain of RcsB. We hypothesize that SpeG interacts with the DNA-binding domain of RcsB and that this interaction might be responsible for SpeG-dependent inhibition of RcsB-dependent rprA transcription. This work provides a model for SpeG as a modulator of E. coli transcription through its ability to interact with the transcription factor RcsB. This is the first study to provide evidence that an enzyme involved in polyamine metabolism can influence the function of the global regulator RcsB, which integrates information concerning envelope stresses and central metabolic status to regulate diverse behaviors.
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Affiliation(s)
- Linda I. Hu
- Department of Microbiology and Immunology, Loyola University Chicago, Health Sciences Division, Stritch School of Medicine, Maywood, IL, United States of America
| | - Ekaterina V. Filippova
- Center for Structural Genomics of Infectious Diseases, Northwestern University Feinberg School of Medicine, Department of Biochemistry and Molecular Genetics, Chicago, IL, United States of America
| | - Joseph Dang
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States of America
| | - Sergii Pshenychnyi
- Recombinant Protein Production Core at Chemistry of Life Processes Institute, Northwestern University, Chicago, IL, United States of America
| | - Jiapeng Ruan
- Center for Structural Genomics of Infectious Diseases, Northwestern University Feinberg School of Medicine, Department of Biochemistry and Molecular Genetics, Chicago, IL, United States of America
| | - Olga Kiryukhina
- Center for Structural Genomics of Infectious Diseases, Northwestern University Feinberg School of Medicine, Department of Biochemistry and Molecular Genetics, Chicago, IL, United States of America
| | - Wayne F. Anderson
- Center for Structural Genomics of Infectious Diseases, Northwestern University Feinberg School of Medicine, Department of Biochemistry and Molecular Genetics, Chicago, IL, United States of America
| | - Misty L. Kuhn
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States of America
| | - Alan J. Wolfe
- Department of Microbiology and Immunology, Loyola University Chicago, Health Sciences Division, Stritch School of Medicine, Maywood, IL, United States of America
- * E-mail:
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32
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Michalska K, Quan Nhan D, Willett JLE, Stols LM, Eschenfeldt WH, Jones AM, Nguyen JY, Koskiniemi S, Low DA, Goulding CW, Joachimiak A, Hayes CS. Functional plasticity of antibacterial EndoU toxins. Mol Microbiol 2018; 109:509-527. [PMID: 29923643 PMCID: PMC6173971 DOI: 10.1111/mmi.14007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2018] [Indexed: 01/05/2023]
Abstract
Bacteria use several different secretion systems to deliver toxic EndoU ribonucleases into neighboring cells. Here, we present the first structure of a prokaryotic EndoU toxin in complex with its cognate immunity protein. The contact-dependent growth inhibition toxin CdiA-CTSTECO31 from Escherichia coli STEC_O31 adopts the eukaryotic EndoU fold and shares greatest structural homology with the nuclease domain of coronavirus Nsp15. The toxin contains a canonical His-His-Lys catalytic triad in the same arrangement as eukaryotic EndoU domains, but lacks the uridylate-specific ribonuclease activity that characterizes the superfamily. Comparative sequence analysis indicates that bacterial EndoU domains segregate into at least three major clades based on structural variations in the N-terminal subdomain. Representative EndoU nucleases from clades I and II degrade tRNA molecules with little specificity. In contrast, CdiA-CTSTECO31 and other clade III toxins are specific anticodon nucleases that cleave tRNAGlu between nucleotides C37 and m2 A38. These findings suggest that the EndoU fold is a versatile scaffold for the evolution of novel substrate specificities. Such functional plasticity may account for the widespread use of EndoU effectors by diverse inter-bacterial toxin delivery systems.
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Affiliation(s)
- Karolina Michalska
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL, USA.,Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL, USA
| | - Dinh Quan Nhan
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Julia L E Willett
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Lucy M Stols
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL, USA
| | - William H Eschenfeldt
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL, USA
| | - Allison M Jones
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Josephine Y Nguyen
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Sanna Koskiniemi
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - David A Low
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA.,Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA
| | - Celia W Goulding
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, USA.,Pharmaceutical Sciences, University of California, Irvine, CA, USA
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL, USA.,Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL, USA.,Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Christopher S Hayes
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA.,Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA, USA
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33
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Michalska K, Gucinski GC, Garza-Sánchez F, Johnson PM, Stols LM, Eschenfeldt WH, Babnigg G, Low DA, Goulding CW, Joachimiak A, Hayes CS. Structure of a novel antibacterial toxin that exploits elongation factor Tu to cleave specific transfer RNAs. Nucleic Acids Res 2017; 45:10306-10320. [PMID: 28973472 PMCID: PMC5737660 DOI: 10.1093/nar/gkx700] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 07/29/2017] [Indexed: 12/23/2022] Open
Abstract
Contact-dependent growth inhibition (CDI) is a mechanism of inter-cellular competition in which Gram-negative bacteria exchange polymorphic toxins using type V secretion systems. Here, we present structures of the CDI toxin from Escherichia coli NC101 in ternary complex with its cognate immunity protein and elongation factor Tu (EF-Tu). The toxin binds exclusively to domain 2 of EF-Tu, partially overlapping the site that interacts with the 3'-end of aminoacyl-tRNA (aa-tRNA). The toxin exerts a unique ribonuclease activity that cleaves the single-stranded 3'-end from tRNAs that contain guanine discriminator nucleotides. EF-Tu is required to support this tRNase activity in vitro, suggesting the toxin specifically cleaves substrate in the context of GTP·EF-Tu·aa-tRNA complexes. However, superimposition of the toxin domain onto previously solved GTP·EF-Tu·aa-tRNA structures reveals potential steric clashes with both aa-tRNA and the switch I region of EF-Tu. Further, the toxin induces conformational changes in EF-Tu, displacing a β-hairpin loop that forms a critical salt-bridge contact with the 3'-terminal adenylate of aa-tRNA. Together, these observations suggest that the toxin remodels GTP·EF-Tu·aa-tRNA complexes to free the 3'-end of aa-tRNA for entry into the nuclease active site.
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Affiliation(s)
- Karolina Michalska
- Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA.,Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Grant C Gucinski
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106-9625, USA
| | - Fernando Garza-Sánchez
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106-9625, USA
| | - Parker M Johnson
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - Lucy M Stols
- Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - William H Eschenfeldt
- Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Gyorgy Babnigg
- Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - David A Low
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106-9625, USA.,Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106-9625, USA
| | - Celia W Goulding
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA.,Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA.,Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA.,Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Christopher S Hayes
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106-9625, USA.,Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106-9625, USA
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Xu Z, Stogios PJ, Quaile AT, Forsberg KJ, Patel S, Skarina T, Houliston S, Arrowsmith C, Dantas G, Savchenko A. Structural and Functional Survey of Environmental Aminoglycoside Acetyltransferases Reveals Functionality of Resistance Enzymes. ACS Infect Dis 2017; 3:653-665. [PMID: 28756664 DOI: 10.1021/acsinfecdis.7b00068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Aminoglycoside N-acetyltransferases (AACs) confer resistance against the clinical use of aminoglycoside antibiotics. The origin of AACs can be traced to environmental microbial species representing a vast reservoir for new and emerging resistance enzymes, which are currently undercharacterized. Here, we performed detailed structural characterization and functional analyses of four metagenomic AAC (meta-AACs) enzymes recently identified in a survey of agricultural and grassland soil microbiomes ( Forsberg et al. Nature 2014 , 509 , 612 ). These enzymes are new members of the Gcn5-Related-N-Acetyltransferase superfamily and confer resistance to the aminoglycosides gentamicin C, sisomicin, and tobramycin. Moreover, the meta-AAC0020 enzyme demonstrated activity comparable with an AAC(3)-I enzyme that serves as a model AAC enzyme identified in a clinical bacterial isolate. The crystal structure of meta-AAC0020 in complex with sisomicin confirmed an unexpected AAC(6') regiospecificity of this enzyme and revealed a drug binding mechanism distinct from previously characterized AAC(6') enzymes. Together, our data highlights the presence of highly active antibiotic-modifying enzymes in the environmental microbiome and reveals unexpected diversity in substrate specificity. These observations of additional AAC enzymes must be considered in the search for novel aminoglycosides less prone to resistance.
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Affiliation(s)
- Zhiyu Xu
- Department of Chemical
Engineering and Applied Chemistry, University of Toronto, 200 College Street, Room 333, Toronto, Ontario M5S 3E5, Canada
| | - Peter J. Stogios
- Department of Chemical
Engineering and Applied Chemistry, University of Toronto, 200 College Street, Room 333, Toronto, Ontario M5S 3E5, Canada
- Center for Structural Genomics of Infectious Diseases (CSGID), Health Research Innovation
Center, 3280 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Andrew T. Quaile
- Department of Chemical
Engineering and Applied Chemistry, University of Toronto, 200 College Street, Room 333, Toronto, Ontario M5S 3E5, Canada
| | - Kevin J. Forsberg
- Center for Genome Sciences & Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Room 5314, St. Louis, Missouri 63110, United States
| | - Sanket Patel
- Center for Genome Sciences & Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Room 5314, St. Louis, Missouri 63110, United States
- Department of Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, United States
| | - Tatiana Skarina
- Department of Chemical
Engineering and Applied Chemistry, University of Toronto, 200 College Street, Room 333, Toronto, Ontario M5S 3E5, Canada
- Center for Structural Genomics of Infectious Diseases (CSGID), Health Research Innovation
Center, 3280 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Scott Houliston
- Department
of Medical Biophysics, University of Toronto, 101 College Street, Room 4-601, Toronto, Ontario M5G 1L7, Canada
| | - Cheryl Arrowsmith
- Department
of Medical Biophysics, University of Toronto, 101 College Street, Room 4-601, Toronto, Ontario M5G 1L7, Canada
| | - Gautam Dantas
- Center for Genome Sciences & Systems Biology, Washington University School of Medicine, 4515 McKinley Avenue, Room 5314, St. Louis, Missouri 63110, United States
- Department of Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, United States
- Department
of Biomedical Engineering, Washington University in St. Louis, 1 Brookings
Drive, St. Louis, Missouri 63130-6100, United States
- Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, Missouri 63110, United States
| | - Alexei Savchenko
- Department of Chemical
Engineering and Applied Chemistry, University of Toronto, 200 College Street, Room 333, Toronto, Ontario M5S 3E5, Canada
- Center for Structural Genomics of Infectious Diseases (CSGID), Health Research Innovation
Center, 3280 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
- Department of Microbiology, Immunology and
Infectious Diseases, University of Calgary, 2C66 Health Research Innovation Center, 3280 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
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35
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Forlani G, Nocek B, Chakravarthy S, Joachimiak A. Functional Characterization of Four Putative δ 1-Pyrroline-5-Carboxylate Reductases from Bacillus subtilis. Front Microbiol 2017; 8:1442. [PMID: 28824574 PMCID: PMC5539093 DOI: 10.3389/fmicb.2017.01442] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/17/2017] [Indexed: 11/21/2022] Open
Abstract
In most living organisms, the amino acid proline is synthesized starting from both glutamate and ornithine. In prokaryotes, in the absence of an ornithine cyclodeaminase that has been identified to date only in a small number of soil and plant bacteria, these pathways share the last step, the reduction of δ1-pyrroline-5-carboxylate (P5C) catalyzed by P5C reductase (EC 1.5.1.2). In several species, multiple forms of P5C reductase have been reported, possibly reflecting the dual function of proline. Aside from its common role as a building block of proteins, proline is indeed also involved in the cellular response to osmotic and oxidative stress conditions. Genome analysis of Bacillus subtilis identifies the presence of four genes (ProH, ProI, ProG, and ComER) that, based on bioinformatic and phylogenic studies, were defined as respectively coding a putative P5C reductase. Here we describe the cloning, heterologous expression, functional analysis and small-angle X-ray scattering studies of the four affinity-purified proteins. Results showed that two of them, namely ProI and ComER, lost their catalytic efficiency or underwent subfunctionalization. In the case of ComER, this could be likely explained by the loss of the ability to form a dimer, which has been previously shown to be an essential structural feature of the catalytically active P5C reductase. The properties of the two active enzymes are consistent with a constitutive role for ProG, and suggest that ProH expression may be beneficial to satisfy an increased need for proline.
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Affiliation(s)
- Giuseppe Forlani
- Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
| | - Boguslaw Nocek
- Center for Structural Genomics of Infectious Diseases, University of ChicagoChicago, IL, United States
| | - Srinivas Chakravarthy
- Argonne National Laboratory, BioCAT, Center for Synchrotron Radiation Research and InstrumentationArgonne, IL, United States
- Department of Biological and Chemical Sciences, Illinois Institute of TechnologyChicago, IL, United States
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, University of ChicagoChicago, IL, United States
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36
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Schlachter CR, Klapper V, Wybouw N, Radford T, Van Leeuwen T, Grbic M, Chruszcz M. Structural Characterization of a Eukaryotic Cyanase from Tetranychus urticae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:5453-5462. [PMID: 28613863 DOI: 10.1021/acs.jafc.7b01333] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The two-spotted spider mite Tetranychus urticae is a polyphagous agricultural pest and poses a high risk to global crop production as it is rapidly developing pesticide resistance. Genomic and transcriptomic analysis has revealed the presence of a remarkable cyanase gene in T. urticae and related mite species within the Acariformes lineage. Cyanase catalyzes the detoxification of cyanate and is potentially an attractive protein target for the development of new acaricides. Phylogenetic analysis indicates that within the Acariformes, the cyanase gene originates from a single horizontal gene transfer event, which precedes subsequent speciation. Our structural studies presented here compare and contrast prokaryotic cyanases to T. urticae cyanase, which all form homodecamers and have conserved active site residues, but display different surface areas between homodimers in the overall decameric structure.
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Affiliation(s)
- Caleb R Schlachter
- Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States
| | - Vincent Klapper
- Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States
| | - Nicky Wybouw
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Taylor Radford
- Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States
| | - Thomas Van Leeuwen
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands
- Department of Crop Protection, Ghent University , Ghent B-9000, Belgium
| | - Miodrag Grbic
- Department of Biology, Western University , London, Ontario N6A 5B7, Canada
- University of La Rioja , Logrono 26006, Spain
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States
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37
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Biancucci M, Dolores JS, Wong J, Grimshaw S, Anderson WF, Satchell KJF, Kwon K. New ligation independent cloning vectors for expression of recombinant proteins with a self-cleaving CPD/6xHis-tag. BMC Biotechnol 2017; 17:1. [PMID: 28056928 PMCID: PMC5216533 DOI: 10.1186/s12896-016-0323-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/09/2016] [Indexed: 12/30/2022] Open
Abstract
Background Recombinant protein purification is a crucial step for biochemistry and structural biology fields. Rapid robust purification methods utilize various peptide or protein tags fused to the target protein for affinity purification using corresponding matrices and to enhance solubility. However, affinity/solubility-tags often need to be removed in order to conduct functional and structural studies, adding complexities to purification protocols. Results In this work, the Vibrio cholerae MARTX toxin Cysteine Protease Domain (CPD) was inserted in a ligation-independent cloning (LIC) vector to create a C-terminal 6xHis-tagged inducible autoprocessing enzyme tag, called “the CPD-tag”. The pCPD and alternative pCPD/ccdB cloning vectors allow for easy insertion of DNA and expression of the target protein fused to the CPD-tag, which is removed at the end of the purification step by addition of the inexpensive small molecule inositol hexakisphosphate to induce CPD autoprocessing. This process is demonstrated using a small bacterial membrane localization domain and for high yield purification of the eukaryotic small GTPase KRas. Subsequently, pCPD was tested with 40 proteins or sub-domains selected from a high throughput crystallization pipeline. Conclusion pCPD vectors are easily used LIC compatible vectors for expression of recombinant proteins with a C-terminal CPD/6xHis-tag. Although intended only as a strategy for rapid tag removal, this pilot study revealed the CPD-tag may also increase expression and solubility of some recombinant proteins. Electronic supplementary material The online version of this article (doi:10.1186/s12896-016-0323-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marco Biancucci
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward 6-205, Chicago, IL, 60611, USA
| | - Jazel S Dolores
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward 6-205, Chicago, IL, 60611, USA.,Present address: Northwestern Memorial Hospital, Chicago, IL, USA
| | - Jennifer Wong
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward 6-205, Chicago, IL, 60611, USA.,Present address: Indiana University, Bloomington, IN, USA
| | - Sarah Grimshaw
- Infectious Diseases Group, J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD, 20850, USA.,Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Wayne F Anderson
- Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.,Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Karla J F Satchell
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, 303 E. Chicago Avenue, Ward 6-205, Chicago, IL, 60611, USA. .,Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
| | - Keehwan Kwon
- Infectious Diseases Group, J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD, 20850, USA. .,Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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38
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Structure to function of an α-glucan metabolic pathway that promotes Listeria monocytogenes pathogenesis. Nat Microbiol 2016; 2:16202. [PMID: 27819654 DOI: 10.1038/nmicrobiol.2016.202] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 09/12/2016] [Indexed: 11/08/2022]
Abstract
Here we employ a 'systems structural biology' approach to functionally characterize an unconventional α-glucan metabolic pathway from the food-borne pathogen Listeria monocytogenes (Lm). Crystal structure determination coupled with basic biochemical and biophysical assays allowed for the identification of anabolic, transport, catabolic and regulatory portions of the cycloalternan pathway. These findings provide numerous insights into cycloalternan pathway function and reveal the mechanism of repressor, open reading frame, kinase (ROK) transcription regulators. Moreover, by developing a structural overview we were able to anticipate the cycloalternan pathway's role in the metabolism of partially hydrolysed starch derivatives and demonstrate its involvement in Lm pathogenesis. These findings suggest that the cycloalternan pathway plays a role in interspecies resource competition-potentially within the host gastrointestinal tract-and establish the methodological framework for characterizing bacterial systems of unknown function.
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39
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Cao H, Tan K, Wang F, Bigelow L, Yennamalli RM, Jedrzejczak R, Babnigg G, Bingman CA, Joachimiak A, Kharel MK, Singh S, Thorson JS, Phillips GN. Structural dynamics of a methionine γ-lyase for calicheamicin biosynthesis: Rotation of the conserved tyrosine stacking with pyridoxal phosphate. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2016; 3:034702. [PMID: 27191010 PMCID: PMC4851618 DOI: 10.1063/1.4948539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 04/21/2016] [Indexed: 06/05/2023]
Abstract
CalE6 from Micromonospora echinospora is a (pyridoxal 5' phosphate) PLP-dependent methionine γ-lyase involved in the biosynthesis of calicheamicins. We report the crystal structure of a CalE6 2-(N-morpholino)ethanesulfonic acid complex showing ligand-induced rotation of Tyr100, which stacks with PLP, resembling the corresponding tyrosine rotation of true catalytic intermediates of CalE6 homologs. Elastic network modeling and crystallographic ensemble refinement reveal mobility of the N-terminal loop, which involves both tetrameric assembly and PLP binding. Modeling and comparative structural analysis of PLP-dependent enzymes involved in Cys/Met metabolism shine light on the functional implications of the intrinsic dynamic properties of CalE6 in catalysis and holoenzyme maturation.
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Affiliation(s)
- Hongnan Cao
- Biosciences at Rice, Rice University , 6100 Main St., Houston, Texas 77005, USA
| | - Kemin Tan
- Biosciences Division, Midwest Center for Structural Genomics, Argonne National Laboratory , Bldg. 446/Rm. A104, 970 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Fengbin Wang
- Biosciences at Rice, Rice University , 6100 Main St., Houston, Texas 77005, USA
| | - Lance Bigelow
- Biosciences Division, Midwest Center for Structural Genomics, Argonne National Laboratory , Bldg. 446/Rm. A104, 970 South Cass Avenue, Argonne, Illinois 60439, USA
| | | | - Robert Jedrzejczak
- Biosciences Division, Midwest Center for Structural Genomics, Argonne National Laboratory , Bldg. 446/Rm. A104, 970 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Gyorgy Babnigg
- Biosciences Division, Midwest Center for Structural Genomics, Argonne National Laboratory , Bldg. 446/Rm. A104, 970 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Craig A Bingman
- Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, USA
| | - Andrzej Joachimiak
- Biosciences Division, Midwest Center for Structural Genomics, Argonne National Laboratory , Bldg. 446/Rm. A104, 970 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Madan K Kharel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky , Lexington, Kentucky 40536, USA
| | - Shanteri Singh
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky , Lexington, Kentucky 40536, USA
| | - Jon S Thorson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky , Lexington, Kentucky 40536, USA
| | - George N Phillips
- Biosciences at Rice, Rice University , 6100 Main St., Houston, Texas 77005, USA
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40
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Forlani G, Makarova KS, Ruszkowski M, Bertazzini M, Nocek B. Evolution of plant δ(1)-pyrroline-5-carboxylate reductases from phylogenetic and structural perspectives. FRONTIERS IN PLANT SCIENCE 2015; 6:567. [PMID: 26284089 PMCID: PMC4522605 DOI: 10.3389/fpls.2015.00567] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/09/2015] [Indexed: 05/23/2023]
Abstract
Proline plays a crucial role in cell growth and stress responses, and its accumulation is essential for the tolerance of adverse environmental conditions in plants. Two routes are used to biosynthesize proline in plants. The main route uses glutamate as a precursor, while in the other route proline is derived from ornithine. The terminal step of both pathways, the conversion of δ(1)-pyrroline-5-carboxylate (P5C) to L-proline, is catalyzed by P5C reductase (P5CR) using NADH or NADPH as a cofactor. Since P5CRs are important housekeeping enzymes, they are conserved across all domains of life and appear to be relatively unaffected throughout evolution. However, global analysis of these enzymes unveiled significant functional diversity in the preference for cofactors (NADPH vs. NADH), variation in metal dependence and the differences in the oligomeric state. In our study we investigated evolutionary patterns through phylogenetic and structural analysis of P5CR representatives from all kingdoms of life, with emphasis on the plant species. We also attempted to correlate local sequence/structure variation among the functionally and structurally characterized members of the family.
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Affiliation(s)
- Giuseppe Forlani
- Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
| | - Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, BethesdaMD, USA
| | - Milosz Ruszkowski
- Synchrotron Radiation Research Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Argonne National Laboratory, ArgonneIL, USA
| | - Michele Bertazzini
- Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
| | - Boguslaw Nocek
- The Bioscience Division, Argonne National Laboratory, ArgonneIL, USA
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41
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Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA) and HIV-1 nef Genes in Escherichia coli. PLoS One 2015; 10:e0130446. [PMID: 26147991 PMCID: PMC4492947 DOI: 10.1371/journal.pone.0130446] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 05/20/2015] [Indexed: 11/19/2022] Open
Abstract
Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW) rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef), HIV-1 p24 (ca), and HIV-1 vif in NiCo21(DE3) E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes.
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42
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Fan Y, Tan K, Chhor G, Butler EK, Jedrzejczak RP, Missiakas D, Joachimiak A. EsxB, a secreted protein from Bacillus anthracis forms two distinct helical bundles. Protein Sci 2015; 24:1389-400. [PMID: 26032645 PMCID: PMC4570534 DOI: 10.1002/pro.2715] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/22/2015] [Accepted: 05/22/2015] [Indexed: 11/08/2022]
Abstract
The EsxB protein from Bacillus anthracis belongs to the WXG100 family, a group of proteins secreted by a specialized secretion system. We have determined the crystal structures of recombinant EsxB and discovered that the small protein (∼10 kDa), comprised of a helix-loop-helix (HLH) hairpin, is capable of associating into two different helical bundles. The two basic quaternary assemblies of EsxB are an antiparallel (AP) dimer and a rarely observed bisecting U (BU) dimer. This structural duality of EsxB is believed to originate from the heptad repeat sequence diversity of the first helix of its HLH hairpin, which allows for two alternative helix packing. The flexibility of EsxB and the ability to form alternative helical bundles underscore the possibility that this protein can serve as an adaptor in secretion and can form hetero-oligomeric helix bundle(s) with other secreted members of the WXG100 family, such as EsxW. The highly conserved WXG motif is located within the loop of the HLH hairpin and is mostly buried within the helix bundle suggesting that its role is mainly structural. The exact functions of the motif, including a proposed role as a secretion signal, remain unknown.
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Affiliation(s)
- Yao Fan
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, Illinois, 60439
| | - Kemin Tan
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, Illinois, 60439.,Department of Biosciences, Structural Biology Center, Argonne National Laboratory, Argonne, Illinois, 60439.,Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, Illinois, 60637
| | - Gekleng Chhor
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, Illinois, 60439
| | - Emily K Butler
- Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Argonne, Illinois, 60439.,Department of Microbiology, University of Chicago, Chicago, Illinois, 60637
| | - Robert P Jedrzejczak
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, Illinois, 60439
| | - Dominique Missiakas
- Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Argonne, Illinois, 60439.,Department of Microbiology, University of Chicago, Chicago, Illinois, 60637
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, Illinois, 60439.,Department of Biosciences, Structural Biology Center, Argonne National Laboratory, Argonne, Illinois, 60439.,Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, Illinois, 60637
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43
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Michalska K, Steen AD, Chhor G, Endres M, Webber AT, Bird J, Lloyd KG, Joachimiak A. New aminopeptidase from "microbial dark matter" archaeon. FASEB J 2015; 29:4071-9. [PMID: 26062601 DOI: 10.1096/fj.15-272906] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/02/2015] [Indexed: 02/04/2023]
Abstract
Marine sediments host a large population of diverse, heterotrophic, uncultured microorganisms with unknown physiologies that control carbon flow through organic matter decomposition. Recently, single-cell genomics uncovered new key players in these processes, such as the miscellaneous crenarchaeotal group. These widespread archaea encode putative intra- and extracellular proteases for the degradation of detrital proteins present in sediments. Here, we show that one of these enzymes is a self-compartmentalizing tetrameric aminopeptidase with a preference for cysteine and hydrophobic residues at the N terminus of the hydrolyzed peptide. The ability to perform detailed characterizations of enzymes from native subsurface microorganisms, without requiring that those organisms first be grown in pure culture, holds great promise for understanding key carbon transformations in the environment as well as identifying new enzymes for biomedical and biotechnological applications.
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Affiliation(s)
- Karolina Michalska
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Andrew D Steen
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Gekleng Chhor
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Michael Endres
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Austen T Webber
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Jordan Bird
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Karen G Lloyd
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
| | - Andrzej Joachimiak
- *Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois, USA; Department of Microbiology and Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee, USA; and Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA
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Tan K, Johnson PM, Stols L, Boubion B, Eschenfeldt W, Babnigg G, Hayes CS, Joachimiak A, Goulding CW. The structure of a contact-dependent growth-inhibition (CDI) immunity protein from Neisseria meningitidis MC58. Acta Crystallogr F Struct Biol Commun 2015; 71:702-9. [PMID: 26057799 PMCID: PMC4461334 DOI: 10.1107/s2053230x15006585] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 03/31/2015] [Indexed: 01/01/2023] Open
Abstract
Contact-dependent growth inhibition (CDI) is an important mechanism of intercellular competition between neighboring Gram-negative bacteria. CDI systems encode large surface-exposed CdiA effector proteins that carry a variety of C-terminal toxin domains (CdiA-CTs). All CDI(+) bacteria also produce CdiI immunity proteins that specifically bind to the cognate CdiA-CT and neutralize its toxin activity to prevent auto-inhibition. Here, the X-ray crystal structure of a CdiI immunity protein from Neisseria meningitidis MC58 is presented at 1.45 Å resolution. The CdiI protein has structural homology to the Whirly family of RNA-binding proteins, but appears to lack the characteristic nucleic acid-binding motif of this family. Sequence homology suggests that the cognate CdiA-CT is related to the eukaryotic EndoU family of RNA-processing enzymes. A homology model is presented of the CdiA-CT based on the structure of the XendoU nuclease from Xenopus laevis. Molecular-docking simulations predict that the CdiA-CT toxin active site is occluded upon binding to the CdiI immunity protein. Together, these observations suggest that the immunity protein neutralizes toxin activity by preventing access to RNA substrates.
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Affiliation(s)
- Kemin Tan
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA
- Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Parker M. Johnson
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA 92697, USA
| | - Lucy Stols
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Bryan Boubion
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA 92697, USA
| | - William Eschenfeldt
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Gyorgy Babnigg
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Christopher S. Hayes
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
- Biomolecular Science and Engineering Program, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Andrezj Joachimiak
- Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne, IL 60439, USA
- Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Celia W. Goulding
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA 92697, USA
- Department of Pharmaceutical Sciences, University of California Irvine, Irvine, CA 92697, USA
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Ruszkowski M, Nocek B, Forlani G, Dauter Z. The structure of Medicago truncatula δ(1)-pyrroline-5-carboxylate reductase provides new insights into regulation of proline biosynthesis in plants. FRONTIERS IN PLANT SCIENCE 2015; 6:869. [PMID: 26579138 PMCID: PMC4626632 DOI: 10.3389/fpls.2015.00869] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/01/2015] [Indexed: 05/18/2023]
Abstract
The two pathways for proline biosynthesis in higher plants share the last step, the conversion of δ(1)-pyrroline-5-carboxylate (P5C) to L-proline, which is catalyzed by P5C reductase (P5CR, EC 1.5.1.2) with the use of NAD(P)H as a coenzyme. There is increasing amount of evidence to suggest a complex regulation of P5CR activity at the post-translational level, yet the molecular basis of these mechanisms is unknown. Here we report the three-dimensional structure of the P5CR enzyme from the model legume Medicago truncatula (Mt). The crystal structures of unliganded MtP5CR decamer, and its complexes with the products NAD(+), NADP(+), and L-proline were refined using x-ray diffraction data (at 1.7, 1.85, 1.95, and 2.1 Å resolution, respectively). Based on the presented structural data, the coenzyme preference for NADPH over NADH was explained, and NADPH is suggested to be the only coenzyme used by MtP5CR in vivo. Furthermore, the insensitivity of MtP5CR to feed-back inhibition by proline, revealed by enzymatic analysis, was correlated with structural features. Additionally, a mechanism for the modulation of enzyme activity by chloride anions is discussed, as well as the rationale for the possible development of effective enzyme inhibitors.
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Affiliation(s)
- Milosz Ruszkowski
- Synchrotron Radiation Research Section, Macromolecular Crystallography Laboratory, National Cancer InstituteArgonne, IL, USA
- *Correspondence: Milosz Ruszkowski
| | - Boguslaw Nocek
- Biosciences Division, Argonne National Laboratory, The Structural Biology CenterArgonne, IL, USA
| | - Giuseppe Forlani
- Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
| | - Zbigniew Dauter
- Synchrotron Radiation Research Section, Macromolecular Crystallography Laboratory, National Cancer InstituteArgonne, IL, USA
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Forlani G, Bertazzini M, Zarattini M, Funck D, Ruszkowski M, Nocek B. Functional properties and structural characterization of rice δ(1)-pyrroline-5-carboxylate reductase. FRONTIERS IN PLANT SCIENCE 2015; 6:565. [PMID: 26284087 PMCID: PMC4517315 DOI: 10.3389/fpls.2015.00565] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 07/09/2015] [Indexed: 05/20/2023]
Abstract
The majority of plant species accumulate high intracellular levels of proline to cope with hyperosmotic stress conditions. Proline synthesis from glutamate is tightly regulated at both the transcriptional and the translational levels, yet little is known about the mechanisms for post-translational regulation of the enzymatic activities involved. The gene coding in rice (Oryza sativa L.) for δ(1)-pyrroline-5-carboxylate (P5C) reductase, the enzyme that catalyzes the second and final step in this pathway, was isolated and expressed in Escherichia coli. The structural and functional properties of the affinity-purified protein were characterized. As for most species, rice P5C reductase was able to use in vitro either NADH or NADPH as the electron donor. However, strikingly different effects of cations and anions were found depending on the pyridine nucleotide used, namely inhibition of NADH-dependent activity and stimulation of NADPH-dependent activity. Moreover, physiological concentrations of proline and NADP(+) were strongly inhibitory for the NADH-dependent reaction, whereas the NADPH-dependent activity was mildly affected. Our results suggest that only NADPH may be used in vivo and that stress-dependent variations in ion homeostasis and NADPH/NADP(+) ratio could modulate enzyme activity, being functional in promoting proline accumulation and potentially also adjusting NADPH consumption during the defense against hyperosmotic stress. The apparent molecular weight of the native protein observed in size exclusion chromatography indicated a high oligomerization state. We also report the first crystal structure of a plant P5C reductase at 3.40-Å resolution, showing a decameric quaternary assembly. Based on the structure, it was possible to identify dynamic structural differences among rice, human, and bacterial enzymes.
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Affiliation(s)
- Giuseppe Forlani
- Laboratory of Plant Physiology and Biochemistry, Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
- *Correspondence: Giuseppe Forlani, Laboratory of Plant Physiology and Biochemistry, Department of Life Science and Biotechnology, University of Ferrara, Via Luigi Borsari 46, Ferrara 44121, Italy,
| | - Michele Bertazzini
- Laboratory of Plant Physiology and Biochemistry, Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
- Plant Physiology and Biochemistry, Department of Biology, University of KonstanzKonstanz, Germany
| | - Marco Zarattini
- Laboratory of Plant Physiology and Biochemistry, Department of Life Science and Biotechnology, University of FerraraFerrara, Italy
| | - Dietmar Funck
- Plant Physiology and Biochemistry, Department of Biology, University of KonstanzKonstanz, Germany
| | - Milosz Ruszkowski
- Synchrotron Radiation Research Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Argonne National Laboratory, ArgonneIL, USA
| | - Bogusław Nocek
- Biosciences Division, Argonne National Laboratory, ArgonneIL, USA
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Hammerstrom TG, Horton LB, Swick MC, Joachimiak A, Osipiuk J, Koehler TM. Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity. Mol Microbiol 2014; 95:426-41. [PMID: 25402841 DOI: 10.1111/mmi.12867] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2014] [Indexed: 12/22/2022]
Abstract
The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthetic operon. AtxA activity is elevated during growth in media containing glucose and CO(2)/bicarbonate, and there is a positive correlation between the CO(2)/bicarbonate signal, AtxA activity and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His→Asp) and phosphoablative (His→Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (i) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (ii) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator, and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism.
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Affiliation(s)
- Troy G Hammerstrom
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX, USA
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Tan K, Chhor G, Binkowski TA, Jedrzejczak RP, Makowska-Grzyska M, Joachimiak A. Sensor domain of histidine kinase KinB of Pseudomonas: a helix-swapped dimer. J Biol Chem 2014; 289:12232-44. [PMID: 24573685 DOI: 10.1074/jbc.m113.514836] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The overproduction of polysaccharide alginate is responsible for the formation of mucus in the lungs of cystic fibrosis patients. Histidine kinase KinB of the KinB-AlgB two-component system in Pseudomonas aeruginosa acts as a negative regulator of alginate biosynthesis. The modular architecture of KinB is similar to other histidine kinases. However, its periplasmic signal sensor domain is unique and is found only in the Pseudomonas genus. Here, we present the first crystal structures of the KinB sensor domain. The domain is a dimer in solution, and in the crystal it shows an atypical dimer of a helix-swapped four-helix bundle. A positively charged cavity is formed on the dimer interface and involves several strictly conserved residues, including Arg-60. A phosphate anion is bound asymmetrically in one of the structures. In silico docking identified several monophosphorylated sugars, including β-D-fructose 6-phosphate and β-D-mannose 6-phosphate, a precursor and an intermediate of alginate synthesis, respectively, as potential KinB ligands. Ligand binding was confirmed experimentally. Conformational transition from a symmetric to an asymmetric structure and decreasing dimer stability caused by ligand binding may be a part of the signal transduction mechanism of the KinB-AlgB two-component system.
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Affiliation(s)
- Kemin Tan
- From the Midwest Center for Structural Genomics and
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