51
|
Jian Y, Jin Z, Qi S, Da X, Wang Z, Wang X, Zhou Q. An Alkynyl-Dangling Ru(II) Polypyridine Complex for Targeted Antimicrobial Photodynamic Therapy. Chemistry 2021; 28:e202103359. [PMID: 34890065 DOI: 10.1002/chem.202103359] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Indexed: 11/11/2022]
Abstract
To realize clinical application of antibacterial photodynamic therapy (aPDT), one of the most arduous challenges is how to render aPDT agents high selectivity against bacterial pathogens. In light of the fact that amino group-containing lipids are rich on the outer surfaces of Gram-positive bacteria, we herein constructed an alkynyl-dangling ruthenium(II) polypyridine complex (Ru2) to preferentially label Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) over mammalian cells via the amino-yne bio-orthogonal click reaction. Thanks to the strong singlet oxygen generation ability, Ru2 could photo-inactivate S. aureus and MRSA effectively and specifically. Phosphatidylethanolamine (PE) molecules also exist in mammalian cells but are not accessible for Ru2, leading to its poor binding/uptake and negligible cytotoxicity in the dark and upon irradiation towards mammalian cells as well as low hemolysis, all favorable for aPDT application.
Collapse
Affiliation(s)
- Yao Jian
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhihui Jin
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Shuang Qi
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xuwen Da
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhanhua Wang
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xuesong Wang
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Qianxiong Zhou
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| |
Collapse
|
52
|
Metabolic biorthogonal labeling and dSTORM imaging of peptidoglycan synthesis in Streptococcus pneumoniae. STAR Protoc 2021; 2:101006. [PMID: 34977669 PMCID: PMC8683770 DOI: 10.1016/j.xpro.2021.101006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Fluorescence microscopy is a method of choice for studying peptidoglycan assembly, but it presents two major challenges: the peptidoglycan must be labeled with a probe that will not perturb the physiological process, and the spatial resolution must reach the nanometer scale to reveal fine details of the synthesis process. This protocol meets both challenges by combining biorthogonal metabolic labeling of peptidoglycan in Streptococcus pneumoniae with super-resolution fluorescence microscopy (dSTORM), also providing cues to adapt it to other bacteria. For complete details on the use and execution of this protocol, please refer to Trouve et al. (2021). Peptidoglycan can be labeled with a clickable D-Ala-D-Ala dipeptide The labeled peptidoglycan can be conjugated to a clickable Alexa Fluor 647 dye Fluorescently labeled peptidoglycan can be observed at 30-nm resolution by dSTORM
Collapse
|
53
|
Ferraro NJ, Kim S, Im W, Pires MM. Systematic Assessment of Accessibility to the Surface of Staphylococcus aureus. ACS Chem Biol 2021; 16:2527-2536. [PMID: 34609132 DOI: 10.1021/acschembio.1c00604] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Proteins from bacterial foes, antimicrobial peptides, and host immune proteins must navigate past a dense layer of bacterial surface biomacromolecules to reach the peptidoglycan (PG) layer of Gram-positive bacteria. A subclass of molecules (e.g., antibiotics with intracellular targets) also must permeate through the PG (in a molecular sieving manner) to reach the cytoplasmic membrane. Despite the biological and therapeutic importance of surface accessibility, systematic analyses in live bacterial cells have been lacking. We describe a live cell fluorescence assay that is robust, shows a high level of reproducibility, and reports on the permeability of molecules to and within the PG scaffold. Moreover, our study shows that teichoic acids impede the permeability of molecules of a wide range of sizes and chemical composition.
Collapse
Affiliation(s)
- Noel J. Ferraro
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Seonghoon Kim
- School of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, Republic of Korea
| | - Wonpil Im
- Departments of Biological Sciences, Chemistry, and Bioengineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| |
Collapse
|
54
|
Papadopoulos AO, Ealand C, Gordhan BG, VanNieuwenhze M, Kana BD. Characterisation of a putative M23-domain containing protein in Mycobacterium tuberculosis. PLoS One 2021; 16:e0259181. [PMID: 34784363 PMCID: PMC8594824 DOI: 10.1371/journal.pone.0259181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 10/14/2021] [Indexed: 12/01/2022] Open
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis remains a global health concern, further compounded by the high rates of HIV-TB co-infection and emergence of multi- and extensive drug resistant TB, all of which have hampered efforts to eradicate this disease. As a result, novel anti-tubercular interventions are urgently required, with the peptidoglycan component of the M. tuberculosis cell wall emerging as an attractive drug target. Peptidoglycan M23 endopeptidases can function as active cell wall hydrolases or degenerate activators of hydrolases in a variety of bacteria, contributing to important processes such as bacterial growth, division and virulence. Herein, we investigate the function of the Rv0950-encoded putative M23 endopeptidase in M. tuberculosis. In silico analysis revealed that this protein is conserved in mycobacteria, with a zinc-binding catalytic site predictive of hydrolytic activity. Transcript analysis indicated that expression of Rv0950c was elevated during lag and log phases of growth and reduced in stationary phase. Deletion of Rv0950c yielded no defects in growth, colony morphology, antibiotic susceptibility or intracellular survival but caused a reduction in cell length. Staining with a monopeptide-derived fluorescent D-amino acid, which spatially reports on sites of active PG biosynthesis or repair, revealed an overall reduction in uptake of the probe in ΔRv0950c. When stained with a dipeptide probe in the presence of cell wall damaging agents, the ΔRv0950c mutant displayed reduced sidewall labelling. As bacterial peptidoglycan metabolism is important for survival and pathogenesis, the role of Rv0950c and other putative M23 endopeptidases in M. tuberculosis should be explored further.
Collapse
Affiliation(s)
- Andrea Olga Papadopoulos
- Faculty of Health Sciences, DSI/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, University of the Witwatersrand, National Health Laboratory Service, Johannesburg, South Africa
| | - Christopher Ealand
- Faculty of Health Sciences, DSI/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, University of the Witwatersrand, National Health Laboratory Service, Johannesburg, South Africa
| | - Bhavna Gowan Gordhan
- Faculty of Health Sciences, DSI/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, University of the Witwatersrand, National Health Laboratory Service, Johannesburg, South Africa
| | - Michael VanNieuwenhze
- Department of Chemistry, Indiana University Bloomington, Bloomington, Indiana, United States of America
| | - Bavesh Davandra Kana
- Faculty of Health Sciences, DSI/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, University of the Witwatersrand, National Health Laboratory Service, Johannesburg, South Africa
| |
Collapse
|
55
|
Unipolar Peptidoglycan Synthesis in the Rhizobiales Requires an Essential Class A Penicillin-Binding Protein. mBio 2021; 12:e0234621. [PMID: 34544272 PMCID: PMC8546619 DOI: 10.1128/mbio.02346-21] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Members of the Rhizobiales are polarly growing bacteria that lack homologs of the canonical Rod complex. To investigate the mechanisms underlying polar cell wall synthesis, we systematically probed the function of cell wall synthesis enzymes in the plant pathogen Agrobacterium tumefaciens. The development of fluorescent d-amino acid dipeptide (FDAAD) probes, which are incorporated into peptidoglycan by penicillin-binding proteins in A. tumefaciens, enabled us to monitor changes in growth patterns in the mutants. Use of these fluorescent cell wall probes and peptidoglycan compositional analysis demonstrate that a single class A penicillin-binding protein is essential for polar peptidoglycan synthesis. Furthermore, we find evidence of an additional mode of cell wall synthesis that requires ld-transpeptidase activity. Genetic analysis and cell wall targeting antibiotics reveal that the mechanism of unipolar growth is conserved in Sinorhizobium and Brucella. This work provides insights into unipolar peptidoglycan biosynthesis employed by the Rhizobiales during cell elongation.
Collapse
|
56
|
Tank RG, Lund VA, Kumar S, Turner RD, Lafage L, Pasquina Lemonche L, Bullough PA, Cadby A, Foster SJ, Hobbs JK. Correlative Super-Resolution Optical and Atomic Force Microscopy Reveals Relationships Between Bacterial Cell Wall Architecture and Synthesis in Bacillus subtilis. ACS NANO 2021; 15:16011-16018. [PMID: 34533301 PMCID: PMC8552488 DOI: 10.1021/acsnano.1c04375] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Indexed: 06/13/2023]
Abstract
Understanding how bacteria grow and divide requires insight into both the molecular-level dynamics of ultrastructure and the chemistry of the constituent components. Atomic force microscopy (AFM) can provide near molecular resolution images of biological systems but typically provides limited chemical information. Conversely, while super-resolution optical microscopy allows localization of particular molecules and chemistries, information on the molecular context is difficult to obtain. Here, we combine these approaches into STORMForce (stochastic optical reconstruction with atomic force microscopy) and the complementary SIMForce (structured illumination with atomic force microscopy), to map the synthesis of the bacterial cell wall structural macromolecule, peptidoglycan, during growth and division in the rod-shaped bacterium Bacillus subtilis. Using "clickable" d-amino acid incorporation, we fluorescently label and spatially localize a short and controlled period of peptidoglycan synthesis and correlate this information with high-resolution AFM of the resulting architecture. During division, septal synthesis occurs across its developing surface, suggesting a two-stage process with incorporation at the leading edge and with considerable in-filling behind. During growth, the elongation of the rod occurs through bands of synthesis, spaced by ∼300 nm, and corresponds to denser regions of the internal cell wall as revealed by AFM. Combining super-resolution optics and AFM can provide insights into the synthesis processes that produce the complex architectures of bacterial structural biopolymers.
Collapse
Affiliation(s)
- Raveen
K. G. Tank
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - Victoria A. Lund
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Sandip Kumar
- Department
of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Robert D. Turner
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
- Department
of Computer Science, University of Sheffield, Sheffield, S1 4DP, United Kingdom
| | - Lucia Lafage
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Laia Pasquina Lemonche
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Per A. Bullough
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Ashley Cadby
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
| | - Simon J. Foster
- Department
of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Jamie K. Hobbs
- Department
of Physics and Astronomy, University of
Sheffield, Sheffield S3 7RH, United Kingdom
- The
Florey Institute for Host−Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom
| |
Collapse
|
57
|
Brown AR, Wodzanowski KA, Santiago CC, Hyland SN, Follmar JL, Asare-Okai P, Grimes CL. Protected N-Acetyl Muramic Acid Probes Improve Bacterial Peptidoglycan Incorporation via Metabolic Labeling. ACS Chem Biol 2021; 16:1908-1916. [PMID: 34506714 DOI: 10.1021/acschembio.1c00268] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metabolic glycan probes have emerged as an excellent tool to investigate vital questions in biology. Recently, methodology to incorporate metabolic bacterial glycan probes into the cell wall of a variety of bacterial species has been developed. In order to improve this method, a scalable synthesis of the peptidoglycan precursors is developed here, allowing for access to essential peptidoglycan immunological fragments and cell wall building blocks. The question was asked if masking polar groups of the glycan probe would increase overall incorporation, a common strategy exploited in mammalian glycobiology. Here, we show, through cellular assays, that E. coli do not utilize peracetylated peptidoglycan substrates but do employ methyl esters. The 10-fold improvement of probe utilization indicates that (i) masking the carboxylic acid is favorable for transport and (ii) bacterial esterases are capable of removing the methyl ester for use in peptidoglycan biosynthesis. This investigation advances bacterial cell wall biology, offering a prescription on how to best deliver and utilize bacterial metabolic glycan probes.
Collapse
Affiliation(s)
- Ashley R. Brown
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Kimberly A. Wodzanowski
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Cintia C. Santiago
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Stephen N. Hyland
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Julianna L. Follmar
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - PapaNii Asare-Okai
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Catherine Leimkuhler Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, United States
| |
Collapse
|
58
|
Kelliher JL, Grunenwald CM, Abrahams RR, Daanen ME, Lew CI, Rose WE, Sauer JD. PASTA kinase-dependent control of peptidoglycan synthesis via ReoM is required for cell wall stress responses, cytosolic survival, and virulence in Listeria monocytogenes. PLoS Pathog 2021; 17:e1009881. [PMID: 34624065 PMCID: PMC8528326 DOI: 10.1371/journal.ppat.1009881] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/20/2021] [Accepted: 09/27/2021] [Indexed: 02/01/2023] Open
Abstract
Pathogenic bacteria rely on protein phosphorylation to adapt quickly to stress, including that imposed by the host during infection. Penicillin-binding protein and serine/threonine-associated (PASTA) kinases are signal transduction systems that sense cell wall integrity and modulate multiple facets of bacterial physiology in response to cell envelope stress. The PASTA kinase in the cytosolic pathogen Listeria monocytogenes, PrkA, is required for cell wall stress responses, cytosolic survival, and virulence, yet its substrates and downstream signaling pathways remain incompletely defined. We combined orthogonal phosphoproteomic and genetic analyses in the presence of a β-lactam antibiotic to define PrkA phosphotargets and pathways modulated by PrkA. These analyses synergistically highlighted ReoM, which was recently identified as a PrkA target that influences peptidoglycan (PG) synthesis, as an important phosphosubstrate during cell wall stress. We find that deletion of reoM restores cell wall stress sensitivities and cytosolic survival defects of a ΔprkA mutant to nearly wild-type levels. While a ΔprkA mutant is defective for PG synthesis during cell wall stress, a double ΔreoM ΔprkA mutant synthesizes PG at rates similar to wild type. In a mouse model of systemic listeriosis, deletion of reoM in a ΔprkA background almost fully restored virulence to wild-type levels. However, loss of reoM alone also resulted in attenuated virulence, suggesting ReoM is critical at some points during pathogenesis. Finally, we demonstrate that the PASTA kinase/ReoM cell wall stress response pathway is conserved in a related pathogen, methicillin-resistant Staphylococcus aureus. Taken together, our phosphoproteomic analysis provides a comprehensive overview of the PASTA kinase targets of an important model pathogen and suggests that a critical role of PrkA in vivo is modulating PG synthesis through regulation of ReoM to facilitate cytosolic survival and virulence. Many antibiotics target bacterial cell wall biosynthesis, justifying continued study of this process and the ways bacteria respond to cell wall insults during infection. Penicillin-binding protein and serine/threonine-associated (PASTA) kinases are master regulators of cell wall stress responses in bacteria and are conserved in several major pathogens, including Listeria monocytogenes, Staphylococcus aureus, and Mycobacterium tuberculosis. We previously showed that the PASTA kinase in L. monocytogenes, PrkA, is essential for the response to cell wall stress and for virulence. In this work, we combined proteomic and genetic approaches to identify PrkA substrates in L. monocytogenes. We show that regulation of one candidate from both screens, ReoM, increases synthesis of the cell wall component peptidoglycan and that this regulation is required for pathogenesis. We also demonstrate that the PASTA kinase-ReoM pathway regulates cell wall stress responses in another significant pathogen, methicillin-resistant S. aureus. Additionally, we uncover a PrkA-independent role for ReoM in vivo in L. monocytogenes, suggesting a need for nuanced modulation of peptidoglycan synthesis during infection. Cumulatively, this study provides new insight into how bacterial pathogens control cell wall synthesis during infection.
Collapse
Affiliation(s)
- Jessica L. Kelliher
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Caroline M. Grunenwald
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Rhiannon R. Abrahams
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - McKenzie E. Daanen
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Cassandra I. Lew
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Warren E. Rose
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - John-Demian Sauer
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
59
|
Hsieh PY, Meng FC, Guo CW, Hu KH, Shih YL, Cheng WC. Harnessing Fluorescent Moenomycin A Antibiotics for Bacterial Cell Wall Imaging Studies. Chembiochem 2021; 22:3462-3468. [PMID: 34606179 DOI: 10.1002/cbic.202100433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/30/2021] [Indexed: 11/11/2022]
Abstract
The imaging of peptidoglycan (PGN) dynamics in living bacteria facilitates the understanding of PGN biosynthesis and wall-targeting antibiotics. The main tools for imaging bacterial PGN are fluorescent probes, such as the well-known PGN metabolic labeling probes. However, fluorescent small-molecule probes for labeling key PGN-synthesizing enzymes, especially for transglycosylases (TGases), remain to be explored. In this work, the first imaging probe for labeling TGase in bacterial cell wall studies is reported. We synthesized various fluorescent MoeA-based molecules by derivatizing the natural antibiotic moenomycin A (MoeA), and used them to label TGases in living bacteria, monitor bacterial growth and division cycles by time-lapse imaging, and study cell wall growth in the mecA-carrying methicillin-resistant Staphylococcus aureus (MRSA) strains when the β-lactam-based probes were unsuitable.
Collapse
Affiliation(s)
- Pei-Yu Hsieh
- Institute of Biological Chemistry, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan
| | - Fan-Chun Meng
- Genomics Research Center, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan
| | - Chih-Wei Guo
- Genomics Research Center, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan
| | - Kung-Hsiang Hu
- Genomics Research Center, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan
| | - Yu-Ling Shih
- Institute of Biological Chemistry, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 106, Taiwan.,Department of Microbiology, College of Medicine, National Taiwan University, No.1, Sec 1. Jen Ai Rd., Taipei, 100, Taiwan
| | - Wei-Chieh Cheng
- Genomics Research Center, Academia Sinica, No. 128, Academia Road Sec. 2, Taipei, 115, Taiwan.,Department of Chemistry, National Cheng Kung University, No.1, University Road, Tainan, 701, Taiwan.,Department of Applied Chemistry, National Chiayi University, No. 300, Syuefu Road, Chiayi, 600, Taiwan.,Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, No.100, Shin-Chuan 1st Road, Kaohsiung, 807, Taiwan
| |
Collapse
|
60
|
Xia JT, Li L, Hu XP. Copper-Catalyzed Decarboxylative Propargylic Alkylation of Enol Carbonates: Stereoselective Synthesis of Quaternary α-Amino Acids. ACS Catal 2021. [DOI: 10.1021/acscatal.1c03421] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jin-Tao Xia
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ling Li
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiang-Ping Hu
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| |
Collapse
|
61
|
Grieshaber NA, Runac J, Turner S, Dean M, Appa C, Omsland A, Grieshaber SS. The sRNA Regulated Protein DdbA Is Involved in Development and Maintenance of the Chlamydia trachomatis EB Cell Form. Front Cell Infect Microbiol 2021; 11:692224. [PMID: 34368013 PMCID: PMC8343073 DOI: 10.3389/fcimb.2021.692224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/23/2021] [Indexed: 11/18/2022] Open
Abstract
The chlamydial small non coding RNA, IhtA, regulates the expression of both HctA and DdbA, the uncharacterized product of the C. trachomatis L2 CTL0322 gene. HctA is a small, highly basic, DNA binding protein that is expressed late in development and mediates the condensation of the genome during RB to EB differentiation. DdbA is conserved throughout the chlamydial lineage, and is predicted to express a small, basic, cytoplasmic protein. As it is common for sRNAs to regulate multiple mRNAs within the same physiological pathway, we hypothesize that DdbA, like HctA, is involved in RB to EB differentiation. Here, we show that DdbA is a DNA binding protein, however unlike HctA, DdbA does not contribute to genome condensation but instead likely has nuclease activity. Using a DdbA temperature sensitive mutant, we show that DdbAts creates inclusions indistinguishable from WT L2 in size and that early RB replication is likewise similar at the nonpermissive temperature. However, the number of DdbAts infectious progeny is dramatically lower than WT L2 overall, although production of EBs is initiated at a similar time. The expression of a late gene reporter construct followed live at 40°C indicates that late gene expression is severely compromised in the DdbAts strain. Viability assays, both in host cells and in axenic media indicate that the DdbAts strain is defective in the maintenance of EB infectivity. Additionally, using Whole Genome Sequencing we demonstrate that chromosome condensation is temporally separated from DNA replication during the RB to EB transition. Although DdbA does not appear to be directly involved in this process, our data suggest it is a DNA binding protein that is important in the production and maintenance of infectivity of the EB, perhaps by contributing to the remodeling of the EB chromosome.
Collapse
Affiliation(s)
- Nicole A. Grieshaber
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Justin Runac
- College of Dentistry, University of Florida, Gainesville, FL, United States
| | - Sierra Turner
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Marissa Dean
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Cody Appa
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Anders Omsland
- Paul G. Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Scott S. Grieshaber
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| |
Collapse
|
62
|
A Dynamic, Ring-Forming Bactofilin Critical for Maintaining Cell Size in the Obligate Intracellular Bacterium Chlamydia trachomatis. Infect Immun 2021; 89:e0020321. [PMID: 33941579 DOI: 10.1128/iai.00203-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bactofilins are polymer-forming cytoskeletal proteins that are widely conserved in bacteria. Members of this protein family have diverse functional roles such as orienting subcellular molecular processes, establishing cell polarity, and aiding in cell shape maintenance. Using sequence alignment to the conserved bactofilin domain, we identified a bactofilin ortholog, BacACT, in the obligate intracellular pathogen Chlamydia trachomatis. Chlamydia species are obligate intracellular bacteria that undergo a developmental cycle alternating between infectious nondividing elementary bodies (EBs) and noninfectious dividing reticulate bodies (RBs). As Chlamydia divides by a polarized division process, we hypothesized that BacACT may function to establish polarity in these unique bacteria. Utilizing a combination of fusion constructs and high-resolution fluorescence microscopy, we determined that BacACT forms dynamic, membrane-associated filament- and ring-like structures in Chlamydia's replicative RB form. Contrary to our hypothesis, these structures are distinct from the microbe's cell division machinery and do not colocalize with septal peptidoglycan or MreB, the major organizer of the bacterium's division complex. Bacterial two-hybrid assays demonstrated BacACT interacts homotypically but does not directly interact with proteins involved in cell division or peptidoglycan biosynthesis. To investigate the function of BacACT in chlamydial development, we constructed a conditional knockdown strain using a newly developed CRISPR interference system. We observed that reducing bacACT expression significantly increased chlamydial cell size. Normal RB morphology was restored when an additional copy of bacACT was expressed in trans during knockdown. These data reveal a novel function for chlamydial bactofilin in maintaining cell size in this obligate intracellular bacterium.
Collapse
|
63
|
Luong P, Dube DH. Dismantling the bacterial glycocalyx: Chemical tools to probe, perturb, and image bacterial glycans. Bioorg Med Chem 2021; 42:116268. [PMID: 34130219 DOI: 10.1016/j.bmc.2021.116268] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 12/20/2022]
Abstract
The bacterial glycocalyx is a quintessential drug target comprised of structurally distinct glycans. Bacterial glycans bear unusual monosaccharide building blocks whose proper construction is critical for bacterial fitness, survival, and colonization in the human host. Despite their appeal as therapeutic targets, bacterial glycans are difficult to study due to the presence of rare bacterial monosaccharides that are linked and modified in atypical manners. Their structural complexity ultimately hampers their analytical characterization. This review highlights recent advances in bacterial chemical glycobiology and focuses on the development of chemical tools to probe, perturb, and image bacterial glycans and their biosynthesis. Current technologies have enabled the study of bacterial glycosylation machinery even in the absence of detailed structural information.
Collapse
Affiliation(s)
- Phuong Luong
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA
| | - Danielle H Dube
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA.
| |
Collapse
|
64
|
Persistence Alters the Interaction between Chlamydia trachomatis and Its Host Cell. Infect Immun 2021; 89:e0068520. [PMID: 34001559 DOI: 10.1128/iai.00685-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
In response to stress, the obligate intracellular pathogen Chlamydia trachomatis stops dividing and halts its biphasic developmental cycle. The infectious, extracellular form of this bacterium is highly susceptible to killing by the host immune response, and by pausing development, Chlamydia can survive in an intracellular, "aberrant" state for extended periods of time. The relevance of these aberrant forms has long been debated, and many questions remain concerning how they contribute to the persistence and pathogenesis of the organism. Using reporter cell lines, fluorescence microscopy, and a dipeptide labeling strategy, we measured the ability of C. trachomatis to synthesize, assemble, and degrade peptidoglycan under various aberrance-inducing conditions. We found that all aberrance-inducing conditions affect chlamydial peptidoglycan and that some actually halt the biosynthesis pathway early enough to prevent the release of an immunostimulatory peptidoglycan component, muramyl tripeptide. In addition, utilizing immunofluorescence and electron microscopy, we determined that the induction of aberrance can detrimentally affect the development of the microbe's pathogenic vacuole (the inclusion). Taken together, our data indicate that aberrant forms of Chlamydia generated by different environmental stressors can be sorted into two broad categories based on their ability to continue releasing peptidoglycan-derived, immunostimulatory muropeptides and their ability to secrete effector proteins that are normally expressed at the mid- and late stages of the microbe's developmental cycle. Our findings reveal a novel, immunoevasive feature inherent to a subset of aberrant chlamydial forms and provide clarity and context to the numerous persistence mechanisms employed by these ancient, genetically reduced microbes.
Collapse
|
65
|
Bobrovsky PA, Moroz VD, Lavrenova VN, Manuvera VA, Lazarev VN. Inhibition of Chlamydial Infection by CRISPR/Cas9-SAM Mediated Enhancement of Human Peptidoglycan Recognition Proteins Gene Expression in HeLa Cells. BIOCHEMISTRY (MOSCOW) 2021; 85:1310-1318. [PMID: 33280575 DOI: 10.1134/s0006297920110036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The global problem of emerging resistance of microorganisms to antibiotics makes the search for new natural substances with antibacterial properties relevant. Such substances include peptidoglycan recognition proteins (PGLYRP), which are the components of the innate immunity of many organisms, including humans. These proteins have a unique mechanism of action that allows them to evade the resistance of bacteria to them, as well as to be active against both Gram-positive and Gram-negative bacteria. However, the use of antimicrobial recombinant proteins is not always advisable due to the complexity of local delivery of the proteins and their stability; in this regard it seems appropriate to activate the components of the innate immunity. The aim of this study was to increase the expression level of native peptidoglycan recognition protein genes in HeLa cells using genome-editing technology with synergistic activation mediators (CRISPR/Cas9-SAM) and evaluate antichlamydial effect of PGLYRP. We demonstrated activation of the chlamydial two-component gene system (ctcB-ctcC), which played a key role in the mechanism of action of the peptidoglycan recognition proteins. We generated the HeLa cell line transduced with lentiviruses encoding CRISPR/Cas9-SAM activation system with increased PGLYRP gene expression. It was shown that activation of the own peptidoglycan recognition proteins gene expression in the cell line caused inhibition of the chlamydial infection development. The proposed approach makes it possible to use the capabilities of innate immunity to combat infectious diseases caused by Gram-positive and Gram-negative bacteria.
Collapse
Affiliation(s)
- P A Bobrovsky
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia.
| | - V D Moroz
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - V N Lavrenova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - V A Manuvera
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - V N Lazarev
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| |
Collapse
|
66
|
Modifying TIMER to generate a slow-folding DsRed derivative for optimal use in quickly-dividing bacteria. PLoS Pathog 2021; 17:e1009284. [PMID: 34214139 PMCID: PMC8291646 DOI: 10.1371/journal.ppat.1009284] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 07/20/2021] [Accepted: 06/14/2021] [Indexed: 11/29/2022] Open
Abstract
It is now well appreciated that members of pathogenic bacterial populations exhibit heterogeneity in growth rates and metabolic activity, and it is known this can impact the ability to eliminate all members of the bacterial population during antibiotic treatment. It remains unclear which pathways promote slowed bacterial growth within host tissues, primarily because it has been difficult to identify and isolate slow growing bacteria from host tissues for downstream analyses. To overcome this limitation, we have developed a novel variant of TIMER, a slow-folding fluorescent protein, named DsRed42, to identify subsets of slowly dividing bacteria within host tissues. The original TIMER folds too slowly for fluorescence accumulation in quickly replicating bacterial species (Escherichia coli, Yersinia pseudotuberculosis), however DsRed42 accumulates red fluorescence in late stationary phase cultures of E. coli and Y. pseudotuberculosis. We show DsRed42 signal also accumulates during exposure to sources of nitric oxide (NO), suggesting DsRed42 signal detects growth-arrested bacterial cells. In a mouse model of Y. pseudotuberculosis deep tissue infection, DsRed42 signal was detected, and primarily accumulates in bacteria expressing markers of stationary phase growth. There was no significant overlap between DsRed42 signal and NO-exposed subpopulations of bacteria within host tissues, suggesting NO stress was transient, allowing bacteria to recover from this stress and resume replication. This novel DsRed42 variant represents a tool that will enable additional studies of slow-growing subpopulations of bacteria, specifically within bacterial species that quickly divide. We have generated a variant of TIMER that can be used to mark slow-growing subsets of Yersinia pseudotuberculosis, which has a relatively short division time, similar to E. coli. We used a combination of site-directed and random mutagenesis to generate DsRed42, which has red fluorescent signal accumulation in post-exponential or stationary phase cells. Since this variant accumulates only red fluorescence, it is no longer a TIMER protein, and is more appropriately termed DsRed42. We found that nitric oxide (NO) stress is sufficient to promote DsRed42 signal accumulation in culture, however within host tissues, DsRed42 signal correlates with a stationary phase reporter (dps). These results suggest NO may cause an immediate arrest in bacterial cell division, but during growth in host tissues exposure to NO is transient, allowing bacteria to recover from this stress and resume cell division. Thus instead of indicating a response to host stressors, DsRed42 signal accumulation within host tissues appears to identify slow-growing cells that are experiencing nutrient limitation.
Collapse
|
67
|
Sher JW, Lim HC, Bernhardt TG. Polar Growth in Corynebacterium glutamicum Has a Flexible Cell Wall Synthase Requirement. mBio 2021; 12:e0068221. [PMID: 34098735 PMCID: PMC8262863 DOI: 10.1128/mbio.00682-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/03/2021] [Indexed: 12/30/2022] Open
Abstract
Members of the Corynebacterineae suborder of bacteria, including major pathogens such as Mycobacterium tuberculosis, grow via the insertion of new cell wall peptidoglycan (PG) material at their poles. This mode of elongation differs from that used by Escherichia coli and other more well-studied model organisms that grow by inserting new PG at dispersed sites along their cell body. Dispersed cell elongation is known to strictly require the SEDS-type PG synthase called RodA, whereas the other major class of PG synthases called class A penicillin-binding proteins (aPBPs) are not required for this mode of growth. Instead, they are thought to be important for maintaining the integrity of the PG matrix in organisms growing by dispersed elongation. In contrast, based on prior genetic studies in M. tuberculosis and related members of the Corynebacterineae suborder, the aPBPs are widely believed to be essential for polar growth, with RodA being dispensable. However, polar growth has not been directly assessed in mycobacterial or corynebacterial mutants lacking aPBP-type PG synthases. We therefore investigated the relative roles of aPBPs and RodA in polar growth using Corynebacterium glutamicum as a model member of Corynebacterineae. Notably, we discovered that the aPBPs are dispensable for polar growth and that this growth mode can be mediated by either an aPBP-type or a SEDS-type enzyme functioning as the sole elongation PG synthase. Thus, our results reveal that the mechanism of polar elongation is fundamentally flexible and, unlike dispersed elongation, can be effectively mediated in C. glutamicum by either a SEDS-bPBP or an aPBP-type synthase. IMPORTANCE The Corynebacterineae suborder includes a number of major bacterial pathogens. These organisms grow by polar extension unlike most well-studied model bacteria, which grow by inserting wall material at dispersed sites along their length. A better understanding of polar growth promises to uncover new avenues for targeting mycobacterial and corynebacterial infections. Here, we investigated the roles of the different classes of cell wall synthases for polar growth using Corynebacterium glutamicum as a model. We discovered that the polar growth mechanism is surprisingly flexible in this organism and, unlike dispersed synthesis, can function using either of the two known types of cell wall synthase enzymes.
Collapse
Affiliation(s)
- Joel W. Sher
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Hoong Chuin Lim
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Thomas G. Bernhardt
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
68
|
Taylor JA, Santiago CC, Gray J, Wodzanowski KA, DeMeester KE, Biboy J, Vollmer W, Grimes CL, Salama NR. Localizing Peptidoglycan Synthesis in Helicobacter pylori using Clickable Metabolic Probes. Curr Protoc 2021; 1:e80. [PMID: 33844460 DOI: 10.1002/cpz1.80] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The bacterial cell wall, composed of peptidoglycan (PG), provides structural integrity for the cell and is responsible for cell shape in most bacteria. Here we present tools to study the cell wall using a clickable PG-specific sugar, 2-alkyne muramic acid (MurNAc-alk), as a metabolic probe. Here we present a new reaction pathway for generating MurNAc-alk. We also include protocols for labeling PG synthesis in Helicobacter pylori, determining the identity of the labeled muropeptides using LC-MS/MS, sample preparation of cells labeled for a short fraction of the doubling time, and visualization using 3D structured illumination microscopy. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Alternative synthesis of MurNAc-alk (direct coupling) Support Protocol 1: Growing Helicobacter pylori in liquid culture Support Protocol 2: Fosfomycin rescue assay Basic Protocol 2: Mass spectrometry (MS) analysis to determine incorporation of MurNAc-alk within the peptidoglycan of H. pylori Support Protocol 3: Hayashi test to determine if SDS is present in the supernatant of peptidoglycan preparations Support Protocol 4: Creating custom cytocentrifuge units for use in a swinging-bucket tabletop centrifuge Basic Protocol 3: Labeling H. pylori with MurNAc-alk or D-Ala-alk Basic Protocol 4: Structured illumination microscopy (SIM) imaging on the DeltaVision OMX.
Collapse
Affiliation(s)
- Jennifer A Taylor
- Department of Microbiology, University of Washington, Seattle, Washington.,Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Cintia C Santiago
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware
| | - Joe Gray
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | - Kristen E DeMeester
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Catherine L Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware.,Department of Biological Sciences, University of Delaware, Newark, Delaware
| | - Nina R Salama
- Department of Microbiology, University of Washington, Seattle, Washington.,Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| |
Collapse
|
69
|
Huang Y, Chen W, Chung J, Yin J, Yoon J. Recent progress in fluorescent probes for bacteria. Chem Soc Rev 2021; 50:7725-7744. [PMID: 34013918 DOI: 10.1039/d0cs01340d] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Food fermentation, antibiotics, and pollutant degradation are closely related to bacteria. Bacteria play an irreplaceable role in life. However, some bacteria seriously threaten human health and cause large-scale infectious diseases. Therefore, there is a pressing need to develop strategies to accurately monitor bacteria. Technology based on molecular probes and fluorescence imaging is noninvasive, results in little damage, and has high specificity and sensitivity, so it has been widely applied in the detection of bacteria. In this review, we summarize the recent progress in bacterial detection using fluorescence. In particular, we generalize the mechanisms commonly used to design organic fluorescent probes for detecting and imaging bacteria. Moreover, a perspective regarding fluorescent probes for bacterial detection is discussed.
Collapse
Affiliation(s)
- Yurou Huang
- Key Laboratory of Pesticide and Chemical Biology, Ministry of education, Hubei International Scientific and technological cooperation Base of Pesticide and Green Synthesis, International Joint research center for Intelligent Biosensing Technology and Health, College of chemistry, Central China Normal University, Wuhan 430079, P. R. China and Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Weijie Chen
- Key Laboratory of Pesticide and Chemical Biology, Ministry of education, Hubei International Scientific and technological cooperation Base of Pesticide and Green Synthesis, International Joint research center for Intelligent Biosensing Technology and Health, College of chemistry, Central China Normal University, Wuhan 430079, P. R. China and Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Jeewon Chung
- Department of Chemistry and Nano Science, Ewha Womans University, 11-1 Daehyon-Dong, Sodaemun-Ku, Seoul 120-750, Korea.
| | - Jun Yin
- Key Laboratory of Pesticide and Chemical Biology, Ministry of education, Hubei International Scientific and technological cooperation Base of Pesticide and Green Synthesis, International Joint research center for Intelligent Biosensing Technology and Health, College of chemistry, Central China Normal University, Wuhan 430079, P. R. China and Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei University, Wuhan 430062, P. R. China
| | - Juyoung Yoon
- Department of Chemistry and Nano Science, Ewha Womans University, 11-1 Daehyon-Dong, Sodaemun-Ku, Seoul 120-750, Korea.
| |
Collapse
|
70
|
Trouve J, Zapun A, Arthaud C, Durmort C, Di Guilmi AM, Söderström B, Pelletier A, Grangeasse C, Bourgeois D, Wong YS, Morlot C. Nanoscale dynamics of peptidoglycan assembly during the cell cycle of Streptococcus pneumoniae. Curr Biol 2021; 31:2844-2856.e6. [PMID: 33989523 DOI: 10.1016/j.cub.2021.04.041] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/09/2021] [Accepted: 04/16/2021] [Indexed: 12/15/2022]
Abstract
Dynamics of cell elongation and septation are key determinants of bacterial morphogenesis. These processes are intimately linked to peptidoglycan synthesis performed by macromolecular complexes called the elongasome and the divisome. In rod-shaped bacteria, cell elongation and septation, which are dissociated in time and space, have been well described. By contrast, in ovoid-shaped bacteria, the dynamics and relationships between these processes remain poorly understood because they are concomitant and confined to a nanometer-scale annular region at midcell. Here, we set up a metabolic peptidoglycan labeling approach using click chemistry to image peptidoglycan synthesis by single-molecule localization microscopy in the ovoid bacterium Streptococcus pneumoniae. Our nanoscale-resolution data reveal spatiotemporal features of peptidoglycan assembly and fate along the cell cycle and provide geometrical parameters that we used to construct a morphogenesis model of the ovoid cell. These analyses show that septal and peripheral peptidoglycan syntheses first occur within a single annular region that later separates in two concentric regions and that elongation persists after septation is completed. In addition, our data reveal that freshly synthesized peptidoglycan is remodeled all along the cell cycle. Altogether, our work provides evidence that septal peptidoglycan is synthesized from the beginning of the cell cycle and is constantly remodeled through cleavage and insertion of material at its periphery. The ovoid-cell morphogenesis would thus rely on the relative dynamics between peptidoglycan synthesis and cleavage rather than on the existence of two distinct successive phases of peripheral and septal synthesis.
Collapse
Affiliation(s)
- Jennyfer Trouve
- Univ. Grenoble Alpes, CNRS, CEA, IBS, 38000 Grenoble, France
| | - André Zapun
- Univ. Grenoble Alpes, CNRS, CEA, IBS, 38000 Grenoble, France
| | | | - Claire Durmort
- Univ. Grenoble Alpes, CNRS, CEA, IBS, 38000 Grenoble, France
| | | | - Bill Söderström
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia; Structural Cellular Biology Unit, Okinawa Institute of Science and Technology, 904-0495 Okinawa, Japan
| | - Anais Pelletier
- Molecular Microbiology and Structural Biochemistry (MMSB), CNRS, Univ. Lyon 1, UMR 5086, Lyon 69007, France
| | - Christophe Grangeasse
- Molecular Microbiology and Structural Biochemistry (MMSB), CNRS, Univ. Lyon 1, UMR 5086, Lyon 69007, France
| | | | | | - Cecile Morlot
- Univ. Grenoble Alpes, CNRS, CEA, IBS, 38000 Grenoble, France.
| |
Collapse
|
71
|
Mehla J, Liechti G, Morgenstein RM, Caufield JH, Hosseinnia A, Gagarinova A, Phanse S, Goodacre N, Brockett M, Sakhawalkar N, Babu M, Xiao R, Montelione GT, Vorobiev S, den Blaauwen T, Hunt JF, Uetz P. ZapG (YhcB/DUF1043), a novel cell division protein in gamma-proteobacteria linking the Z-ring to septal peptidoglycan synthesis. J Biol Chem 2021; 296:100700. [PMID: 33895137 PMCID: PMC8163987 DOI: 10.1016/j.jbc.2021.100700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 04/14/2021] [Accepted: 04/21/2021] [Indexed: 01/26/2023] Open
Abstract
YhcB, a poorly understood protein conserved across gamma-proteobacteria, contains a domain of unknown function (DUF1043) and an N-terminal transmembrane domain. Here, we used an integrated approach including X-ray crystallography, genetics, and molecular biology to investigate the function and structure of YhcB. The Escherichia coli yhcB KO strain does not grow at 45 °C and is hypersensitive to cell wall–acting antibiotics, even in the stationary phase. The deletion of yhcB leads to filamentation, abnormal FtsZ ring formation, and aberrant septum development. The Z-ring is essential for the positioning of the septa and the initiation of cell division. We found that YhcB interacts with proteins of the divisome (e.g., FtsI, FtsQ) and elongasome (e.g., RodZ, RodA). Seven of these interactions are also conserved in Yersinia pestis and/or Vibrio cholerae. Furthermore, we mapped the amino acid residues likely involved in the interactions of YhcB with FtsI and RodZ. The 2.8 Å crystal structure of the cytosolic domain of Haemophilus ducreyi YhcB shows a unique tetrameric α-helical coiled-coil structure likely to be involved in linking the Z-ring to the septal peptidoglycan-synthesizing complexes. In summary, YhcB is a conserved and conditionally essential protein that plays a role in cell division and consequently affects envelope biogenesis. Based on these findings, we propose to rename YhcB to ZapG (Z-ring-associated protein G). This study will serve as a starting point for future studies on this protein family and on how cells transit from exponential to stationary survival.
Collapse
Affiliation(s)
- Jitender Mehla
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, Virginia, USA.
| | - George Liechti
- Department of Microbiology and Immunology, Henry Jackson Foundation, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Randy M Morgenstein
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - J Harry Caufield
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Ali Hosseinnia
- Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan, Canada
| | - Alla Gagarinova
- Department of Biochemistry, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Sadhna Phanse
- Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan, Canada
| | - Norman Goodacre
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Mary Brockett
- Department of Microbiology and Immunology, Henry Jackson Foundation, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Neha Sakhawalkar
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Mohan Babu
- Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan, Canada
| | - Rong Xiao
- Nexomics Biosciences Inc., Rocky Hill, New Jersey, USA; Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Gaetano T Montelione
- Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Sergey Vorobiev
- Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Biological Sciences, Columbia University, New York, New York, USA
| | - Tanneke den Blaauwen
- Bacterial Cell Biology & Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - John F Hunt
- Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA; Department of Biological Sciences, Columbia University, New York, New York, USA
| | - Peter Uetz
- Center for the Study of Biological Complexity, Virginia Commonwealth University, Richmond, Virginia, USA.
| |
Collapse
|
72
|
Ignacio BJ, Bakkum T, Bonger KM, Martin NI, van Kasteren SI. Metabolic labeling probes for interrogation of the host-pathogen interaction. Org Biomol Chem 2021; 19:2856-2870. [PMID: 33725048 DOI: 10.1039/d0ob02517h] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Bacterial infections are still one of the leading causes of death worldwide; despite the near-ubiquitous availability of antibiotics. With antibiotic resistance on the rise, there is an urgent need for novel classes of antibiotic drugs. One particularly troublesome class of bacteria are those that have evolved highly efficacious mechanisms for surviving inside the host. These contribute to their virulence by immune evasion, and make them harder to treat with antibiotics due to their residence inside intracellular membrane-limited compartments. This has sparked the development of new chemical reporter molecules and bioorthogonal probes that can be metabolically incorporated into bacteria to provide insights into their activity status. In this review, we provide an overview of several classes of metabolic labeling probes capable of targeting either the peptidoglycan cell wall, the mycomembrane of mycobacteria and corynebacteria, or specific bacterial proteins. In addition, we highlight several important insights that have been made using these metabolic labeling probes.
Collapse
Affiliation(s)
- Bob J Ignacio
- Institute for Molecules and Materials, Radbout Universiteit, Nijmegen, Gelderland, Netherlands
| | | | | | | | | |
Collapse
|
73
|
Shima K, Kaufhold I, Eder T, Käding N, Schmidt N, Ogunsulire IM, Deenen R, Köhrer K, Friedrich D, Isay SE, Grebien F, Klinger M, Richer BC, Günther UL, Deepe GS, Rattei T, Rupp J. Regulation of the Mitochondrion-Fatty Acid Axis for the Metabolic Reprogramming of Chlamydia trachomatis during Treatment with β-Lactam Antimicrobials. mBio 2021; 12:e00023-21. [PMID: 33785629 PMCID: PMC8092193 DOI: 10.1128/mbio.00023-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/23/2021] [Indexed: 12/18/2022] Open
Abstract
Infection with the obligate intracellular bacterium Chlamydia trachomatis is the most common bacterial sexually transmitted disease worldwide. Since no vaccine is available to date, antimicrobial therapy is the only alternative in C. trachomatis infection. However, changes in chlamydial replicative activity and the occurrence of chlamydial persistence caused by diverse stimuli have been proven to impair treatment effectiveness. Here, we report the mechanism for C. trachomatis regulating host signaling processes and mitochondrial function, which can be used for chlamydial metabolic reprogramming during treatment with β-lactam antimicrobials. Activation of signal transducer and activator of transcription 3 (STAT3) is a well-known host response in various bacterial and viral infections. In C. trachomatis infection, inactivation of STAT3 by host protein tyrosine phosphatases increased mitochondrial respiration in both the absence and presence of β-lactam antimicrobials. However, during treatment with β-lactam antimicrobials, C. trachomatis increased the production of citrate as well as the activity of host ATP-citrate lyase involved in fatty acid synthesis. Concomitantly, chlamydial metabolism switched from the tricarboxylic acid cycle to fatty acid synthesis. This metabolic switch was a unique response in treatment with β-lactam antimicrobials and was not observed in gamma interferon (IFN-γ)-induced persistent infection. Inhibition of fatty acid synthesis was able to attenuate β-lactam-induced chlamydial persistence. Our findings highlight the importance of the mitochondrion-fatty acid interplay for the metabolic reprogramming of C. trachomatis during treatment with β-lactam antimicrobials.IMPORTANCE The mitochondrion generates most of the ATP in eukaryotic cells, and its activity is used for controlling the intracellular growth of Chlamydia trachomatis Furthermore, mitochondrial activity is tightly connected to host fatty acid synthesis that is indispensable for chlamydial membrane biogenesis. Phospholipids, which are composed of fatty acids, are the central components of the bacterial membrane and play a crucial role in the protection against antimicrobials. Chlamydial persistence that is induced by various stimuli is clinically relevant. While one of the well-recognized inducers, β-lactam antimicrobials, has been used to characterize chlamydial persistence, little is known about the role of mitochondria in persistent infection. Here, we demonstrate how C. trachomatis undergoes metabolic reprogramming to switch from the tricarboxylic acid cycle to fatty acid synthesis with promoted host mitochondrial activity in response to treatment with β-lactam antimicrobials.
Collapse
Affiliation(s)
- Kensuke Shima
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Inga Kaufhold
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Thomas Eder
- Division of Computational Systems Biology, University Vienna, Vienna, Austria
- Institute for Medical Biochemistry, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Nadja Käding
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Nis Schmidt
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Iretiolu M Ogunsulire
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - René Deenen
- Biological and Medical Research Center (BMFZ), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Karl Köhrer
- Biological and Medical Research Center (BMFZ), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Dirk Friedrich
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Sophie E Isay
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
| | - Florian Grebien
- Institute for Medical Biochemistry, University of Veterinary Medicine Vienna, Vienna, Austria
| | | | - Barbara C Richer
- Institute of Chemistry and Metabolomics, University of Lübeck, Lübeck, Germany
| | - Ulrich L Günther
- Institute of Chemistry and Metabolomics, University of Lübeck, Lübeck, Germany
| | - George S Deepe
- Division of Infectious Diseases, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Thomas Rattei
- Division of Computational Systems Biology, University Vienna, Vienna, Austria
| | - Jan Rupp
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Lübeck, Germany
| |
Collapse
|
74
|
Murray SM, McKay PF. Chlamydia trachomatis: Cell biology, immunology and vaccination. Vaccine 2021; 39:2965-2975. [PMID: 33771390 DOI: 10.1016/j.vaccine.2021.03.043] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 02/06/2023]
Abstract
Chlamydia trachomatis is the causative agent of a highly prevalent sexually transmitted bacterial disease and is associated with a number of severe disease complications. Current therapy options are successful at treating disease, but patients are left without protective immunity and do not benefit the majority asymptomatic patients who do not seek treatment. As such, there is a clear need for a broad acting, protective vaccine that can prevent transmission and protect against symptomatic disease presentation. There are three key elements that underlie successful vaccine development: 1) Chlamydia biology and immune-evasion adaptations, 2) the correlates of protection that prevent disease in natural and experimental infection, 3) reflection upon the evidence provided by previous vaccine attempts. In this review, we give an overview of the unique intra-cellular biology of C. trachomatis and give insight into the dynamic combination of adaptations that allow Chlamydia to subvert host immunity and survive within the cell. We explore the current understanding of chlamydial immunity in animal models and in humans and characterise the key immune correlates of protection against infection. We discuss in detail the specific immune interactions involved in protection, with relevance placed on the CD4+ T lymphocyte and B lymphocyte responses that are key to pathogen clearance. Finally, we provide a timeline of C. trachomatis vaccine research to date and evaluate the successes and failures in development so far. With insight from these three key elements of research, we suggest potential solutions for chlamydial vaccine development and promising avenues for further exploration.
Collapse
Affiliation(s)
- Sam M Murray
- Department of Infectious Diseases, Imperial College London, Norfolk Place, London W2 1PG, UK.
| | - Paul F McKay
- Department of Infectious Diseases, Imperial College London, Norfolk Place, London W2 1PG, UK.
| |
Collapse
|
75
|
Kunz TC, Rühling M, Moldovan A, Paprotka K, Kozjak-Pavlovic V, Rudel T, Fraunholz M. The Expandables: Cracking the Staphylococcal Cell Wall for Expansion Microscopy. Front Cell Infect Microbiol 2021; 11:644750. [PMID: 33796486 PMCID: PMC8008081 DOI: 10.3389/fcimb.2021.644750] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/08/2021] [Indexed: 12/03/2022] Open
Abstract
Expansion Microscopy (ExM) is a novel tool improving the resolution of fluorescence microscopy by linking the sample into a hydrogel that gets physically expanded in water. Previously, we have used ExM to visualize the intracellular Gram-negative pathogens Chlamydia trachomatis, Simkania negevensis, and Neisseria gonorrhoeae. Gram-positive bacteria have a rigid and thick cell wall that impedes classic expansion strategies. Here we developed an approach, which included a series of enzymatic treatments resulting in isotropic 4× expansion of the Gram-positive pathogen Staphylococcus aureus. We further demonstrate the suitability of the technique for imaging of planktonic bacteria as well as endocytosed, intracellular bacteria at a spatial resolution of approximately 60 nm with conventional confocal laser scanning microscopy.
Collapse
Affiliation(s)
- Tobias C Kunz
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Marcel Rühling
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Adriana Moldovan
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Kerstin Paprotka
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Vera Kozjak-Pavlovic
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Thomas Rudel
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Martin Fraunholz
- Department of Microbiology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| |
Collapse
|
76
|
Gilmore MC, Ritzl-Rinkenberger B, Cava F. An updated toolkit for exploring bacterial cell wall structure and dynamics. Fac Rev 2021; 10:14. [PMID: 33659932 PMCID: PMC7894271 DOI: 10.12703/r/10-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The bacterial cell wall is made primarily from peptidoglycan, a complex biomolecule which forms a bag-like exoskeleton that envelops the cell. As it is unique to bacteria and typically essential for their growth and survival, it represents one of the most successful targets for antibiotics. Although peptidoglycan has been studied intensively for over 50 years, the past decade has seen major steps in our understanding of this molecule because of the advent of new analytical and imaging methods. Here, we outline the most recent developments in tools that have helped to elucidate peptidoglycan structure and dynamics.
Collapse
Affiliation(s)
- Michael C Gilmore
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Barbara Ritzl-Rinkenberger
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, Umeå, Sweden
| |
Collapse
|
77
|
Genome copy number regulates inclusion expansion, septation, and infectious developmental form conversion in Chlamydia trachomatis. J Bacteriol 2021; 203:JB.00630-20. [PMID: 33431433 PMCID: PMC8095454 DOI: 10.1128/jb.00630-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
DNA replication is essential for the growth and development of Chlamydia trachomatis, however it is unclear how this process contributes to and is controlled by the pathogen's biphasic lifecycle. While inhibitors of transcription, translation, cell division, and glucose-6-phosphate transport all negatively affect chlamydial intracellular development, the effects of directly inhibiting DNA polymerase have never been examined. We isolated a temperature sensitive dnaE mutant (dnaEts ) that exhibits a ∼100-fold reduction in genome copy number at the non-permissive temperature (40°C), but replicates similarly to the parent at the permissive temperature of 37°C. We measured higher ratios of genomic DNA nearer the origin of replication than the terminus in dnaEts at 40°C, indicating that this replication deficiency is due to a defect in DNA polymerase processivity. dnaEts formed fewer and smaller pathogenic vacuoles (inclusions) at 40°C, and the bacteria appeared enlarged and exhibited defects in cell division. The bacteria also lacked both discernable peptidoglycan and polymerized MreB, the major cell division organizing protein in Chlamydia responsible for nascent peptidoglycan biosynthesis. We also found that absolute genome copy number, rather than active genome replication, was sufficient for infectious progeny production. Deficiencies in both genome replication and inclusion expansion reversed when dnaEts was shifted from 40°C to 37°C early in infection, and intragenic suppressor mutations in dnaE also restored dnaEts genome replication and inclusion expansion at 40°C. Overall, our results show that genome replication in C. trachomatis is required for inclusion expansion, septum formation, and the transition between the microbe's replicative and infectious forms.SIGNIFICANCE Chlamydiae transition between infectious, extracellular elementary bodies (EBs) and non-infectious, intracellular reticulate bodies (RBs). Some checkpoints that govern transitions in chlamydial development have been identified, but the extent to which genome replication plays a role in regulating the pathogen's infectious cycle has not been characterized. We show that genome replication is dispensable for EB to RB conversion, but is necessary for RB proliferation, division septum formation, and inclusion expansion. We use new methods to investigate developmental checkpoints and dependencies in Chlamydia that facilitate the ordering of events in the microbe's biphasic life cycle. Our findings suggest that Chlamydia utilizes feedback inhibition to regulate core metabolic processes during development, likely an adaptation to intracellular stress and a nutrient-limiting environment.
Collapse
|
78
|
García-Heredia A, Kado T, Sein CE, Puffal J, Osman SH, Judd J, Gray TA, Morita YS, Siegrist MS. Membrane-partitioned cell wall synthesis in mycobacteria. eLife 2021; 10:e60263. [PMID: 33544079 PMCID: PMC7864634 DOI: 10.7554/elife.60263] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 01/20/2021] [Indexed: 01/16/2023] Open
Abstract
Many antibiotics target the assembly of cell wall peptidoglycan, an essential, heteropolymeric mesh that encases most bacteria. In rod-shaped bacteria, cell wall elongation is spatially precise yet relies on limited pools of lipid-linked precursors that generate and are attracted to membrane disorder. By tracking enzymes, substrates, and products of peptidoglycan biosynthesis in Mycobacterium smegmatis, we show that precursors are made in plasma membrane domains that are laterally and biochemically distinct from sites of cell wall assembly. Membrane partitioning likely contributes to robust, orderly peptidoglycan synthesis, suggesting that these domains help template peptidoglycan synthesis. The cell wall-organizing protein DivIVA and the cell wall itself promote domain homeostasis. These data support a model in which the peptidoglycan polymer feeds back on its membrane template to maintain an environment conducive to directional synthesis. Our findings are applicable to rod-shaped bacteria that are phylogenetically distant from M. smegmatis, indicating that horizontal compartmentalization of precursors may be a general feature of bacillary cell wall biogenesis.
Collapse
Affiliation(s)
- Alam García-Heredia
- Molecular and Cellular Biology Graduate Program, University of MassachusettsAmherstUnited States
| | - Takehiro Kado
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - Caralyn E Sein
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - Julia Puffal
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - Sarah H Osman
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - Julius Judd
- Division of Genetics, Wadsworth Center, New York State Department of HealthAlbanyUnited States
| | - Todd A Gray
- Division of Genetics, Wadsworth Center, New York State Department of HealthAlbanyUnited States
- Department of Biomedical Sciences, University at AlbanyAlbanyUnited States
| | - Yasu S Morita
- Molecular and Cellular Biology Graduate Program, University of MassachusettsAmherstUnited States
- Department of Microbiology, University of MassachusettsAmherstUnited States
| | - M Sloan Siegrist
- Molecular and Cellular Biology Graduate Program, University of MassachusettsAmherstUnited States
- Department of Microbiology, University of MassachusettsAmherstUnited States
| |
Collapse
|
79
|
Hou S, Mahadevegowda SH, Lu D, Zhang K, Chan-Park MB, Duan H. Metabolic Labeling Mediated Targeting and Thermal Killing of Gram-Positive Bacteria by Self-Reporting Janus Magnetic Nanoparticles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2006357. [PMID: 33325629 DOI: 10.1002/smll.202006357] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/18/2020] [Indexed: 06/12/2023]
Abstract
Nanoparticles have been widely used in detection and killing of bacteria; however, targeting bacteria is still challenging. Delicate design of nanoparticles is required for simultaneous targeting, detection, and therapeutic functions. Here the use of Au/MnFe2 O4 (Au/MFO) Janus nanoparticles to target Gram-positive bacteria via metabolic labeling is reported and realize integrated self-reporting and thermal killing of bacteria. In these nanoparticles, the Au component is functionalized with tetrazine to target trans-cyclooctene group anchored on bacterial cell wall by metabolic incorporation of d-amino acids, and the MFO part exhibits peroxidase activity, enabling self-reporting of bacteria before treatment. The spatial separation of targeting and reporting functions avoids the deterioration of catalytic activity after surface modification. Also important is that MFO facilitates magnetic separation and magnetic heating, leading to easy enrichment and magnetic thermal therapy of labeled bacteria. This method demonstrates that metabolic labeling with d-amino acids is a promising strategy to specifically target and kill Gram-positive bacteria.
Collapse
Affiliation(s)
- Shuai Hou
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Surendra H Mahadevegowda
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Derong Lu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Kaixi Zhang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Mary B Chan-Park
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Hongwei Duan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| |
Collapse
|
80
|
Singh R, Slade JA, Brockett M, Mendez D, Liechti GW, Maurelli AT. Competing Substrates for the Bifunctional Diaminopimelic Acid Epimerase/Glutamate Racemase Modulate Peptidoglycan Synthesis in Chlamydia trachomatis. Infect Immun 2020; 89:IAI.00401-20. [PMID: 33106295 PMCID: PMC7927921 DOI: 10.1128/iai.00401-20] [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: 07/07/2020] [Accepted: 10/21/2020] [Indexed: 11/20/2022] Open
Abstract
The Chlamydia trachomatis genome encodes multiple bifunctional enzymes, such as DapF, which is capable of both diaminopimelic acid (DAP) epimerase and glutamate racemase activity. Our previous work demonstrated the bifunctional activity of chlamydial DapF in vitro and in a heterologous system (Escherichia coli). In the present study, we employed a substrate competition strategy to demonstrate DapF Ct function in vivo in C. trachomatis We reasoned that, because DapF Ct utilizes a shared substrate-binding site for both racemase and epimerase activities, only one activity can occur at a time. Therefore, an excess of one substrate relative to another must determine which activity is favored. We show that the addition of excess l-glutamate or meso-DAP (mDAP) to C. trachomatis resulted in 90% reduction in bacterial titers, compared to untreated controls. Excess l-glutamate reduced in vivo synthesis of mDAP by C. trachomatis to undetectable levels, thus confirming that excess racemase substrate led to inhibition of DapF Ct DAP epimerase activity. We previously showed that expression of dapFCt in a murI (racemase) ΔdapF (epimerase) double mutant of E. coli rescues the d-glutamate auxotrophic defect. Addition of excess mDAP inhibited growth of this strain, but overexpression of dapFCt allowed the mutant to overcome growth inhibition. These results confirm that DapF Ct is the primary target of these mDAP and l-glutamate treatments. Our findings demonstrate that suppression of either the glutamate racemase or epimerase activity of DapF compromises the growth of C. trachomatis Thus, a substrate competition strategy can be a useful tool for in vivo validation of an essential bifunctional enzyme.
Collapse
Affiliation(s)
- Raghuveer Singh
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
| | - Jessica A Slade
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
| | - Mary Brockett
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Daniel Mendez
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
| | - George W Liechti
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Anthony T Maurelli
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
81
|
Rivas-Marin E, Wiegand S, Kallscheuer N, Jogler M, Peeters SH, Heuer A, Jetten MSM, Boedeker C, Rohde M, Devos DP, Jogler C. Maioricimonas rarisocia gen. nov., sp. nov., a novel planctomycete isolated from marine sediments close to Mallorca Island. Antonie Van Leeuwenhoek 2020; 113:1901-1913. [PMID: 32583192 PMCID: PMC7716917 DOI: 10.1007/s10482-020-01436-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/11/2020] [Indexed: 02/07/2023]
Abstract
Planctomycetes are ubiquitous bacteria with environmental and biotechnological relevance. Axenic cultures of planctomycetal strains are the basis to analyse their unusual biology and largely uncharacterised metabolism in more detail. Here, we describe strain Mal4T isolated from marine sediments close to Palma de Mallorca, Spain. Strain Mal4T displays common planctomycetal features, such as division by polar budding and the presence of fimbriae and crateriform structures on the cell surface. Cell growth was observed at ranges of 10-39 °C (optimum at 31 °C) and pH 6.5-9.0 (optimum at 7.5). The novel strain shows as pear-shaped cells of 2.0 ± 0.2 × 1.4 ± 0.1 µm and is one of the rare examples of orange colony-forming Planctomycetes. Its genome has a size of 7.7 Mb with a G+C content of 63.4%. Phylogenetically, we conclude that strain Mal4T (= DSM 100296T = LMG 29133T) is the type strain representing the type species of a novel genus, for which we propose the name Maioricimonas rarisocia gen. nov., sp. nov.
Collapse
Affiliation(s)
- Elena Rivas-Marin
- Centro Andaluz de Biología del Desarrollo, CSIC, Universidad Pablo de Olavide, Seville, Spain
| | - Sandra Wiegand
- Institute for Biological Interfaces 5, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | | | - Mareike Jogler
- Department of Microbial Interactions, Friedrich-Schiller University, Jena, Germany
| | - Stijn H Peeters
- Department of Microbiology, Radboud Universiteit, Nijmegen, The Netherlands
| | - Anja Heuer
- Leibniz Institute DSMZ, Brunswick, Germany
| | - Mike S M Jetten
- Department of Microbiology, Radboud Universiteit, Nijmegen, The Netherlands
| | | | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Brunswick, Germany
| | - Damien P Devos
- Centro Andaluz de Biología del Desarrollo, CSIC, Universidad Pablo de Olavide, Seville, Spain
| | - Christian Jogler
- Department of Microbiology, Radboud Universiteit, Nijmegen, The Netherlands.
- Department of Microbial Interactions, Friedrich-Schiller University, Jena, Germany.
| |
Collapse
|
82
|
Rivera SL, Espaillat A, Aditham AK, Shieh P, Muriel-Mundo C, Kim J, Cava F, Siegrist MS. Chemically Induced Cell Wall Stapling in Bacteria. Cell Chem Biol 2020; 28:213-220.e4. [PMID: 33238158 DOI: 10.1016/j.chembiol.2020.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/09/2020] [Accepted: 11/06/2020] [Indexed: 12/16/2022]
Abstract
Transpeptidation reinforces the structure of cell-wall peptidoglycan, an extracellular heteropolymer that protects bacteria from osmotic lysis. The clinical success of transpeptidase-inhibiting β-lactam antibiotics illustrates the essentiality of these cross-linkages for cell-wall integrity, but the presence of multiple, seemingly redundant transpeptidases in many species makes it challenging to determine cross-link function. Here, we present a technique to link peptide strands by chemical rather than enzymatic reaction. We employ biocompatible click chemistry to induce triazole formation between azido- and alkynyl-d-alanine residues that are metabolically installed in the peptidoglycan of Gram-positive or Gram-negative bacteria. Synthetic triazole cross-links can be visualized using azidocoumarin-d-alanine, an amino acid derivative that undergoes fluorescent enhancement upon reaction with terminal alkynes. Cell-wall stapling protects Escherichia coli from treatment with the broad-spectrum β-lactams ampicillin and carbenicillin. Chemical control of cell-wall structure in live bacteria can provide functional insights that are orthogonal to those obtained by genetics.
Collapse
Affiliation(s)
- Sylvia L Rivera
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - Akbar Espaillat
- Laboratory for Molecular Infection Medicine, Department of Molecular Biology, Umeå University, Umeå 90187, Sweden
| | - Arjun K Aditham
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Stanford ChEM-H (Chemistry, Engineering, and Medicine for Human Health), Stanford University, Stanford, CA 94305, USA
| | - Peyton Shieh
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Chris Muriel-Mundo
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - Justin Kim
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine, Department of Molecular Biology, Umeå University, Umeå 90187, Sweden.
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; Molecular and Cellular Biology Program, University of Massachusetts, Amherst, MA 01003, USA.
| |
Collapse
|
83
|
Hira J, Uddin MJ, Haugland MM, Lentz CS. From Differential Stains to Next Generation Physiology: Chemical Probes to Visualize Bacterial Cell Structure and Physiology. Molecules 2020; 25:E4949. [PMID: 33114655 PMCID: PMC7663024 DOI: 10.3390/molecules25214949] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 12/16/2022] Open
Abstract
Chemical probes have been instrumental in microbiology since its birth as a discipline in the 19th century when chemical dyes were used to visualize structural features of bacterial cells for the first time. In this review article we will illustrate the evolving design of chemical probes in modern chemical biology and their diverse applications in bacterial imaging and phenotypic analysis. We will introduce and discuss a variety of different probe types including fluorogenic substrates and activity-based probes that visualize metabolic and specific enzyme activities, metabolic labeling strategies to visualize structural features of bacterial cells, antibiotic-based probes as well as fluorescent conjugates to probe biomolecular uptake pathways.
Collapse
Affiliation(s)
- Jonathan Hira
- Research Group for Host-Microbe Interactions, Department of Medical Biology and Centre for New Antibacterial Strategies (CANS), UiT—The Arctic University of Norway, 9019 Tromsø, Norway; (J.H.); (M.J.U.)
| | - Md. Jalal Uddin
- Research Group for Host-Microbe Interactions, Department of Medical Biology and Centre for New Antibacterial Strategies (CANS), UiT—The Arctic University of Norway, 9019 Tromsø, Norway; (J.H.); (M.J.U.)
| | - Marius M. Haugland
- Department of Chemistry and Centre for New Antibacterial Strategies (CANS), UiT—The Arctic University of Norway, 9019 Tromsø, Norway;
| | - Christian S. Lentz
- Research Group for Host-Microbe Interactions, Department of Medical Biology and Centre for New Antibacterial Strategies (CANS), UiT—The Arctic University of Norway, 9019 Tromsø, Norway; (J.H.); (M.J.U.)
| |
Collapse
|
84
|
Super-Resolution Fluorescence Microscopy Reveals Clustering Behaviour of Chlamydia pneumoniae's Major Outer Membrane Protein. BIOLOGY 2020; 9:biology9100344. [PMID: 33092039 PMCID: PMC7589890 DOI: 10.3390/biology9100344] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/16/2020] [Accepted: 10/16/2020] [Indexed: 12/20/2022]
Abstract
Chlamydia pneumoniae is a Gram-negative bacterium responsible for a number of human respiratory diseases and linked to some chronic inflammatory diseases. The major outer membrane protein (MOMP) of Chlamydia is a conserved immunologically dominant protein located in the outer membrane, which, together with its surface exposure and abundance, has led to MOMP being the main focus for vaccine and antimicrobial studies in recent decades. MOMP has a major role in the chlamydial outer membrane complex through the formation of intermolecular disulphide bonds, although the exact interactions formed are currently unknown. Here, it is proposed that due to the large number of cysteines available for disulphide bonding, interactions occur between cysteine-rich pockets as opposed to individual residues. Such pockets were identified using a MOMP homology model with a supporting low-resolution (~4 Å) crystal structure. The localisation of MOMP in the E. coli membrane was assessed using direct stochastic optical reconstruction microscopy (dSTORM), which showed a decrease in membrane clustering with cysteine-rich regions containing two mutations. These results indicate that disulphide bond formation was not disrupted by single mutants located in the cysteine-dense regions and was instead compensated by neighbouring cysteines within the pocket in support of this cysteine-rich pocket hypothesis.
Collapse
|
85
|
Abstract
Chlamydia trachomatis is an obligate intracellular bacterium that can cause trachoma, cervicitis, urethritis, salpingitis, and pelvic inflammatory disease. To establish infection in host cells, Chlamydia must complete a multiple-cell-type developmental cycle. The developmental cycle consists of specialized cells, the EB cell, which mediates infection of new host cells, and the RB cell, which replicates and eventually produces more EB cells to mediate the next round of infection. By developing and testing mathematical models to discriminate between two competing hypotheses for the nature of the signal controlling RB-to-EB cell type switching, we demonstrate that RB-to-EB development follows a cell-autonomous program that does not respond to environmental cues. Additionally, we show that RB-to-EB development is a function of chlamydial growth and division. This study serves to further our understanding of the chlamydial developmental cycle that is central to the bacterium’s pathogenesis. The obligate intracellular bacterial pathogen Chlamydia trachomatis is reliant on a developmental cycle consisting of two cell forms, termed the elementary body (EB) and the reticulate body (RB). The EB is infectious and utilizes a type III secretion system and preformed effector proteins during invasion, but it does not replicate. The RB replicates in the host cell but is noninfectious. This developmental cycle is central to chlamydial pathogenesis. In this study, we developed mathematical models of the developmental cycle that account for potential factors influencing RB-to-EB cell type switching during infection. Our models predicted that two categories of regulatory signals for RB-to-EB development could be differentiated experimentally, an “intrinsic” cell-autonomous program inherent to each RB and an “extrinsic” environmental signal to which RBs respond. To experimentally differentiate between mechanisms, we tracked the expression of C. trachomatis development-specific promoters in individual inclusions using fluorescent reporters and live-cell imaging. These experiments indicated that EB production was not influenced by increased multiplicity of infection or by superinfection, suggesting the cycle follows an intrinsic program that is not directly controlled by environmental factors. Additionally, live-cell imaging revealed that EB development is a multistep process linked to RB growth rate and cell division. The formation of EBs followed a progression with expression from the euo and ihtA promoters evident in RBs, while expression from the promoter for hctA was apparent in early EBs/IBs. Finally, expression from the promoters for the true late genes, hctB, scc2, and tarp, was evident in the maturing EB. IMPORTANCEChlamydia trachomatis is an obligate intracellular bacterium that can cause trachoma, cervicitis, urethritis, salpingitis, and pelvic inflammatory disease. To establish infection in host cells, Chlamydia must complete a multiple-cell-type developmental cycle. The developmental cycle consists of specialized cells, the EB cell, which mediates infection of new host cells, and the RB cell, which replicates and eventually produces more EB cells to mediate the next round of infection. By developing and testing mathematical models to discriminate between two competing hypotheses for the nature of the signal controlling RB-to-EB cell type switching, we demonstrate that RB-to-EB development follows a cell-autonomous program that does not respond to environmental cues. Additionally, we show that RB-to-EB development is a function of chlamydial growth and division. This study serves to further our understanding of the chlamydial developmental cycle that is central to the bacterium’s pathogenesis.
Collapse
|
86
|
Mahajan M, Seeger C, Yee B, Andersson SGE. Evolutionary Remodeling of the Cell Envelope in Bacteria of the Planctomycetes Phylum. Genome Biol Evol 2020; 12:1528-1548. [PMID: 32761170 DOI: 10.1093/gbe/evaa159] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2020] [Indexed: 01/09/2023] Open
Abstract
Bacteria of the Planctomycetes phylum have many unique cellular features, such as extensive membrane invaginations and the ability to import macromolecules. These features raise intriguing questions about the composition of their cell envelopes. In this study, we have used microscopy, phylogenomics, and proteomics to examine the composition and evolution of cell envelope proteins in Tuwongella immobilis and other members of the Planctomycetes. Cryo-electron tomography data indicated a distance of 45 nm between the inner and outer membranes in T. immobilis. Consistent with the wide periplasmic space, our bioinformatics studies showed that the periplasmic segments of outer-membrane proteins in type II secretion systems are extended in bacteria of the order Planctomycetales. Homologs of two highly abundant cysteine-rich cell wall proteins in T. immobilis were identified in all members of the Planctomycetales, whereas genes for peptidoglycan biosynthesis and cell elongation have been lost in many members of this bacterial group. The cell wall proteins contain multiple copies of the YTV motif, which is the only domain that is conserved and unique to the Planctomycetales. Earlier diverging taxa in the Planctomycetes phylum contain genes for peptidoglycan biosynthesis but no homologs to the YTV cell wall proteins. The major remodeling of the cell envelope in the ancestor of the Planctomycetales coincided with the emergence of budding and other unique cellular phenotypes. The results have implications for hypotheses about the process whereby complex cellular features evolve in bacteria.
Collapse
Affiliation(s)
- Mayank Mahajan
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Sweden
| | - Christian Seeger
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Sweden
| | - Benjamin Yee
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Sweden
| | - Siv G E Andersson
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Centre, Uppsala University, Sweden
| |
Collapse
|
87
|
Abstract
Chlamydia is an obligate intracellular bacterial pathogen that has significantly reduced its genome size in adapting to its intracellular niche. Among the genes that Chlamydia has eliminated is ftsZ, encoding the central organizer of cell division that directs cell wall synthesis in the division septum. These Gram-negative pathogens have cell envelopes that lack peptidoglycan (PG), yet they use PG for cell division purposes. Recent research into chlamydial PG synthesis, components of the chlamydial divisome, and the mechanism of chlamydial division have significantly advanced our understanding of these processes in a unique and important pathogen. For example, it has been definitively confirmed that chlamydiae synthesize a canonical PG structure during cell division. Various studies have suggested and provided evidence that Chlamydia uses MreB to substitute for FtsZ in organizing and coordinating the divisome during division, components of which have been identified and characterized. Finally, as opposed to using an FtsZ-dependent binary fission process, Chlamydia employs an MreB-dependent polarized budding process to divide. A brief historical context for these key advances is presented along with a discussion of the current state of knowledge of chlamydial cell division.
Collapse
|
88
|
Rajeeve K, Vollmuth N, Janaki-Raman S, Wulff TF, Baluapuri A, Dejure FR, Huber C, Fink J, Schmalhofer M, Schmitz W, Sivadasan R, Eilers M, Wolf E, Eisenreich W, Schulze A, Seibel J, Rudel T. Reprogramming of host glutamine metabolism during Chlamydia trachomatis infection and its key role in peptidoglycan synthesis. Nat Microbiol 2020; 5:1390-1402. [PMID: 32747796 DOI: 10.1038/s41564-020-0762-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 06/26/2020] [Indexed: 12/31/2022]
Abstract
Obligate intracellular bacteria such as Chlamydia trachomatis undergo a complex developmental cycle between infectious, non-replicative elementary-body and non-infectious, replicative reticulate-body forms. Elementary bodies transform to reticulate bodies shortly after entering a host cell, a crucial process in infection, initiating chlamydial replication. As Chlamydia fail to replicate outside the host cell, it is unknown how the replicative part of the developmental cycle is initiated. Here we show, using a cell-free approach in axenic media, that the uptake of glutamine by the bacteria is crucial for peptidoglycan synthesis, which has a role in Chlamydia replication. The increased requirement for glutamine in infected cells is satisfied by reprogramming the glutamine metabolism in a c-Myc-dependent manner. Glutamine is effectively taken up by the glutamine transporter SLC1A5 and metabolized via glutaminase. Interference with this metabolic reprogramming limits the growth of Chlamydia. Intriguingly, Chlamydia failed to produce progeny in SLC1A5-knockout organoids and mice. Thus, we report on the central role of glutamine for the development of an obligate intracellular pathogenic bacterium and the reprogramming of host glutamine metabolism, which may provide a basis for innovative anti-infection strategies.
Collapse
Affiliation(s)
- Karthika Rajeeve
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany. .,Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
| | - Nadine Vollmuth
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Sudha Janaki-Raman
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Thomas F Wulff
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Apoorva Baluapuri
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Francesca R Dejure
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany.,BioMed X Institute, Heidelberg, Germany
| | - Claudia Huber
- Chair of Biochemistry, Technical University of Munich, Garching, Germany
| | - Julian Fink
- Institute of Organic Chemistry, University of Würzburg, Würzburg, Germany
| | | | - Werner Schmitz
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Rajeeve Sivadasan
- RNA Biology and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Martin Eilers
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Elmar Wolf
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | | | - Almut Schulze
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, Würzburg, Germany.,Division of Tumour Metabolism and Microenvironment, German Cancer Research Center, Heidelberg, Germany
| | - Jürgen Seibel
- Institute of Organic Chemistry, University of Würzburg, Würzburg, Germany
| | - Thomas Rudel
- Department of Microbiology, Biocenter, University of Würzburg, Würzburg, Germany. .,Helmholtz Institute for RNA-based Infection Research (HIRI), Würzburg, Germany.
| |
Collapse
|
89
|
Fluorescent probes for investigating peptidoglycan biosynthesis in mycobacteria. Curr Opin Chem Biol 2020; 57:50-57. [DOI: 10.1016/j.cbpa.2020.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/31/2020] [Accepted: 04/08/2020] [Indexed: 02/02/2023]
|
90
|
Penicillin-binding proteins regulate multiple steps in the polarized cell division process of Chlamydia. Sci Rep 2020; 10:12588. [PMID: 32724139 PMCID: PMC7387471 DOI: 10.1038/s41598-020-69397-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 07/08/2020] [Indexed: 12/26/2022] Open
Abstract
Chlamydia trachomatis serovar L2 and Chlamydia muridarum, which do not express FtsZ, undergo polarized cell division. During division, peptidoglycan assembles at the pole of dividing Chlamydia trachomatis cells where daughter cell formation occurs, and peptidoglycan regulates at least two distinct steps in the polarized division of Chlamydia trachomatis and Chlamydia muridarum. Cells treated with inhibitors that prevent peptidoglycan synthesis or peptidoglycan crosslinking by penicillin-binding protein 2 (PBP2) are unable to initiate polarized division, while cells treated with inhibitors that prevent peptidoglycan crosslinking by penicillin-binding protein 3 (PBP3/FtsI) initiate polarized division, but the process arrests at an early stage of daughter cell growth. Consistent with their distinct roles in polarized division, peptidoglycan organization is different in cells treated with PBP2 and PBP3-specific inhibitors. Our analyses indicate that the sequential action of PBP2 and PBP3 drives changes in peptidoglycan organization that are essential for the polarized division of these obligate intracellular bacteria. Furthermore, the roles we have characterized for PBP2 and PBP3 in regulating specific steps in chlamydial cell division have not been described in other bacteria.
Collapse
|
91
|
Kuru E, Määttälä RM, Noguera K, Stork DA, Narasimhan K, Rittichier J, Wiegand D, Church GM. Release Factor Inhibiting Antimicrobial Peptides Improve Nonstandard Amino Acid Incorporation in Wild-type Bacterial Cells. ACS Chem Biol 2020; 15:1852-1861. [PMID: 32603088 DOI: 10.1021/acschembio.0c00055] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We report a tunable chemical genetics approach for enhancing genetic code expansion in different wild-type bacterial strains that employ apidaecin-like, antimicrobial peptides observed to temporarily sequester and thereby inhibit Release Factor 1 (RF1). In a concentration-dependent matter, these peptides granted a conditional lambda phage resistance to a recoded Escherichia coli strain with nonessential RF1 activity and promoted multisite nonstandard amino acid (nsAA) incorporation at in-frame amber stop codons in vivo and in vitro. When exogenously added, the peptides stimulated specific nsAA incorporation in a variety of sensitive, wild-type (RF1+) strains, including Agrobacterium tumefaciens, a species in which nsAA incorporation has not been previously reported. Improvement in nsAA incorporation was typically 2-15-fold in E. coli BL21, MG1655, and DH10B strains and A. tumefaciens with the >20-fold improvement observed in probiotic E. coli Nissle 1917. In-cell expression of these peptides promoted multisite nsAA incorporation in transcripts with up to 6 amber codons, with a >35-fold increase in BL21 showing moderate toxicity. Leveraging this RF1 sensitivity allowed multiplexed partial recoding of MG1655 and DH10B that rapidly resulted in resistant strains that showed an additional approximately twofold boost to nsAA incorporation independent of the peptide. Finally, in-cell expression of an apidaecin-like peptide library allowed the discovery of new peptide variants with reduced toxicity that still improved multisite nsAA incorporation >25-fold. In parallel to genetic reprogramming efforts, these new approaches can facilitate genetic code expansion technologies in a variety of wild-type bacterial strains.
Collapse
Affiliation(s)
- Erkin Kuru
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss Institute for Biologically Inspired Engineering, Boston, Massachusetts 02115, United States
| | - Rosa-Maria Määttälä
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
- School of Arts and Sciences, MCPHS University, Boston, Massachusetts 02115, United States
| | - Karen Noguera
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Devon A. Stork
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Kamesh Narasimhan
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Jonathan Rittichier
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss Institute for Biologically Inspired Engineering, Boston, Massachusetts 02115, United States
| | - Daniel Wiegand
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss Institute for Biologically Inspired Engineering, Boston, Massachusetts 02115, United States
| | - George M. Church
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, United States
- Wyss Institute for Biologically Inspired Engineering, Boston, Massachusetts 02115, United States
| |
Collapse
|
92
|
DeMeester KE, Liang H, Zhou J, Wodzanowski KA, Prather BL, Santiago CC, Grimes CL. Metabolic Incorporation of N-Acetyl Muramic Acid Probes into Bacterial Peptidoglycan. ACTA ACUST UNITED AC 2020; 11:e74. [PMID: 31763799 DOI: 10.1002/cpch.74] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bacterial cells utilize small carbohydrate building blocks to construct peptidoglycan (PG), a highly conserved mesh-like polymer that serves as a protective coat for the cell. PG production has long been a target for antibiotics, and its breakdown is a source for human immune recognition. A key component of bacterial PG, N-acetyl muramic acid (NAM), is a vital element in many synthetically derived immunostimulatory compounds. However, the exact molecular details of these structures and how they are generated remain unknown due to a lack of chemical probes surrounding the NAM core. A robust synthetic strategy to generate bioorthogonally tagged NAM carbohydrate units is implemented. These molecules serve as precursors for PG biosynthesis and recycling. Escherichia coli cells are metabolically engineered to incorporate the bioorthogonal NAM probes into their PG network. The probes are subsequently modified using copper-catalyzed azide-alkyne cycloaddition to install fluorophores directly into the bacterial PG, as confirmed by super-resolution microscopy and high-resolution mass spectrometry. Here, synthetic notes for key elements of this process to generate the sugar probes as well as streamlined user-friendly metabolic labeling strategies for both microbiology and immunological applications are described. © 2019 by John Wiley & Sons, Inc. Basic Protocol 1: Synthesis of peracetylated 2-azido glucosamine Basic Protocol 2: Synthesis of 2-azido and 2-alkyne NAM Basic Protocol 3: Synthesis of 3-azido NAM methyl ester Basic Protocol 4: Incorporation of NAM probes into bacterial peptidoglycan Basic Protocol 5: Confirmation of bacterial cell wall remodeling by mass spectrometry.
Collapse
Affiliation(s)
- Kristen E DeMeester
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware
| | - Hai Liang
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware.,Cutaneous Microbiome and Inflammation Section, Dermatology Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland
| | - Junhui Zhou
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware
| | | | - Benjamin L Prather
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware
| | - Cintia C Santiago
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware.,Center for the Study of Organic Compounds, CEDECOR-UNLP-CIC, Department of Chemistry, Faculty of Exact Sciences, National University of La Plata, Buenos Aires, Argentina
| | - Catherine L Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware.,Department of Biological Sciences, University of Delaware, Newark, Delaware
| |
Collapse
|
93
|
Qiao Y, Hayashi H, Chong Teo S. Chemical Toolbox to Decode the Microbiota Lexicon. Chem Asian J 2020; 15:2117-2128. [PMID: 32558250 DOI: 10.1002/asia.202000541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/14/2020] [Indexed: 12/15/2022]
Abstract
The human microbiota deploys a diverse range of molecules and metabolites to engage in chemical communications with the host, mediating fundamental aspects of host health. Studies of the structures and activities of bioactive molecules produced by the microbiota are imperative to address their implications in microbiota associated diseases in human. By drawing experiences from different research fields, chemists and chemical biologists, who are experts in dealing with chemical molecules, are uniquely positioned to contribute to the emerging knowledge of human microbiota. In this minireview, we discuss the current chemical tools and methods that are pertinent to the discovery of microbiota molecules and metabolites, characterizations of their protein targets, as well as evaluations of their biodistributions in hosts. These are key aspects in understanding the chemical underpinnings of the microbiota-host interactions that would enable future development of diagnostics and therapeutics targeting the human microbiota.
Collapse
Affiliation(s)
- Yuan Qiao
- School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), 21 Nanyang Link, CBC 04-22, Singapore, 637371, Singapore
| | - Hirohito Hayashi
- School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), 21 Nanyang Link, CBC 04-22, Singapore, 637371, Singapore
| | - Seng Chong Teo
- School of Physical and Mathematical Sciences (SPMS), Nanyang Technological University (NTU), 21 Nanyang Link, CBC 04-22, Singapore, 637371, Singapore
| |
Collapse
|
94
|
Weatherhead AW, Crowther JM, Horne CR, Meng Y, Coombes D, Currie MJ, Watkin SAJ, Adams LE, Parthasarathy A, Dobson RCJ, Hudson AO. Structure-Function Studies of the Antibiotic Target l,l-Diaminopimelate Aminotransferase from Verrucomicrobium spinosum Reveal an Unusual Oligomeric Structure. Biochemistry 2020; 59:2274-2288. [PMID: 32478518 DOI: 10.1021/acs.biochem.0c00185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
While humans lack the biosynthetic pathways for meso-diaminopimelate and l-lysine, they are essential for bacterial survival and are therefore attractive targets for antibiotics. It was recently discovered that members of the Chlamydia family utilize a rare aminotransferase route of the l-lysine biosynthetic pathway, thus offering a new enzymatic drug target. Here we characterize diaminopimelate aminotransferase from Verrucomicrobium spinosum (VsDapL), a nonpathogenic model bacterium for Chlamydia trachomatis. Complementation experiments verify that the V. spinosum dapL gene encodes a bona fide diaminopimelate aminotransferase, because the gene rescues an Escherichia coli strain that is auxotrophic for meso-diaminopimelate. Kinetic studies show that VsDapL follows a Michaelis-Menten mechanism, with a KMapp of 4.0 mM toward its substrate l,l-diaminopimelate. The kcat (0.46 s-1) and the kcat/KM (115 s-1 M-1) are somewhat lower than values for other diaminopimelate aminotransferases. Moreover, whereas other studied DapL orthologs are dimeric, sedimentation velocity experiments demonstrate that VsDapL exists in a monomer-dimer self-association, with a KD2-1 of 7.4 μM. The 2.25 Å resolution crystal structure presents the canonical dimer of chalice-shaped monomers, and small-angle X-ray scattering experiments confirm the dimer in solution. Sequence and structural alignments reveal that active site residues important for activity are conserved in VsDapL, despite the lower activity compared to those of other DapL homologues. Although the dimer interface buries 18% of the total surface area, several loops that contribute to the interface and active site, notably the L1, L2, and L5 loops, are highly mobile, perhaps explaining the unstable dimer and lower catalytic activity. Our kinetic, biophysical, and structural characterization can be used to inform the development of antibiotics.
Collapse
Affiliation(s)
- Anthony W Weatherhead
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Jennifer M Crowther
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Christopher R Horne
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Yanxiang Meng
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - David Coombes
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Michael J Currie
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Serena A J Watkin
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand
| | - Lily E Adams
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, New York 14623-5603, United States
| | - Anutthaman Parthasarathy
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, New York 14623-5603, United States
| | - Renwick C J Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch 8140, New Zealand.,Bio21 Molecular Science and Biotechnology Institute, Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - André O Hudson
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, New York 14623-5603, United States
| |
Collapse
|
95
|
Fluorescent amino acids as versatile building blocks for chemical biology. Nat Rev Chem 2020; 4:275-290. [PMID: 37127957 DOI: 10.1038/s41570-020-0186-z] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2020] [Indexed: 12/13/2022]
Abstract
Fluorophores have transformed the way we study biological systems, enabling non-invasive studies in cells and intact organisms, which increase our understanding of complex processes at the molecular level. Fluorescent amino acids have become an essential chemical tool because they can be used to construct fluorescent macromolecules, such as peptides and proteins, without disrupting their native biomolecular properties. Fluorescent and fluorogenic amino acids with unique photophysical properties have been designed for tracking protein-protein interactions in situ or imaging nanoscopic events in real time with high spatial resolution. In this Review, we discuss advances in the design and synthesis of fluorescent amino acids and how they have contributed to the field of chemical biology in the past 10 years. Important areas of research that we review include novel methodologies to synthesize building blocks with tunable spectral properties, their integration into peptide and protein scaffolds using site-specific genetic encoding and bioorthogonal approaches, and their application to design novel artificial proteins, as well as to investigate biological processes in cells by means of optical imaging.
Collapse
|
96
|
Hong S, Zheng DW, Zhang QL, Deng WW, Song WF, Cheng SX, Sun ZJ, Zhang XZ. An RGB-emitting molecular cocktail for the detection of bacterial fingerprints. Chem Sci 2020; 11:4403-4409. [PMID: 33209242 PMCID: PMC7643548 DOI: 10.1039/d0sc01704c] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 04/01/2020] [Indexed: 01/27/2023] Open
Abstract
Accumulating evidence indicates that colonized microbes play a crucial role in regulating health and disease in the human body. Detecting microbes should be essential for understanding the relationship between microbes and diseases, as well as increasing our ability to detect diseases. Here, a combined metabolic labeling strategy was developed to identify different bacterial species and microbiota by the use of three different fluorescent metabolite derivatives emitting red, green, and blue (RGB) fluorescence. Upon co-incubation with microbes, these fluorescent metabolite derivatives are incorporated into bacteria, generating unique true-color fingerprints for different bacterial species and different microbiota. A portable spectrometer was also fabricated to automate the colorimetric analysis in combination with a smartphone to conveniently identify different bacterial species and microbiota. Herein, the effectiveness of this system was demonstrated by the identification of certain bacterial species and microbiota in mice with different diseases, such as skin infections and bacteremia. By analyzing the microbiota fingerprints of saliva samples from clinical patients and healthy people, this system was proved to precisely distinguish oral squamous cell carcinoma (OSCC, n = 29) samples from precancerous (n = 10) and healthy (n = 5) samples.
Collapse
Affiliation(s)
- Sheng Hong
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| | - Di-Wei Zheng
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| | - Qiu-Ling Zhang
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| | - Wei-Wei Deng
- Department of Oral Maxillofacial Head Neck Oncology , School and Hospital of Stomatology , Wuhan University , Wuhan 430072 , P. R. China
| | - Wen-Fang Song
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| | - Si-Xue Cheng
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| | - Zhi-Jun Sun
- Department of Oral Maxillofacial Head Neck Oncology , School and Hospital of Stomatology , Wuhan University , Wuhan 430072 , P. R. China
| | - Xian-Zheng Zhang
- Key Laboratory of Biomedical Polymers of Ministry of Education , Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China .
| |
Collapse
|
97
|
Chlamydia trachomatis Oligopeptide Transporter Performs Dual Functions of Oligopeptide Transport and Peptidoglycan Recycling. Infect Immun 2020; 88:IAI.00086-20. [PMID: 32094256 DOI: 10.1128/iai.00086-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 02/18/2020] [Indexed: 12/20/2022] Open
Abstract
Peptidoglycan, the sugar-amino acid polymer that composes the bacterial cell wall, requires a significant expenditure of energy to synthesize and is highly immunogenic. To minimize the loss of an energetically expensive metabolite and avoid host detection, bacteria often recycle their peptidoglycan, transporting its components back into the cytoplasm, where they can be used for subsequent rounds of new synthesis. The peptidoglycan-recycling substrate binding protein (SBP) MppA, which is responsible for recycling peptidoglycan fragments in Escherichia coli, has not been annotated for most intracellular pathogens. One such pathogen, Chlamydia trachomatis, has a limited capacity to synthesize amino acids de novo and therefore must obtain oligopeptides from its host cell for growth. Bioinformatics analysis suggests that the putative C. trachomatis oligopeptide transporter OppABCDF (OppABCDF Ct ) encodes multiple SBPs (OppA1 Ct , OppA2 Ct , and OppA3 Ct ). Intracellular pathogens often encode multiple SBPs, while only one, OppA, is encoded in the E. coli opp operon. We hypothesized that the putative OppABCDF transporter of C. trachomatis functions in both oligopeptide transport and peptidoglycan recycling. We coexpressed the putative SBP genes (oppA1Ct , oppA2Ct , oppA3Ct ) along with oppBCDFCt in an E. coli mutant lacking the Opp transporter and determined that all three chlamydial OppA subunits supported oligopeptide transport. We also demonstrated the in vivo functionality of the chlamydial Opp transporter in C. trachomatis Importantly, we found that one chlamydial SBP, OppA3 Ct , possessed dual substrate recognition properties and is capable of transporting peptidoglycan fragments (tri-diaminopimelic acid) in E. coli and in C. trachomatis These findings suggest that Chlamydia evolved an oligopeptide transporter to facilitate the acquisition of oligopeptides for growth while simultaneously reducing the accumulation of immunostimulatory peptidoglycan fragments in the host cell cytosol. The latter property reflects bacterial pathoadaptation that dampens the host innate immune response to Chlamydia infection.
Collapse
|
98
|
Critical Role for the Extended N Terminus of Chlamydial MreB in Directing Its Membrane Association and Potential Interaction with Divisome Proteins. J Bacteriol 2020; 202:JB.00034-20. [PMID: 32041796 DOI: 10.1128/jb.00034-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 02/06/2020] [Indexed: 12/17/2022] Open
Abstract
Chlamydiae lack the conserved central coordinator protein of cell division FtsZ, a tubulin-like homolog. Current evidence indicates that Chlamydia uses the actin-like homolog, MreB, to substitute for the role of FtsZ in a polarized division mechanism. Interestingly, we observed MreB as a ring at the septum in dividing cells of Chlamydia We hypothesize that MreB, to substitute for FtsZ in Chlamydia, must possess unique properties compared to canonical MreB orthologs. Sequence differences between chlamydial MreB and orthologs in other bacteria revealed that chlamydial MreB possesses an extended N-terminal region, harboring predicted amphipathicity, as well as the conserved amphipathic helix found in other bacterial MreBs. The conserved amphipathic helix-directed green fluorescent protein (GFP) to label the membrane uniformly in Escherichia coli but the extended N-terminal region did not. However, the extended N-terminal region together with the conserved amphipathic region directed GFP to restrict the membrane label to the cell poles. In Chlamydia, the extended N-terminal region was sufficient to direct GFP to the membrane, and this localization was independent of an association with endogenous MreB. Importantly, mutating the extended N-terminal region to reduce its amphipathicity resulted in the accumulation of GFP in the cytosol of the chlamydiae and not in the membrane. The N-terminal domain of MreB was not required for homotypic interactions but was necessary for interactions with cell division components RodZ and FtsK. Our data provide mechanistic support for chlamydial MreB to serve as a substitute for FtsZ by forming a ringlike structure at the site of polarized division.IMPORTANCE Chlamydia trachomatis is an obligate intracellular pathogen, causing sexually transmitted diseases and trachoma. The study of chlamydial physiology is important for developing novel therapeutic strategies for these diseases. Chlamydiae divide by a unique MreB-dependent polarized cell division process. In this study, we investigated unique properties of chlamydial MreB and observed that chlamydial species harbor an extended N-terminal region possessing amphipathicity. MreB formed a ring at the septum, like FtsZ in Escherichia coli, and its localization was dependent upon the amphipathic nature of its extended N terminus. Furthermore, this region is crucial for the interaction of MreB with cell division proteins. Given these results, chlamydial MreB likely functions at the septum as a scaffold for divisome proteins to regulate cell division in this organism.
Collapse
|
99
|
The evolution of spherical cell shape; progress and perspective. Biochem Soc Trans 2020; 47:1621-1634. [PMID: 31829405 PMCID: PMC6925525 DOI: 10.1042/bst20180634] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/06/2019] [Accepted: 11/11/2019] [Indexed: 01/29/2023]
Abstract
Bacterial cell shape is a key trait governing the extracellular and intracellular factors of bacterial life. Rod-like cell shape appears to be original which implies that the cell wall, division, and rod-like shape came together in ancient bacteria and that the myriad of shapes observed in extant bacteria have evolved from this ancestral shape. In order to understand its evolution, we must first understand how this trait is actively maintained through the construction and maintenance of the peptidoglycan cell wall. The proteins that are primarily responsible for cell shape are therefore the elements of the bacterial cytoskeleton, principally FtsZ, MreB, and the penicillin-binding proteins. MreB is particularly relevant in the transition between rod-like and spherical cell shape as it is often (but not always) lost early in the process. Here we will highlight what is known of this particular transition in cell shape and how it affects fitness before giving a brief perspective on what will be required in order to progress the field of cell shape evolution from a purely mechanistic discipline to one that has the perspective to both propose and to test reasonable hypotheses regarding the ecological drivers of cell shape change.
Collapse
|
100
|
Gitsels A, Van Lent S, Sanders N, Vanrompay D. Chlamydia: what is on the outside does matter. Crit Rev Microbiol 2020; 46:100-119. [PMID: 32093536 DOI: 10.1080/1040841x.2020.1730300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This review summarises major highlights on the structural biology of the chlamydial envelope. Chlamydiae are obligate intracellular bacteria, characterised by a unique biphasic developmental cycle. Depending on the stage of their lifecycle, they appear in the form of elementary or reticulate bodies. Since these particles have distinctive functions, it is not surprising that their envelope differs in lipid as well as in protein content. Vice versa, by identifying surface proteins, specific characteristics of the particles such as rigidity or immunogenicity may be deduced. Detailed information on the bacterial membranes will increase our understanding on the host-pathogen interactions chlamydiae employ to survive and grow and might lead to new strategies to battle chlamydial infections.
Collapse
Affiliation(s)
- Arlieke Gitsels
- Laboratory of Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Sarah Van Lent
- Laboratory of Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Niek Sanders
- Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Daisy Vanrompay
- Laboratory of Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| |
Collapse
|