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Sivaramalingam SS, Jothivel D, Govindarajan DK, Kadirvelu L, Sivaramakrishnan M, Chithiraiselvan DD, Kandaswamy K. Structural and functional insights of sortases and their interactions with antivirulence compounds. Curr Res Struct Biol 2024; 8:100152. [PMID: 38989133 PMCID: PMC11231552 DOI: 10.1016/j.crstbi.2024.100152] [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] [Received: 12/31/2023] [Revised: 05/18/2024] [Accepted: 06/11/2024] [Indexed: 07/12/2024] Open
Abstract
Sortase proteins play a crucial role as integral membrane proteins in anchoring bacterial surface proteins by recognizing them through a Cell-Wall Sorting (CWS) motif and cleaving them at specific sites before initiating pilus assembly. Both sortases and their substrate proteins are major virulence factors in numerous Gram-positive pathogens, making them attractive targets for antimicrobial intervention. Recognizing the significance of virulence proteins, a comprehensive exploration of their structural and functional characteristics is essential to enhance our understanding of pilus assembly in diverse Gram-positive bacteria. Therefore, this review article discusses the structural features of different classes of sortases and pilin proteins, primarily serving as substrates for sortase-assembled pili. Moreover, it thoroughly examines the molecular-level interactions between sortases and their inhibitors, providing insights from both structural and functional perspectives. In essence, this review article will provide a contemporary and complete understanding of both sortase pathways and various strategies to target them effectively to counteract the virulence.
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Affiliation(s)
- Sowmiya Sri Sivaramalingam
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Deepsikha Jothivel
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Deenadayalan Karaiyagowder Govindarajan
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - Lohita Kadirvelu
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Muthusaravanan Sivaramakrishnan
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
- Department of Biotechnology, Mepco Schlenk Engineering College, Tamil Nadu, India
| | - Dhivia Dharshika Chithiraiselvan
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Kumaravel Kandaswamy
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
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Barco RA, Merino N, Lam B, Budnik B, Kaplan M, Wu F, Amend JP, Nealson KH, Emerson D. Comparative proteomics of a versatile, marine, iron-oxidizing chemolithoautotroph. Environ Microbiol 2024; 26:e16632. [PMID: 38861374 DOI: 10.1111/1462-2920.16632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 04/20/2024] [Indexed: 06/13/2024]
Abstract
This study conducted a comparative proteomic analysis to identify potential genetic markers for the biological function of chemolithoautotrophic iron oxidation in the marine bacterium Ghiorsea bivora. To date, this is the only characterized species in the class Zetaproteobacteria that is not an obligate iron-oxidizer, providing a unique opportunity to investigate differential protein expression to identify key genes involved in iron-oxidation at circumneutral pH. Over 1000 proteins were identified under both iron- and hydrogen-oxidizing conditions, with differentially expressed proteins found in both treatments. Notably, a gene cluster upregulated during iron oxidation was identified. This cluster contains genes encoding for cytochromes that share sequence similarity with the known iron-oxidase, Cyc2. Interestingly, these cytochromes, conserved in both Bacteria and Archaea, do not exhibit the typical β-barrel structure of Cyc2. This cluster potentially encodes a biological nanowire-like transmembrane complex containing multiple redox proteins spanning the inner membrane, periplasm, outer membrane, and extracellular space. The upregulation of key genes associated with this complex during iron-oxidizing conditions was confirmed by quantitative reverse transcription-PCR. These findings were further supported by electromicrobiological methods, which demonstrated negative current production by G. bivora in a three-electrode system poised at a cathodic potential. This research provides significant insights into the biological function of chemolithoautotrophic iron oxidation.
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Affiliation(s)
- Roman A Barco
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
- Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine, USA
| | - N Merino
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Lawrence Livermore National Lab, Biosciences and Biotechnology Division, Livermore, California, USA
| | - B Lam
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - B Budnik
- Mass Spectrometry and Proteomics Resource Laboratory, Harvard University, Cambridge, Massachusetts, USA
| | - M Kaplan
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - F Wu
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, Zhejiang, China
| | - J P Amend
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - K H Nealson
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - D Emerson
- Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine, USA
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3
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de Sandozequi A, Martínez‐Anaya C. Bacterial surface-exposed lipoproteins and sortase-mediated anchored cell surface proteins in plant infection. Microbiologyopen 2023; 12:e1382. [PMID: 37877658 PMCID: PMC10501053 DOI: 10.1002/mbo3.1382] [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: 04/07/2023] [Revised: 09/01/2023] [Accepted: 09/05/2023] [Indexed: 10/26/2023] Open
Abstract
The bacterial cell envelope is involved in all stages of infection and the study of its components and structures is important to understand how bacteria interact with the extracellular milieu. Thanks to new techniques that focus on identifying bacterial surface proteins, we now better understand the specific components involved in host-pathogen interactions. In the fight against the deleterious effects of pathogenic bacteria, bacterial surface proteins (at the cell envelope) are important targets as they play crucial roles in the colonization and infection of host tissues. These surface proteins serve functions such as protection, secretion, biofilm formation, nutrient intake, metabolism, and virulence. Bacteria use different mechanisms to associate proteins to the cell surface via posttranslational modification, such as the addition of a lipid moiety to create lipoproteins and attachment to the peptidoglycan layer by sortases. In this review, we focus on these types of proteins (and provide examples of others) that are associated with the bacterial cell envelope by posttranslational modifications and their roles in plant infection.
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Affiliation(s)
- Andrés de Sandozequi
- Departamento de Ingeniería Celular y BiocatálisisInstituto de BiotecnologíaCuernavacaMéxico
| | - Claudia Martínez‐Anaya
- Departamento de Ingeniería Celular y BiocatálisisInstituto de BiotecnologíaCuernavacaMéxico
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Reyes-Umana VM, Coates JD. A description of the genus Denitromonas nom. rev.: Denitromonas iodatirespirans sp. nov., a novel iodate-reducing bacterium, and two novel perchlorate-reducing bacteria, Denitromonas halophila and Denitromonas ohlonensis, isolated from San Francisco Bay intertidal mudflats. Microbiol Spectr 2023; 11:e0091523. [PMID: 37772843 PMCID: PMC10581121 DOI: 10.1128/spectrum.00915-23] [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: 03/03/2023] [Accepted: 08/04/2023] [Indexed: 09/30/2023] Open
Abstract
The genus Denitromonas is currently a non-validated taxon that has been identified in several recent publications as members of microbial communities arising from marine environments. Very little is known about the biology of Denitromonas spp., and no pure cultures are presently found in any culture collections. The current epitaph of Denitromonas was given to the organism under the assumption that all members of this genus are denitrifying bacteria. This study performs phenotypic and genomic analyses on three new Denitromonas spp. isolated from tidal mudflats in the San Francisco Bay. We demonstrate that Denitromonas spp. are indeed all facultative denitrifying bacteria that utilize a variety of carbon sources such as acetate, lactate, and succinate. In addition, individual strains also use the esoteric electron acceptors perchlorate, chlorate, and iodate. Both 16S and Rps/Rpl phylogenetic analyses place Denitromonas spp. as a deep branching clade in the family Zoogloeaceae, separate from either Thauera spp., Azoarcus spp., or Aromatoleum spp. Genome sequencing reveals a G + C content ranging from 63.72% to 66.54%, and genome sizes range between 4.39 and 5.18 Mb. Genes for salt tolerance and denitrification are distinguishing features that separate Denitromonas spp. from the closely related Azoarcus and Aromatoleum genera. IMPORTANCE The genus Denitromonas is currently a non-validated taxon that has been identified in several recent publications as members of microbial communities arising from marine environments. Very little is known about the biology of Denitromonas spp., and no pure cultures are presently found in any culture collections. The current epitaph of Denitromonas was given to the organism under the assumption that all members of this genus are denitrifying bacteria. This study performs phenotypic and genomic analyses on three Denitromonas spp., Denitromonas iodatirespirans sp. nov.-a novel iodate-reducing bacterium-and two novel perchlorate-reducing bacteria, Denitromonas halophila and Denitromonas ohlonensis, isolated from San Francisco Bay intertidal mudflats.
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Affiliation(s)
- Victor M. Reyes-Umana
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - John D. Coates
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
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Obeng EM, Fulcher AJ, Wagstaff KM. Harnessing sortase A transpeptidation for advanced targeted therapeutics and vaccine engineering. Biotechnol Adv 2023; 64:108108. [PMID: 36740026 DOI: 10.1016/j.biotechadv.2023.108108] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 01/29/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
The engineering of potent prophylactic and therapeutic complexes has always required careful protein modification techniques with seamless capabilities. In this light, methods that favor unobstructed multivalent targeting and correct antigen presentations remain essential and very demanding. Sortase A (SrtA) transpeptidation has exhibited these attributes in various settings over the years. However, its applications for engineering avidity-inspired therapeutics and potent vaccines have yet to be significantly noticed, especially in this era where active targeting and multivalent nanomedications are in great demand. This review briefly presents the SrtA enzyme and its associated transpeptidation activity and describes interesting sortase-mediated protein engineering and chemistry approaches for achieving multivalent therapeutic and antigenic responses. The review further highlights advanced applications in targeted delivery systems, multivalent therapeutics, adoptive cellular therapy, and vaccine engineering. These innovations show the potential of sortase-mediated techniques in facilitating the development of simple plug-and-play nanomedicine technologies against recalcitrant diseases and pandemics such as cancer and viral infections.
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Affiliation(s)
- Eugene M Obeng
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
| | - Alex J Fulcher
- Monash Micro Imaging, Monash University, Clayton, VIC 3800, Australia
| | - Kylie M Wagstaff
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
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6
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Malik A, Shoombuatong W, Kim CB, Manavalan B. GPApred: The first computational predictor for identifying proteins with LPXTG-like motif using sequence-based optimal features. Int J Biol Macromol 2023; 229:529-538. [PMID: 36596370 DOI: 10.1016/j.ijbiomac.2022.12.315] [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: 10/19/2022] [Revised: 12/19/2022] [Accepted: 12/28/2022] [Indexed: 01/02/2023]
Abstract
The cell surface proteins of gram-positive bacteria are involved in many important biological functions, including the infection of host cells. Owing to their virulent nature, these proteins are also considered strong candidates for potential drug or vaccine targets. Among the various cell surface proteins of gram-positive bacteria, LPXTG-like proteins form a major class. These proteins have a highly conserved C-terminal cell wall sorting signal, which consists of an LPXTG sequence motif, a hydrophobic domain, and a positively charged tail. These surface proteins are targeted to the cell envelope by a sortase enzyme via transpeptidation. A variety of LPXTG-like proteins have been experimentally characterized; however, their number in public databases has increased owing to extensive bacterial genome sequencing without proper annotation. In the absence of experimental characterization, identifying and annotating these sequences is extremely challenging. Therefore, in this study, we developed the first machine learning-based predictor called GPApred, which can identify LPXTG-like proteins from their primary sequences. Using a newly constructed benchmark dataset, we explored different classifiers and five feature encodings and their hybrids. Optimal features were derived using the recursive feature elimination method, and these features were then trained using a support vector machine algorithm. The performance of different models was evaluated using independent datasets, and a final model (GPApred) was selected based on consistency during cross-validation and independent assessment. GPApred can be an effective tool for predicting LPXTG-like sequences and can be further employed for functional characterization or drug targeting. Availability: https://procarb.org/gpapred/.
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Affiliation(s)
- Adeel Malik
- Institute of Intelligence Informatics Technology, Sangmyung University, Seoul 03016, Republic of Korea
| | - Watshara Shoombuatong
- Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, Bangkok 10700, Thailand
| | - Chang-Bae Kim
- Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea.
| | - Balachandran Manavalan
- Computational Biology and Bioinformatics Laboratory, Department of Integrative Biotechnology, College of Biotechnology and Bioengineering, Sungkyunkwan University, Suwon 16419, Gyeonggi-do, Republic of Korea.
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7
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Malik A, Subramaniyam S, Kim CB, Manavalan B. SortPred: The first machine learning based predictor to identify bacterial sortases and their classes using sequence-derived information. Comput Struct Biotechnol J 2021; 20:165-174. [PMID: 34976319 PMCID: PMC8703055 DOI: 10.1016/j.csbj.2021.12.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/12/2022] Open
Abstract
Sortase enzymes are cysteine transpeptidases that embellish the surface of Gram-positive bacteria with various proteins thereby allowing these microorganisms to interact with their neighboring environment. It is known that several of their substrates can cause pathological implications, so researchers have focused on the development of sortase inhibitors. Currently, six different classes of sortases (A-F) are recognized. However, with the extensive application of bacterial genome sequencing projects, the number of potential sortases in the public databases has exploded, presenting considerable challenges in annotating these sequences. It is very laborious and time-consuming to characterize these sortase classes experimentally. Therefore, this study developed the first machine-learning-based two-layer predictor called SortPred, where the first layer predicts the sortase from the given sequence and the second layer predicts their class from the predicted sortase. To develop SortPred, we constructed an original benchmarking dataset and investigated 31 feature descriptors, primarily on five feature encoding algorithms. Afterward, each of these descriptors were trained using a random forest classifier and their robustness was evaluated with an independent dataset. Finally, we selected the final model independently for both layers depending on the performance consistency between cross-validation and independent evaluation. SortPred is expected to be an effective tool for identifying bacterial sortases, which in turn may aid in designing sortase inhibitors and exploring their functions. The SortPred webserver and a standalone version are freely accessible at: https://procarb.org/sortpred.
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Affiliation(s)
- Adeel Malik
- Institute of Intelligence Informatics Technology, Sangmyung University, Seoul 03016, Republic of Korea
| | | | - Chang-Bae Kim
- Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea
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N Vijayan A, Refaei MA, Silva RN, Tsang P, Zhang P. Detection of Sortase A and Identification of Its Inhibitors by Paramagnetic Nanoparticle-Assisted Nuclear Relaxation. Anal Chem 2021; 93:15430-15437. [PMID: 34757710 DOI: 10.1021/acs.analchem.1c03271] [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
Sortase A is a virulence factor responsible for the attachment of surface proteins to Staphylococcus aureus and other Gram-positive bacteria. Inhibitors of this enzyme are potential anti-infective agents. Herein, a new highly selective magnetic relaxation-based method for screening potential sortase A inhibitors is described. A 13-amino acid-long peptide substrate of sortase A is conjugated to SiO2-EDTA-Gd NPs. In the presence of sortase A, the LPXTG motif on the peptide strand is cleaved resulting in a shortened peptide as well as a reduced water T2 value whose magnitude is dependent on the concentration of sortase A. The detection limit is determined to be 76 pM. In contrast, the presence of sortase A inhibitors causes the T2 to remain at a higher value. The proposed method is used to characterize inhibition of sortase A by curcumin and 4-(hydroxymercuri)benzoic acid with an IC50 value of 12.9 ± 1.6 μM and 130 ± 1.76 μM, respectively. Furthermore, this method was successfully applied to detect sortase A activity in bacterial suspensions. The feasibility to screen different inhibitors in Escherichia coli and S. aureus suspensions was demonstrated. This method is fast and potentially useful to rapidly screen possible inhibitors of sortase A in bacterial suspensions, thereby aiding in the development of antibacterial agents targeting Gram-positive bacteria.
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Affiliation(s)
- Anjaly N Vijayan
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, United States
| | - Mary Anne Refaei
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, United States
| | - Rebecca N Silva
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, United States
| | - Pearl Tsang
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, United States
| | - Peng Zhang
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, United States
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9
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Sapra R, Rajora AK, Kumar P, Maurya GP, Pant N, Haridas V. Chemical Biology of Sortase A Inhibition: A Gateway to Anti-infective Therapeutic Agents. J Med Chem 2021; 64:13097-13130. [PMID: 34516107 DOI: 10.1021/acs.jmedchem.1c00386] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Staphylococcus aureus is the leading cause of hospital-acquired infections. The enzyme sortase A, present on the cell surface of S. aureus, plays a key role in bacterial virulence without affecting the bacterial viability. Inhibition of sortase A activity offers a powerful but clinically less explored therapeutic strategy, as it offers the possibility of not inducing any selective pressure on the bacteria to evolve drug-resistant strains. In this Perspective, we offer a chemical space narrative for the design of sortase A inhibitors, as delineated into three broad domains: peptidomimetics, natural products, and synthetic small molecules. This provides immense opportunities for medicinal chemists to alleviate the ever-growing crisis of antibiotic resistance.
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Affiliation(s)
- Rachit Sapra
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Amit K Rajora
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Pushpendra Kumar
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Govind P Maurya
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Nalin Pant
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - V Haridas
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-110016, India
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Yang H, Qu J, Zou W, Shen W, Chen X. An overview and future prospects of recombinant protein production in Bacillus subtilis. Appl Microbiol Biotechnol 2021; 105:6607-6626. [PMID: 34468804 DOI: 10.1007/s00253-021-11533-2] [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] [Received: 04/07/2021] [Revised: 08/12/2021] [Accepted: 08/15/2021] [Indexed: 12/27/2022]
Abstract
Bacillus subtilis is a well-characterized Gram-positive bacterium and a valuable host for recombinant protein production because of its efficient secretion ability, high yield, and non-toxicity. Here, we comprehensively review the recent studies on recombinant protein production in B. subtilis to update and supplement other previous reviews. We have focused on several aspects, including optimization of B. subtilis strains, enhancement and regulation of expression, improvement of secretion level, surface display of proteins, and fermentation optimization. Among them, optimization of B. subtilis strains mainly involves undirected chemical/physical mutagenesis and selection and genetic manipulation; enhancement and regulation of expression comprises autonomous plasmid and integrated expression, promoter regulation and engineering, and fine-tuning gene expression based on proteases and molecular chaperones; improvement of secretion level predominantly involves secretion pathway and signal peptide screening and optimization; surface display of proteins includes surface display of proteins on spores or vegetative cells; and fermentation optimization incorporates medium optimization, process condition optimization, and feeding strategy optimization. Furthermore, we propose some novel methods and future challenges for recombinant protein production in B. subtilis.Key points• A comprehensive review on recombinant protein production in Bacillus subtilis.• Novel techniques facilitate recombinant protein expression and secretion.• Surface display of proteins has significant potential for different applications.
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Affiliation(s)
- Haiquan Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
| | - Jinfeng Qu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Wei Zou
- College of Bioengineering, Sichuan University of Science & Engineering, Yibin, 644000, Sichuan, China
| | - Wei Shen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Xianzhong Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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Susmitha A, Bajaj H, Madhavan Nampoothiri K. The divergent roles of sortase in the biology of Gram-positive bacteria. ACTA ACUST UNITED AC 2021; 7:100055. [PMID: 34195501 PMCID: PMC8225981 DOI: 10.1016/j.tcsw.2021.100055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/16/2022]
Abstract
The bacterial cell wall contains numerous surface-exposed proteins, which are covalently anchored and assembled by a sortase family of transpeptidase enzymes. The sortase are cysteine transpeptidases that catalyzes the covalent attachment of surface protein to the cell wall peptidoglycan. Among the reported six classes of sortases, each distinct class of sortase plays a unique biological role in anchoring a variety of surface proteins to the peptidoglycan of both pathogenic and non-pathogenic Gram-positive bacteria. Sortases not only exhibit virulence and pathogenesis properties to host cells, but also possess a significant role in gut retention and immunomodulation in probiotic microbes. The two main distinct functions are to attach proteins directly to the cell wall or assemble pili on the microbial surface. This review provides a compendium of the distribution of different classes of sortases present in both pathogenic and non-pathogenic Gram-positive bacteria and also the noteworthy role played by them in bacterial cell wall assembly which enables each microbe to effectively interact with its environment.
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Affiliation(s)
- Aliyath Susmitha
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Harsha Bajaj
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India
| | - Kesavan Madhavan Nampoothiri
- Microbial Processes and Technology Division, CSIR - National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695019, Kerala, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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12
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Alharthi S, Alavi SE, Moyle PM, Ziora ZM. Sortase A (SrtA) inhibitors as an alternative treatment for superbug infections. Drug Discov Today 2021; 26:2164-2172. [PMID: 33781954 DOI: 10.1016/j.drudis.2021.03.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/01/2021] [Accepted: 03/19/2021] [Indexed: 12/28/2022]
Abstract
Virulence factor, sortase A (SrtA), has crucial roles in the pathogenesis of Gram-positive superbugs. SrtA is a bacterial cell membrane enzyme that anchors crucial virulence factors to the cell wall surface of Gram-positive bacteria. SrtA is not necessary for bacterial growth and viability and is conveniently accessible in the cell membrane; therefore, it is an ideal target for antivirulence drug development. In this review, we focus on antimicrobial resistance (AMR)-expressing bacteria and SrtA as a potential target for overcoming AMR. The mechanism of action of SrtA and its inhibition by various types of inhibitors, such as synthetic small molecules, peptides, and natural products, are provided. Future SrtA research perspectives for alternative drug development to antibiotics are also proposed.
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Affiliation(s)
- Sitah Alharthi
- School of Pharmacy, The University of Queensland, Woolloongabba, Qld 4102, Australia; Department of Pharmaceutical Science, School of Pharmacy, Shaqra University, Riyadh, Saudi Arabia
| | - Seyed Ebrahim Alavi
- School of Pharmacy, The University of Queensland, Woolloongabba, Qld 4102, Australia
| | - Peter Michael Moyle
- School of Pharmacy, The University of Queensland, Woolloongabba, Qld 4102, Australia.
| | - Zyta Maria Ziora
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Qld 4067, Australia.
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13
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Anchoring surface proteins to the bacterial cell wall by sortase enzymes: how it started and what we know now. Curr Opin Microbiol 2021; 60:73-79. [PMID: 33611145 DOI: 10.1016/j.mib.2021.01.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/14/2021] [Accepted: 01/27/2021] [Indexed: 11/20/2022]
Abstract
In Gram-positive bacteria, the peptidoglycan serves as a placeholder for surface display of a unique class of monomeric and polymeric proteins, or pili - the precursors of which harbor a cell wall sorting signal with LPXTG motif that is recognized by a conserved transpeptidase enzyme called sortase. Since this original discovery over two decades ago, extensive genetic, biochemical and structural studies have illuminated the basic mechanisms of sortase-mediated cell wall anchoring of surface proteins and pili. We now know how LPXTG-containing surface proteins are folded post-translocationally, how sortase enzymes recognize substrates, and how a remnant of the cell wall sorting signal modulates intramembrane signaling. In this review, we will highlight new findings from a few model experimental paradigms and present future prospects for the field.
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14
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Immunoinformatic approach for the evaluation of sortase C and E proteins as vaccine targets against caseous lymphadenitis. INFORMATICS IN MEDICINE UNLOCKED 2021. [DOI: 10.1016/j.imu.2021.100718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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15
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Insights into the biochemical and functional characterization of sortase E transpeptidase of Corynebacterium glutamicum. Biochem J 2020; 476:3835-3847. [PMID: 31815278 DOI: 10.1042/bcj20190812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 12/30/2022]
Abstract
Most Gram-positive bacteria contain a membrane-bound transpeptidase known as sortase which covalently incorporates the surface proteins on to the cell wall. The sortase-displayed protein structures are involved in cell attachment, nutrient uptake and aerial hyphae formation. Among the six classes of sortase (A-F), sortase A of S. aureus is the well-characterized housekeeping enzyme considered as an ideal drug target and a valuable biochemical reagent for protein engineering. Similar to SrtA, class E sortase in GC rich bacteria plays a housekeeping role which is not studied extensively. However, C. glutamicum ATCC 13032, an industrially important organism known for amino acid production, carries a single putative sortase (NCgl2838) gene but neither in vitro peptide cleavage activity nor biochemical characterizations have been investigated. Here, we identified that the gene is having a sortase activity and analyzed its structural similarity with Cd-SrtF. The purified enzyme showed a greater affinity toward LAXTG substrate with a calculated KM of 12 ± 1 µM, one of the highest affinities reported for this class of enzyme. Moreover, site-directed mutation studies were carried to ascertain the structure functional relationship of Cg-SrtE and all these are new findings which will enable us to perceive exciting protein engineering applications with this class of enzyme from a non-pathogenic microbe.
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16
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Sue CK, McConnell SA, Ellis-Guardiola K, Muroski J, McAllister RA, Yu J, Alvarez AI, Chang C, Ogorzalek Loo RR, Loo JA, Ton-That H, Clubb RT. Kinetics and Optimization of the Lysine-Isopeptide Bond Forming Sortase Enzyme from Corynebacterium diphtheriae. Bioconjug Chem 2020; 31:1624-1634. [PMID: 32396336 PMCID: PMC8153732 DOI: 10.1021/acs.bioconjchem.0c00163] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Site-specifically modified protein bioconjugates have important applications in biology, chemistry, and medicine. Functionalizing specific protein side chains with enzymes using mild reaction conditions is of significant interest, but remains challenging. Recently, the lysine-isopeptide bond forming activity of the sortase enzyme that builds surface pili in Corynebacterium diphtheriae (CdSrtA) has been reconstituted in vitro. A mutationally activated form of CdSrtA was shown to be a promising bioconjugating enzyme that can attach Leu-Pro-Leu-Thr-Gly peptide fluorophores to a specific lysine residue within the N-terminal domain of the SpaA protein (NSpaA), enabling the labeling of target proteins that are fused to NSpaA. Here we present a detailed analysis of the CdSrtA catalyzed protein labeling reaction. We show that the first step in catalysis is rate limiting, which is the formation of the CdSrtA-peptide thioacyl intermediate that subsequently reacts with a lysine ε-amine in NSpaA. This intermediate is surprisingly stable, limiting spurious proteolysis of the peptide substrate. We report the discovery of a new enzyme variant (CdSrtAΔ) that has significantly improved transpeptidation activity, because it completely lacks an inhibitory polypeptide appendage ("lid") that normally masks the active site. We show that the presence of the lid primarily impairs formation of the thioacyl intermediate and not the recognition of the NSpaA substrate. Quantitative measurements reveal that CdSrtAΔ generates its cross-linked product with a catalytic turnover number of 1.4 ± 0.004 h-1 and that it has apparent KM values of 0.16 ± 0.04 and 1.6 ± 0.3 mM for its NSpaA and peptide substrates, respectively. CdSrtAΔ is 7-fold more active than previously studied variants, labeling >90% of NSpaA with peptide within 6 h. The results of this study further improve the utility of CdSrtA as a protein labeling tool and provide insight into the enzyme catalyzed reaction that underpins protein labeling and pilus biogenesis.
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Affiliation(s)
- Christopher K. Sue
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Scott A. McConnell
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Ken Ellis-Guardiola
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - John Muroski
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Rachel A. McAllister
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Justin Yu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Ana I. Alvarez
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Chungyu Chang
- Molecular Biology Institute and the University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Rachel R. Ogorzalek Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Joseph A. Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- Molecular Biology Institute and the University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Hung Ton-That
- Molecular Biology Institute and the University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
| | - Robert T. Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
- Molecular Biology Institute and the University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095
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17
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Revitt-Mills SA, Watts TD, Lyras D, Adams V, Rood JI. The ever-expanding tcp conjugation locus of pCW3 from Clostridium perfringens. Plasmid 2020; 113:102516. [PMID: 32526229 DOI: 10.1016/j.plasmid.2020.102516] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/20/2020] [Accepted: 04/26/2020] [Indexed: 12/13/2022]
Abstract
The spore-forming, anaerobic Gram positive pathogen Clostridium perfringens encodes many of its disease-causing toxins on closely related conjugative plasmids. Studies of the tetracycline resistance plasmid pCW3 have identified many of the genes involved in conjugative transfer, which are located in the tcp conjugation locus. Upstream of this locus is an uncharacterised region (the cnaC region) that is highly conserved. This study examined the importance in pCW3 conjugation of several highly conserved proteins encoded in the cnaC region. Conjugative mating studies suggested that the SrtD, TcpN and Dam proteins were required for efficient pCW3 transfer between C. perfringens cells from the same strain background. The requirement of these proteins for conjugation was amplified in matings between C. perfringens cells of different strain backgrounds. Additionally, the putative collagen adhesin protein, CnaC, was only required for the optimal transfer of pCW3 between cells of different strain backgrounds. Based on these studies we postulate that CnaC, SrtD, TcpN and Dam are involved in enhancing the transfer frequency of pCW3. These studies have led to a significant expansion of the tcp conjugation locus, which now encompasses a 19 kb region.
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Affiliation(s)
- Sarah A Revitt-Mills
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Victoria 3800, Australia.
| | - Thomas D Watts
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Dena Lyras
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Vicki Adams
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Victoria 3800, Australia
| | - Julian I Rood
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Victoria 3800, Australia
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18
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Ramirez NA, Das A, Ton-That H. New Paradigms of Pilus Assembly Mechanisms in Gram-Positive Actinobacteria. Trends Microbiol 2020; 28:999-1009. [PMID: 32499101 DOI: 10.1016/j.tim.2020.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/08/2020] [Accepted: 05/14/2020] [Indexed: 02/06/2023]
Abstract
Adhesive pili in Gram-positive bacteria represent a variety of extracellular multiprotein polymers that mediate bacterial colonization of specific host tissues and associated pathogenesis. Pili are assembled in two distinct but coupled steps, an orderly crosslinking of pilin monomers and subsequent anchoring of the polymer to peptidoglycan, catalyzed by two transpeptidase enzymes - the pilus-specific sortase and the housekeeping sortase. Here, we review this biphasic assembly mechanism based on studies of two prototypical models, the heterotrimeric pili in Corynebacterium diphtheriae and the heterodimeric pili in Actinomyces oris, highlighting some newly emerged basic paradigms. The disparate mechanisms of protein ligation mediated by the pilus-specific sortase and the spatial positioning of adhesive pili on the cell surface modulated by the housekeeping sortase are among the notable highlights.
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Affiliation(s)
- Nicholas A Ramirez
- Molecular Biology Institute, University of California, Los Angeles, CA, USA
| | - Asis Das
- Department of Medicine, Neag Comprehensive Cancer Center, University of Connecticut Health Center, Farmington, CT, USA
| | - Hung Ton-That
- Molecular Biology Institute, University of California, Los Angeles, CA, USA; Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, CA, USA.
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19
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Gosschalk JE, Chang C, Sue CK, Siegel SD, Wu C, Kattke MD, Yi SW, Damoiseaux R, Jung ME, Ton-That H, Clubb RT. A Cell-based Screen in Actinomyces oris to Identify Sortase Inhibitors. Sci Rep 2020; 10:8520. [PMID: 32444661 PMCID: PMC7244523 DOI: 10.1038/s41598-020-65256-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 04/20/2020] [Indexed: 12/12/2022] Open
Abstract
Sortase enzymes are attractive antivirulence drug targets that attach virulence factors to the surface of Staphylococcus aureus and other medically significant bacterial pathogens. Prior efforts to discover a useful sortase inhibitor have relied upon an in vitro activity assay in which the enzyme is removed from its native site on the bacterial surface and truncated to improve solubility. To discover inhibitors that are effective in inactivating sortases in vivo, we developed and implemented a novel cell-based screen using Actinomyces oris, a key colonizer in the development of oral biofilms. A. oris is unique because it exhibits sortase-dependent growth in cell culture, providing a robust phenotype for high throughput screening (HTS). Three molecules representing two unique scaffolds were discovered by HTS and disrupt surface protein display in intact cells and inhibit enzyme activity in vitro. This represents the first HTS for sortase inhibitors that relies on the simple metric of cellular growth and suggests that A. oris may be a useful platform for discovery efforts targeting sortase.
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Affiliation(s)
- Jason E Gosschalk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA.,UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, USA
| | - Chungyu Chang
- Division of Oral Biology and Medicine, University of California, Los Angeles, USA
| | - Christopher K Sue
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA.,UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, USA
| | - Sara D Siegel
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
| | - Chenggang Wu
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
| | - Michele D Kattke
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA.,UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, USA
| | - Sung Wook Yi
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA
| | - Robert Damoiseaux
- Department of Molecular and Medicinal Pharmacology, University of California, Los Angeles, USA.,California NanoSystems Institute, University of California, Los Angeles, USA
| | - Michael E Jung
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA.,Molecular Biology Institute, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA, 90095, USA
| | - Hung Ton-That
- Division of Oral Biology and Medicine, University of California, Los Angeles, USA. .,Department of Molecular and Medicinal Pharmacology, University of California, Los Angeles, USA.
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, USA. .,UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, USA. .,Molecular Biology Institute, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA, 90095, USA.
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20
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Kang CY, Huang IH, Chou CC, Wu TY, Chang JC, Hsiao YY, Cheng CH, Tsai WJ, Hsu KC, Wang S. Functional analysis of Clostridium difficile sortase B reveals key residues for catalytic activity and substrate specificity. J Biol Chem 2020; 295:3734-3745. [PMID: 32005667 PMCID: PMC7076211 DOI: 10.1074/jbc.ra119.011322] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 01/31/2020] [Indexed: 01/07/2023] Open
Abstract
Most of Gram-positive bacteria anchor surface proteins to the peptidoglycan cell wall by sortase, a cysteine transpeptidase that targets proteins displaying a cell wall sorting signal. Unlike other bacteria, Clostridium difficile, the major human pathogen responsible for antibiotic-associated diarrhea, has only a single functional sortase (SrtB). Sortase's vital importance in bacterial virulence has been long recognized, and C. difficile sortase B (Cd-SrtB) has become an attractive therapeutic target for managing C. difficile infection. A better understanding of the molecular activity of Cd-SrtB may help spur the development of effective agents against C. difficile infection. In this study, using site-directed mutagenesis, biochemical and biophysical tools, LC-MS/MS, and crystallographic analyses, we identified key residues essential for Cd-SrtB catalysis and substrate recognition. To the best of our knowledge, we report the first evidence that a conserved serine residue near the active site participates in the catalytic activity of Cd-SrtB and also SrtB from Staphylococcus aureus The serine residue indispensable for SrtB activity may be involved in stabilizing a thioacyl-enzyme intermediate because it is neither a nucleophilic residue nor a substrate-interacting residue, based on the LC-MS/MS data and available structural models of SrtB-substrate complexes. Furthermore, we also demonstrated that residues 163-168 located on the β6/β7 loop of Cd-SrtB dominate specific recognition of the peptide substrate PPKTG. The results of this work reveal key residues with roles in catalysis and substrate specificity of Cd-SrtB.
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Affiliation(s)
- Chia-Yu Kang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan
| | - I-Hsiu Huang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan
| | - Chi-Chi Chou
- Institute of Biological Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan
| | - Tsai-Yu Wu
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan
| | - Jyun-Cyuan Chang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan
| | - Yu-Yuan Hsiao
- Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu 300, Taiwan,Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan,Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Cheng-Hsuan Cheng
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan,Institute of Basic Medical Science, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Wei-Jiun Tsai
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan,Institute of Basic Medical Science, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Kai-Cheng Hsu
- Graduate Institute of Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan
| | - Shuying Wang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan 701, Taiwan,Institute of Basic Medical Science, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan, To whom correspondence should be addressed:
Dept. of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan. Tel.:
886-6-2353535, Ext. 5634; Fax:
886-6-2082705; E-mail:
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21
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Malik A, Kim YR, Jang IH, Hwang S, Oh DC, Kim SB. Genome-based analysis for the bioactive potential of Streptomyces yeochonensis CN732, an acidophilic filamentous soil actinobacterium. BMC Genomics 2020; 21:118. [PMID: 32013859 PMCID: PMC6998099 DOI: 10.1186/s12864-020-6468-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/08/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Acidophilic members of the genus Streptomyces can be a good source for novel secondary metabolites and degradative enzymes of biopolymers. In this study, a genome-based approach on Streptomyces yeochonensis CN732, a representative neutrotolerant acidophilic streptomycete, was employed to examine the biosynthetic as well as enzymatic potential, and also presence of any genetic tools for adaptation in acidic environment. RESULTS A high quality draft genome (7.8 Mb) of S. yeochonensis CN732 was obtained with a G + C content of 73.53% and 6549 protein coding genes. The in silico analysis predicted presence of multiple biosynthetic gene clusters (BGCs), which showed similarity with those for antimicrobial, anticancer or antiparasitic compounds. However, the low levels of similarity with known BGCs for most cases suggested novelty of the metabolites from those predicted gene clusters. The production of various novel metabolites was also confirmed from the combined high performance liquid chromatography-mass spectrometry analysis. Through comparative genome analysis with related Streptomyces species, genes specific to strain CN732 and also those specific to neutrotolerant acidophilic species could be identified, which showed that genes for metabolism in diverse environment were enriched among acidophilic species. In addition, the presence of strain specific genes for carbohydrate active enzymes (CAZyme) along with many other singletons indicated uniqueness of the genetic makeup of strain CN732. The presence of cysteine transpeptidases (sortases) among the BGCs was also observed from this study, which implies their putative roles in the biosynthesis of secondary metabolites. CONCLUSIONS This study highlights the bioactive potential of strain CN732, an acidophilic streptomycete with regard to secondary metabolite production and biodegradation potential using genomics based approach. The comparative genome analysis revealed genes specific to CN732 and also those among acidophilic species, which could give some insights into the adaptation of microbial life in acidic environment.
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Affiliation(s)
- Adeel Malik
- Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Yu Ri Kim
- Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - In Hee Jang
- Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Sunghoon Hwang
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dong-Chan Oh
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seung Bum Kim
- Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon, 34134, Republic of Korea.
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22
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Structural studies of Staphylococcus aureus Sortase inhibiton via Conus venom peptides. Arch Biochem Biophys 2019; 671:87-102. [DOI: 10.1016/j.abb.2019.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/09/2019] [Accepted: 06/11/2019] [Indexed: 12/13/2022]
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23
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Gomand F, Borges F, Guerin J, El-Kirat-Chatel S, Francius G, Dumas D, Burgain J, Gaiani C. Adhesive Interactions Between Lactic Acid Bacteria and β-Lactoglobulin: Specificity and Impact on Bacterial Location in Whey Protein Isolate. Front Microbiol 2019; 10:1512. [PMID: 31333617 PMCID: PMC6617547 DOI: 10.3389/fmicb.2019.01512] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 06/17/2019] [Indexed: 12/11/2022] Open
Abstract
In the last decade, there has been an increasing interest in the potential health effects associated with the consumption of lactic acid bacteria (LAB) in foods. Some of these bacteria such as Lactobacillus rhamnosus GG (LGG) are known to adhere to milk components, which may impact their distribution and protection within dairy matrices and therefore is likely to modulate the efficiency of their delivery. However, the adhesive behavior of most LAB, as well as its effect on food structuration and on the final bacterial distribution within the food matrix remain very poorly studied. Using a recently developed high-throughput approach, we have screened a collection of 73 LAB strains for their adhesive behavior toward the major whey protein β-lactoglobulin. Adhesion was then studied by genomics in relation to common bacterial surface characteristics such as pili and adhesion-related domain containing proteins. Representative adhesive and non-adhesive strains have been studied in further depth through biophysical measurement using atomic force microscopy (AFM) and a relation with bacterial distribution in whey protein isolate (WPI) solution has been established. AFM measurements have revealed that bacterial adhesion to β-lactoglobulin is highly specific and cannot be predicted accurately using only genomic information. Non-adhesive strains were found to remain homogeneously distributed in solution whereas adhesive strains gathered in flocs. These findings show that several LAB strains are able to adhere to β-lactoglobulin, whereas this had only been previously observed on LGG. We also show that these adhesive interactions present similar characteristics and are likely to impact bacterial location and distribution in dairy matrices containing β-lactoglobulin. This may help with designing more efficient dairy food matrices for optimized LAB delivery.
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Affiliation(s)
- Faustine Gomand
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Frédéric Borges
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Justine Guerin
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Sofiane El-Kirat-Chatel
- CNRS, Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, Université de Lorraine, Villers-lès-Nancy, France
| | - Gregory Francius
- CNRS, Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, Université de Lorraine, Villers-lès-Nancy, France
| | - Dominique Dumas
- Plateforme d'Imagerie et de Biophysique Cellulaire de Nancy (PTIBC IBISA-NANCY), UMS 2008, IMOPA UMR 7365 - Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Jennifer Burgain
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Claire Gaiani
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, Vandœuvre-lès-Nancy, France
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24
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Anderl A, Ferlemann C, Muth M, Henkel-Gupalo A, Ebenig A, Brenner-Weiß G, Kolmar H, Fuchsbauer HL. Biochemical study of sortase E2 from Streptomyces mobaraensis and determination of transglutaminase cross-linking sites. FEBS Lett 2019; 593:1944-1956. [PMID: 31155711 DOI: 10.1002/1873-3468.13466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/27/2019] [Accepted: 05/29/2019] [Indexed: 12/15/2022]
Abstract
Distinct streptomycetes such as Streptomyces mobaraensis produce the protein cross-linking enzyme transglutaminase. Bioinformatic analysis predicted the occurrence of seven sortases exerting transpeptidation reactions similarly to transglutaminase. Here, we report the production and characterization of sortase E2 (Sm-SrtE2) solubilized by removal of its membrane anchor domain. Sm-SrtE2 activity was measured using pentapeptides predicted to be cell wall sorting signals of putative sortase substrate proteins. Preferred linkage to Gly3 by Sm-SrtE2 was in the order LAETG>>LAHTG>>LAQTG~LANTG>LARTG. Chaplin 1 from S. mobaraensis was further demonstrated to be an excellent substrate of both the intrinsic Sm-SrtE2 and transglutaminase. The unexpected discovery showing Gln-62 and Gln-65 of Δ1-50 -Sm-SrtE2 as transglutaminase cross-linking sites suggests that low enzyme stability might be due to anchor domain truncation and a disordered N terminus.
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Affiliation(s)
- Anita Anderl
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences of Darmstadt, Germany.,Department of Chemistry, Technische Universität Darmstadt, Germany
| | - Cathrin Ferlemann
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences of Darmstadt, Germany
| | - Marius Muth
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences of Darmstadt, Germany.,Bioengineering and Biosystems, Institute of Functional Interfaces, Karlsruhe Institute of Technology, Germany
| | - Antonina Henkel-Gupalo
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences of Darmstadt, Germany
| | - Aileen Ebenig
- Department of Chemistry, Technische Universität Darmstadt, Germany
| | - Gerald Brenner-Weiß
- Bioengineering and Biosystems, Institute of Functional Interfaces, Karlsruhe Institute of Technology, Germany
| | - Harald Kolmar
- Department of Chemistry, Technische Universität Darmstadt, Germany
| | - Hans-Lothar Fuchsbauer
- Department of Chemical Engineering and Biotechnology, University of Applied Sciences of Darmstadt, Germany
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25
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A comprehensive in silico analysis of sortase superfamily. J Microbiol 2019; 57:431-443. [DOI: 10.1007/s12275-019-8545-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 01/02/2019] [Accepted: 01/10/2019] [Indexed: 12/22/2022]
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26
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Abstract
To interact with the external environments, bacteria often display long proteinaceous appendages on their cell surface, called pili or fimbriae. These non-flagellar thread-like structures are polymers composed of covalently or non-covalently interacting repeated pilin subunits. Distinct pilus classes can be identified on basis of their assembly pathways, including chaperone-usher pili, type V pili, type IV pili, curli and fap fibers, conjugative and type IV secretion pili, as well as sortase-mediated pili. Pili play versatile roles in bacterial physiology, and can be involved in adhesion and host cell invasion, DNA and protein secretion and uptake, biofilm formation, cell motility and more. Recent advances in structure determination of components involved in the various pilus systems has enabled a better molecular understanding of their mechanisms of assembly and function. In this chapter we describe the diversity in structure, biogenesis and function of the different pilus systems found in Gram-positive and Gram-negative bacteria, and review their potential as anti-microbial targets.
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Affiliation(s)
- Magdalena Lukaszczyk
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
- Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050, Brussels, Belgium
| | - Brajabandhu Pradhan
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
- Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050, Brussels, Belgium
| | - Han Remaut
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium.
- Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050, Brussels, Belgium.
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27
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Stanborough T, Suryadinata R, Fegan N, Powell SM, Tamplin M, Nuttall SD, Chandry PS. Characterisation of the Brochothrix thermosphacta sortase A enzyme. FEMS Microbiol Lett 2018; 365:5056718. [PMID: 30052925 DOI: 10.1093/femsle/fny184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 07/18/2018] [Indexed: 12/11/2022] Open
Abstract
Gram-positive bacteria utilise class A sortases to coat the surface of their cells with a diversity of proteins that facilitate interactions with their environment and play fundamental roles in cell physiology and virulence. A putative sortase A gene was identified in the genome of the poorly studied meat spoilage bacterium Brochothrix thermosphacta. To understand how this bacterium mediates interactions with its environment, an N-terminal truncated, His-tagged variant of this protein (His6-BtSrtA) was expressed and purified. Catalytic activity of recombinant His6-BtSrtA was investigated, including sorting motif recognition of target proteins and bioconjugation activity. Further, the B. thermosphacta genome was examined for the presence of sortase A (SrtA) protein substrates. His6-BtSrtA readily formed intermediate complexes with LPXTG-tagged proteins. Although the reaction was inefficient, nucleophilic attack of the resultant thioacyl intermediates by tri-glycine was observed. Genome examination identified 11 potential SrtA substrates, two of which contained protein domains associated with adherence of pathogens to host extracellular matrix proteins and cells, suggesting the B. thermosphacta SrtA may be indirectly involved in its attachment to meat surfaces. Thus, further work in this area could provide crucial insight into molecular mechanisms involved in the colonisation of meat by B. thermosphacta.
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Affiliation(s)
- Tamsyn Stanborough
- CSIRO Agriculture and Food, Werribee, VIC 3030, Australia.,CSIRO Manufacturing, Parkville, VIC 3030, Australia
| | | | - Narelle Fegan
- CSIRO Agriculture and Food, Werribee, VIC 3030, Australia
| | - Shane M Powell
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Mark Tamplin
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
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28
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Tamanai-Shacoori Z, Smida I, Bousarghin L, Loreal O, Meuric V, Fong SB, Bonnaure-Mallet M, Jolivet-Gougeon A. Roseburia spp.: a marker of health? Future Microbiol 2017; 12:157-170. [PMID: 28139139 DOI: 10.2217/fmb-2016-0130] [Citation(s) in RCA: 410] [Impact Index Per Article: 58.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The genus Roseburia consists of obligate Gram-positive anaerobic bacteria that are slightly curved, rod-shaped and motile by means of multiple subterminal flagella. It includes five species: Roseburia intestinalis, R. hominis, R. inulinivorans, R. faecis and R. cecicola. Gut Roseburia spp. metabolize dietary components that stimulate their proliferation and metabolic activities. They are part of commensal bacteria producing short-chain fatty acids, especially butyrate, affecting colonic motility, immunity maintenance and anti-inflammatory properties. Modification in Roseburia spp. representation may affect various metabolic pathways and is associated with several diseases (including irritable bowel syndrome, obesity, Type 2 diabetes, nervous system conditions and allergies). Roseburia spp. could also serve as biomarkers for symptomatic pathologies (e.g., gallstone formation) or as probiotics for restoration of beneficial flora.
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Affiliation(s)
- Zohreh Tamanai-Shacoori
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France
| | - Imen Smida
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France
| | - Latifa Bousarghin
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France
| | - Olivier Loreal
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France
| | - Vincent Meuric
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France.,CHU Rennes, 2 rue Henri Le Guilloux, 35000 Rennes, France.,Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes, France
| | - Shao Bing Fong
- Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes, France
| | - Martine Bonnaure-Mallet
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France.,CHU Rennes, 2 rue Henri Le Guilloux, 35000 Rennes, France.,Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes, France
| | - Anne Jolivet-Gougeon
- INSERM 1241/NUtrition MEtabolism CANcer/CIMIAD, 2 avenue du Professeur Léon Bernard, Rennes, France.,CHU Rennes, 2 rue Henri Le Guilloux, 35000 Rennes, France.,Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes, France
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29
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Anchoring of LPXTG-Like Proteins to the Gram-Positive Cell Wall Envelope. Curr Top Microbiol Immunol 2017; 404:159-175. [PMID: 27097813 DOI: 10.1007/82_2016_8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In Gram-positive bacteria, protein precursors with a signal peptide and a cell wall sorting signal (CWSS)-which begins with an LPXTG motif, followed by a hydrophobic domain and a tail of positively charged residues-are targeted to the cell envelope by a transpeptidase enzyme call sortase. Evolution and selective pressure gave rise to six classes of sortase, i.e., SrtA-F. Only class C sortases are capable of polymerizing substrates harboring the pilin motif and CWSS into protein polymers known as pili or fimbriae, whereas the others perform cell wall anchoring functions. Regardless of the products generated from these sortases, the basic principle of sortase-catalyzed transpeptidation is the same. It begins with the cleavage of the LPXTG motif, followed by the cross-linking of this cleaved product at the threonine residue to a nucleophile, i.e., an active amino group of the peptidoglycan stem peptide or the lysine residue of the pilin motif. This chapter will summarize the efforts to identify and characterize sortases and their associated pathways with emphasis on the cell wall anchoring function.
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30
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Jacobitz AW, Kattke MD, Wereszczynski J, Clubb RT. Sortase Transpeptidases: Structural Biology and Catalytic Mechanism. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 109:223-264. [PMID: 28683919 DOI: 10.1016/bs.apcsb.2017.04.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Gram-positive bacteria use sortase cysteine transpeptidase enzymes to covalently attach proteins to their cell wall and to assemble pili. In pathogenic bacteria sortases are potential drug targets, as many of the proteins that they display on the microbial surface play key roles in the infection process. Moreover, the Staphylococcus aureus Sortase A (SaSrtA) enzyme has been developed into a valuable biochemical reagent because of its ability to ligate biomolecules together in vitro via a covalent peptide bond. Here we review what is known about the structures and catalytic mechanism of sortase enzymes. Based on their primary sequences, most sortase homologs can be classified into six distinct subfamilies, called class A-F enzymes. Atomic structures reveal unique, class-specific variations that support alternate substrate specificities, while structures of sortase enzymes bound to sorting signal mimics shed light onto the molecular basis of substrate recognition. The results of computational studies are reviewed that provide insight into how key reaction intermediates are stabilized during catalysis, as well as the mechanism and dynamics of substrate recognition. Lastly, the reported in vitro activities of sortases are compared, revealing that the transpeptidation activity of SaSrtA is at least 20-fold faster than other sortases that have thus far been characterized. Together, the results of the structural, computational, and biochemical studies discussed in this review begin to reveal how sortases decorate the microbial surface with proteins and pili, and may facilitate ongoing efforts to discover therapeutically useful small molecule inhibitors.
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Affiliation(s)
- Alex W Jacobitz
- The Molecular Biology Institute and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, CA, United States
| | - Michele D Kattke
- The Molecular Biology Institute and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, CA, United States
| | - Jeff Wereszczynski
- Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, United States
| | - Robert T Clubb
- The Molecular Biology Institute and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, CA, United States.
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Puorger C, Di Girolamo S, Lipps G. Elucidation of the Recognition Sequence of Sortase B from Bacillus anthracis by Using a Newly Developed Liquid Chromatography–Mass Spectrometry-Based Method. Biochemistry 2017; 56:2641-2650. [DOI: 10.1021/acs.biochem.7b00108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chasper Puorger
- Institute for Chemistry and
Bioanalytics, University of Applied Sciences and Arts, Gründenstrasse
40, 4132 Muttenz, Switzerland
| | - Salvatore Di Girolamo
- Institute for Chemistry and
Bioanalytics, University of Applied Sciences and Arts, Gründenstrasse
40, 4132 Muttenz, Switzerland
| | - Georg Lipps
- Institute for Chemistry and
Bioanalytics, University of Applied Sciences and Arts, Gründenstrasse
40, 4132 Muttenz, Switzerland
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32
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Khare B, V L Narayana S. Pilus biogenesis of Gram-positive bacteria: Roles of sortases and implications for assembly. Protein Sci 2017; 26:1458-1473. [PMID: 28493331 DOI: 10.1002/pro.3191] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/28/2017] [Accepted: 05/03/2017] [Indexed: 12/26/2022]
Abstract
Successful adherence, colonization, and survival of Gram-positive bacteria require surface proteins, and multiprotein assemblies called pili. These surface appendages are attractive pharmacotherapeutic targets and understanding their assembly mechanisms is essential for identifying a new class of 'anti-infectives' that do not elicit microbial resistance. Molecular details of the Gram-negative pilus assembly are available indepth, but the Gram-positive pilus biogenesis is still an emerging field and investigations continue to reveal novel insights into this process. Pilus biogenesis in Gram-positive bacteria is a biphasic process that requires enzymes called pilus-sortases for assembly and a housekeeping sortase for covalent attachment of the assembled pilus to the peptidoglycan cell wall. Emerging structural and functional data indicate that there are at least two groups of Gram-positive pili, which require either the Class C sortase or Class B sortase in conjunction with LepA/SipA protein for major pilin polymerization. This observation suggests two distinct modes of sortase-mediated pilus biogenesis in Gram-positive bacteria. Here we review the structural and functional biology of the pilus-sortases from select streptococcal pilus systems and their role in Gram-positive pilus assembly.
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Affiliation(s)
- Baldeep Khare
- Center for Structural Biology, School of Optometry, University of Alabama at Birmingham, Birmingham, USA
| | - Sthanam V L Narayana
- Center for Structural Biology, School of Optometry, University of Alabama at Birmingham, Birmingham, USA
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Lapirattanakul J, Takashima Y, Tantivitayakul P, Maudcheingka T, Leelataweewud P, Nakano K, Matsumoto-Nakano M. Cariogenic properties of Streptococcus mutans clinical isolates with sortase defects. Arch Oral Biol 2017; 81:7-14. [PMID: 28458044 DOI: 10.1016/j.archoralbio.2017.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 02/27/2017] [Accepted: 04/17/2017] [Indexed: 12/30/2022]
Abstract
OBJECTIVE In Streptococcus mutans, a Gram-positive pathogen of dental caries, several surface proteins are anchored by the activity of sortase enzyme. Although various reports have shown that constructed S. mutans mutants deficient of sortase as well as laboratory reference strains with a sortase gene mutation have low cariogenic potential, no known studies have investigated clinical isolates with sortase defects. Here, we examined the cariogenic properties of S. mutans clinical isolates with sortase defects as well as caries status in humans harboring such defective isolates. DESIGN Sortase-defective clinical isolates were evaluated for biofilm formation, sucrose-dependent adhesion, stress-induced dextran-dependent aggregation, acid production, and acid tolerance. Additionally, caries indices of subjects possessing such defective isolates were determined. RESULTS Our in vitro results indicated that biofilm with a lower quantity was formed by sortase-defective as compared to non-defective isolates. Moreover, impairments of sucrose-dependent adhesion and stress-induced dextran-dependent aggregation were found among the isolates with defects, whereas no alterations were seen in regard to acid production or tolerance. Furthermore, glucan-binding protein C, a surface protein anchored by sortase activity, was predominantly detected in culture supernatants of all sortase-defective S. mutans isolates. Although the sortase-defective isolates showed lower cariogenic potential because of a reduction in some cariogenic properties, deft/DMFT indices revealed that all subjects harboring those isolates had caries experience. CONCLUSIONS Our findings suggest the impairment of cariogenic properties in S. mutans clinical isolates with sortase defects, though the detection of these defective isolates seemed not to imply low caries risk in the subjects harboring them.
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Affiliation(s)
- Jinthana Lapirattanakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand.
| | - Yukiko Takashima
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8525, Japan
| | - Pornpen Tantivitayakul
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | - Thaniya Maudcheingka
- Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | | | - Kazuhiko Nakano
- Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, 565-0871, Japan
| | - Michiyo Matsumoto-Nakano
- Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8525, Japan
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Iskandar CF, Borges F, Taminiau B, Daube G, Zagorec M, Remenant B, Leisner JJ, Hansen MA, Sørensen SJ, Mangavel C, Cailliez-Grimal C, Revol-Junelles AM. Comparative Genomic Analysis Reveals Ecological Differentiation in the Genus Carnobacterium. Front Microbiol 2017; 8:357. [PMID: 28337181 PMCID: PMC5341603 DOI: 10.3389/fmicb.2017.00357] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 02/21/2017] [Indexed: 02/01/2023] Open
Abstract
Lactic acid bacteria (LAB) differ in their ability to colonize food and animal-associated habitats: while some species are specialized and colonize a limited number of habitats, other are generalist and are able to colonize multiple animal-linked habitats. In the current study, Carnobacterium was used as a model genus to elucidate the genetic basis of these colonization differences. Analyses of 16S rRNA gene meta-barcoding data showed that C. maltaromaticum followed by C. divergens are the most prevalent species in foods derived from animals (meat, fish, dairy products), and in the gut. According to phylogenetic analyses, these two animal-adapted species belong to one of two deeply branched lineages. The second lineage contains species isolated from habitats where contact with animal is rare. Genome analyses revealed that members of the animal-adapted lineage harbor a larger secretome than members of the other lineage. The predicted cell-surface proteome is highly diversified in C. maltaromaticum and C. divergens with genes involved in adaptation to the animal milieu such as those encoding biopolymer hydrolytic enzymes, a heme uptake system, and biopolymer-binding adhesins. These species also exhibit genes for gut adaptation and respiration. In contrast, Carnobacterium species belonging to the second lineage encode a poorly diversified cell-surface proteome, lack genes for gut adaptation and are unable to respire. These results shed light on the important genomics traits required for adaptation to animal-linked habitats in generalist Carnobacterium.
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Affiliation(s)
- Christelle F. Iskandar
- Laboratoire d’Ingénierie des Biomolécules, École Nationale Supérieure d’Agronomie et des Industries Alimentaires – Université de LorraineVandoeuvre-lès-Nancy, France
| | - Frédéric Borges
- Laboratoire d’Ingénierie des Biomolécules, École Nationale Supérieure d’Agronomie et des Industries Alimentaires – Université de LorraineVandoeuvre-lès-Nancy, France
| | - Bernard Taminiau
- Laboratory of Food Microbiology, Department of Food Science, Fundamental and Applied Research for Animal and Health, University of LiègeLiège, Belgium
| | - Georges Daube
- Laboratory of Food Microbiology, Department of Food Science, Fundamental and Applied Research for Animal and Health, University of LiègeLiège, Belgium
| | | | | | - Jørgen J. Leisner
- Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of CopenhagenFrederiksberg, Denmark
| | - Martin A. Hansen
- Molecular Microbial Ecology Group, University of CopenhagenCopenhagen, Denmark
| | - Søren J. Sørensen
- Molecular Microbial Ecology Group, University of CopenhagenCopenhagen, Denmark
| | - Cécile Mangavel
- Laboratoire d’Ingénierie des Biomolécules, École Nationale Supérieure d’Agronomie et des Industries Alimentaires – Université de LorraineVandoeuvre-lès-Nancy, France
| | - Catherine Cailliez-Grimal
- Laboratoire d’Ingénierie des Biomolécules, École Nationale Supérieure d’Agronomie et des Industries Alimentaires – Université de LorraineVandoeuvre-lès-Nancy, France
| | - Anne-Marie Revol-Junelles
- Laboratoire d’Ingénierie des Biomolécules, École Nationale Supérieure d’Agronomie et des Industries Alimentaires – Université de LorraineVandoeuvre-lès-Nancy, France
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Das S, Pawale VS, Dadireddy V, Singh AK, Ramakumar S, Roy RP. Structure and specificity of a new class of Ca 2+-independent housekeeping sortase from Streptomyces avermitilis provide insights into its non-canonical substrate preference. J Biol Chem 2017; 292:7244-7257. [PMID: 28270507 DOI: 10.1074/jbc.m117.782037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/06/2017] [Indexed: 11/06/2022] Open
Abstract
Surface proteins in Gram-positive bacteria are incorporated into the cell wall through a peptide ligation reaction catalyzed by transpeptidase sortase. Six main classes (A-F) of sortase have been identified of which class A sortase is meant for housekeeping functions. The prototypic housekeeping sortase A (SaSrtA) from Staphylococcus aureus cleaves LPXTG-containing proteins at the scissile T-G peptide bond and ligates protein-LPXT to the terminal Gly residue of the nascent cross-bridge of peptidoglycan lipid II precursor. Sortase-mediated ligation ("sortagging") of LPXTG-containing substrates and Gly-terminated nucleophiles occurs in vitro as well as in cellulo in the presence of Ca2+ and has been applied extensively for protein conjugations. Although the majority of applications emanate from SaSrtA, low catalytic efficiency, LPXTG specificity restriction, and Ca2+ requirement (particularly for in cellulo applications) remain a drawback. Given that Gram-positive bacteria genomes encode a variety of sortases, natural sortase mining can be a viable complementary approach akin to engineering of wild-type SaSrtA. Here, we describe the structure and specificity of a new class E sortase (SavSrtE) annotated to perform housekeeping roles in Streptomyces avermitilis Biochemical experiments define the attributes of an optimum peptide substrate, demonstrate Ca2+-independent activity, and provide insights about contrasting functional characteristics of SavSrtE and SaSrtA. Crystal structure, substrate docking, and mutagenesis experiments have identified a critical residue that dictates the preference for a non-canonical LAXTG recognition motif over LPXTG. These results have implications for rational tailoring of substrate tolerance in sortases. Besides, Ca2+-independent orthogonal specificity of SavSrtE is likely to expand the sortagging toolkit.
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Affiliation(s)
- Sreetama Das
- From the Department of Physics, Indian Institute of Science, Bangalore 560012, and
| | | | | | | | | | - Rajendra P Roy
- the National Institute of Immunology, Delhi 110067, India
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Characterization of the Pathogenicity of Streptococcus intermedius TYG1620 Isolated from a Human Brain Abscess Based on the Complete Genome Sequence with Transcriptome Analysis and Transposon Mutagenesis in a Murine Subcutaneous Abscess Model. Infect Immun 2017; 85:IAI.00886-16. [PMID: 27895128 DOI: 10.1128/iai.00886-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/19/2016] [Indexed: 12/17/2022] Open
Abstract
Streptococcus intermedius is known to cause periodontitis and pyogenic infections in the brain and liver. Here we report the complete genome sequence of strain TYG1620 (genome size, 2,006,877 bp; GC content, 37.6%; 2,020 predicted open reading frames [ORFs]) isolated from a brain abscess in an infant. Comparative analysis of S. intermedius genome sequences suggested that TYG1620 carries a notable type VII secretion system (T7SS), two long repeat regions, and 19 ORFs for cell wall-anchored proteins (CWAPs). To elucidate the genes responsible for the pathogenicity of TYG1620, transcriptome analysis was performed in a murine subcutaneous abscess model. The results suggest that the levels of expression of small hypothetical proteins similar to phenol-soluble modulin β1 (PSMβ1), a staphylococcal virulence factor, significantly increased in the abscess model. In addition, an experiment in a murine subcutaneous abscess model with random transposon (Tn) mutant attenuation suggested that Tn mutants with mutations in 212 ORFs in the Tn mutant library were attenuated in the murine abscess model (629 ORFs were disrupted in total); the 212 ORFs are putatively essential for abscess formation. Transcriptome analysis identified 37 ORFs, including paralogs of the T7SS and a putative glucan-binding CWAP in long repeat regions, to be upregulated and attenuated in vivo This study provides a comprehensive characterization of S. intermedius pathogenicity based on the complete genome sequence and a murine subcutaneous abscess model with transcriptome and Tn mutagenesis, leading to the identification of pivotal targets for vaccines or antimicrobial agents for the control of S. intermedius infections.
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Kattke MD, Chan AH, Duong A, Sexton DL, Sawaya MR, Cascio D, Elliot MA, Clubb RT. Crystal Structure of the Streptomyces coelicolor Sortase E1 Transpeptidase Provides Insight into the Binding Mode of the Novel Class E Sorting Signal. PLoS One 2016; 11:e0167763. [PMID: 27936128 PMCID: PMC5148588 DOI: 10.1371/journal.pone.0167763] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 11/18/2016] [Indexed: 01/17/2023] Open
Abstract
Many species of Gram-positive bacteria use sortase transpeptidases to covalently affix proteins to their cell wall or to assemble pili. Sortase-displayed proteins perform critical and diverse functions for cell survival, including cell adhesion, nutrient acquisition, and morphological development, among others. Based on their amino acid sequences, there are at least six types of sortases (class A to F enzymes); however, class E enzymes have not been extensively studied. Class E sortases are used by soil and freshwater-dwelling Actinobacteria to display proteins that contain a non-canonical LAXTG sorting signal, which differs from 90% of known sorting signals by substitution of alanine for proline. Here we report the first crystal structure of a class E sortase, the 1.93 Å resolution structure of the SrtE1 enzyme from Streptomyces coelicolor. The active site is bound to a tripeptide, providing insight into the mechanism of substrate binding. SrtE1 possesses β3/β4 and β6/β7 active site loops that contact the LAXTG substrate and are structurally distinct from other classes. We propose that SrtE1 and other class E sortases employ a conserved tyrosine residue within their β3/β4 loop to recognize the amide nitrogen of alanine at position P3 of the sorting signal through a hydrogen bond, as seen here. Incapability of hydrogen-bonding with canonical proline-containing sorting signals likely contributes to class E substrate specificity. Furthermore, we demonstrate that surface anchoring of proteins involved in aerial hyphae formation requires an N-terminal segment in SrtE1 that is presumably positioned within the cytoplasm. Combined, our results reveal unique features within class E enzymes that enable them to recognize distinct sorting signals, and could facilitate the development of substrate-based inhibitors of this important enzyme family.
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Affiliation(s)
- Michele D. Kattke
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, United States of America
- Molecular Biology Interdepartmental Program, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Albert H. Chan
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Andrew Duong
- Department of Biology and Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Danielle L. Sexton
- Department of Biology and Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Michael R. Sawaya
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Duilio Cascio
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Marie A. Elliot
- Department of Biology and Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Robert T. Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California, United States of America
- UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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Yin JC, Fei CH, Lo YC, Hsiao YY, Chang JC, Nix JC, Chang YY, Yang LW, Huang IH, Wang S. Structural Insights into Substrate Recognition by Clostridium difficile Sortase. Front Cell Infect Microbiol 2016; 6:160. [PMID: 27921010 PMCID: PMC5118464 DOI: 10.3389/fcimb.2016.00160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 11/07/2016] [Indexed: 01/07/2023] Open
Abstract
Sortases function as cysteine transpeptidases that catalyze the covalent attachment of virulence-associated surface proteins into the cell wall peptidoglycan in Gram-positive bacteria. The substrate proteins targeted by sortase enzymes have a cell wall sorting signal (CWSS) located at the C-terminus. Up to date, it is still not well understood how sortases with structural resemblance among different classes and diverse species of bacteria achieve substrate specificity. In this study, we focus on elucidating the molecular basis for specific recognition of peptide substrate PPKTG by Clostridium difficile sortase B (Cd-SrtB). Combining structural studies, biochemical assays and molecular dynamics simulations, we have constructed a computational model of Cd-SrtBΔN26-PPKTG complex and have validated the model by site-directed mutagensis studies and fluorescence resonance energy transfer (FRET)-based assay. Furthermore, we have revealed that the fourth amino acid in the N-terminal direction from cleavage site of PPKTG forms specific interaction with Cd-SrtB and plays an essential role in configuring the peptide to allow more efficient substrate-specific cleavage by Cd-SrtB.
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Affiliation(s)
- Jui-Chieh Yin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan
| | - Chun-Hsien Fei
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan
| | - Yen-Chen Lo
- Institute of Bioinformatics and Structural Biology, National Tsing Hua UniversityHsinchu, Taiwan,Bioinformatics Program, Taiwan International Graduate Program, Academia SinicaTaipei, Taiwan
| | - Yu-Yuan Hsiao
- Department of Biological Science and Technology, National Chiao Tung UniversityHsinchu, Taiwan
| | - Jyun-Cyuan Chang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan
| | - Jay C. Nix
- Molecular Biology Consortium, Advanced Light Source, Lawrence Berkeley National LaboratoryBerkeley, CA, USA
| | - Yuan-Yu Chang
- Institute of Bioinformatics and Structural Biology, National Tsing Hua UniversityHsinchu, Taiwan
| | - Lee-Wei Yang
- Institute of Bioinformatics and Structural Biology, National Tsing Hua UniversityHsinchu, Taiwan,Physics Division, National Center for Theoretical SciencesHsinchu, Taiwan,*Correspondence: Lee-Wei Yang
| | - I-Hsiu Huang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung UniversityTainan, Taiwan,I-Hsiu Huang
| | - Shuying Wang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung UniversityTainan, Taiwan,Center of Infectious Disease and Signaling Research, National Cheng Kung UniversityTainan, Taiwan,Shuying Wang
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39
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Jacobitz AW, Naziga EB, Yi SW, McConnell SA, Peterson R, Jung ME, Clubb RT, Wereszczynski J. The "Lid" in the Streptococcus pneumoniae SrtC1 Sortase Adopts a Rigid Structure that Regulates Substrate Access to the Active Site. J Phys Chem B 2016; 120:8302-12. [PMID: 27109553 DOI: 10.1021/acs.jpcb.6b01930] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Many species of Gram-positive bacteria use sortase enzymes to assemble long, proteinaceous pili structures that project from the cell surface to mediate microbial adhesion. Sortases construct highly stable structures by catalyzing a transpeptidation reaction that covalently links pilin subunits together via isopeptide bonds. Most Gram-positive pili are assembled by class C sortases that contain a "lid", a structurally unique N-terminal extension that occludes the active site. It has been hypothesized that the "lid" in many sortases is mobile and thus capable of readily being displaced from the enzyme to facilitate substrate binding. Here, we show using NMR dynamics measurements, in vitro assays, and molecular dynamics simulations that the lid in the class C sortase from Streptococcus pneumoniae (SrtC1) adopts a rigid conformation in solution that is devoid of large magnitude conformational excursions that occur on mechanistically relevant time scales. Additionally, we show that point mutations in the lid induce dynamic behavior that correlates with increased hydrolytic activity and sorting signal substrate access to the active site cysteine residue. These results suggest that the lid of the S. pneumoniae SrtC1 enzyme has a negative regulatory function and imply that a significant energetic barrier must be surmounted by currently unidentified factors to dislodge it from the active site to initiate pilus biogenesis.
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Affiliation(s)
- Alex W Jacobitz
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Emmanuel B Naziga
- Department of Physics and Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology , 3440 South Dearborn Street, Chicago, Illinois 60616, United States
| | - Sung Wook Yi
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Scott A McConnell
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Robert Peterson
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Michael E Jung
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Robert T Clubb
- Department of Chemistry and Biochemistry and the UCLA-DOE Institute of Genomics and Proteomics, University of California, Los Angeles , 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, United States
| | - Jeff Wereszczynski
- Department of Physics and Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology , 3440 South Dearborn Street, Chicago, Illinois 60616, United States
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40
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Douillard FP, Rasinkangas P, Bhattacharjee A, Palva A, de Vos WM. The N-Terminal GYPSY Motif Is Required for Pilin-Specific Sortase SrtC1 Functionality in Lactobacillus rhamnosus Strain GG. PLoS One 2016; 11:e0153373. [PMID: 27070897 PMCID: PMC4829219 DOI: 10.1371/journal.pone.0153373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/29/2016] [Indexed: 12/31/2022] Open
Abstract
Predominantly identified in pathogenic Gram-positive bacteria, sortase-dependent pili are also found in commensal species, such as the probiotic-marketed strain Lactobacillus rhamnosus strain GG. Pili are typically associated with host colonization, immune signalling and biofilm formation. Comparative analysis of the N-terminal domains of pilin-specific sortases from various piliated Gram-positive bacteria identified a conserved motif, called GYPSY, within the signal sequence. We investigated the function and role of the GYPSY residues by directed mutagenesis in homologous (rod-shaped) and heterologous (coccoid-shaped) expression systems for pilus formation. Substitutions of some of the GYPSY residues, and more specifically the proline residue, were found to have a direct impact on the degree of piliation of Lb. rhamnosus GG. The present findings uncover a new signalling element involved in the functionality of pilin-specific sortases controlling the pilus biogenesis of Lb. rhamnosus GG and related piliated Gram-positive species.
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Affiliation(s)
- François P. Douillard
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- * E-mail: (FPD); (WMdV)
| | - Pia Rasinkangas
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Arnab Bhattacharjee
- Research Programs Unit Immunobiology, Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - Airi Palva
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Willem M. de Vos
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Research Programs Unit Immunobiology, Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
- * E-mail: (FPD); (WMdV)
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41
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Richards L, Li M, van Esch B, Garssen J, Folkerts G. The effects of short-chain fatty acids on the cardiovascular system. PHARMANUTRITION 2016. [DOI: 10.1016/j.phanu.2016.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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42
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Spatial Organization of Cell Wall-Anchored Proteins at the Surface of Gram-Positive Bacteria. Curr Top Microbiol Immunol 2016; 404:177-201. [DOI: 10.1007/82_2016_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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43
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Chan AH, Yi SW, Terwilliger AL, Maresso AW, Jung ME, Clubb RT. Structure of the Bacillus anthracis Sortase A Enzyme Bound to Its Sorting Signal: A FLEXIBLE AMINO-TERMINAL APPENDAGE MODULATES SUBSTRATE ACCESS. J Biol Chem 2015; 290:25461-74. [PMID: 26324714 DOI: 10.1074/jbc.m115.670984] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Indexed: 12/31/2022] Open
Abstract
The endospore forming bacterium Bacillus anthracis causes lethal anthrax disease in humans and animals. The ability of this pathogen to replicate within macrophages is dependent upon the display of bacterial surface proteins attached to the cell wall by the B. anthracis Sortase A ((Ba)SrtA) enzyme. Previously, we discovered that the class A (Ba)SrtA sortase contains a unique N-terminal appendage that wraps around the body of the protein to contact the active site of the enzyme. To gain insight into its function, we determined the NMR structure of (Ba)SrtA bound to a LPXTG sorting signal analog. The structure, combined with dynamics, kinetics, and whole cell protein display data suggest that the N terminus modulates substrate access to the enzyme. We propose that it may increase the efficiency of protein display by reducing the unproductive hydrolytic cleavage of enzyme-protein covalent intermediates that form during the cell wall anchoring reaction. Notably, a key active site loop (β7/β8 loop) undergoes a disordered to ordered transition upon binding the sorting signal, potentially facilitating recognition of lipid II.
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Affiliation(s)
- Albert H Chan
- From the Department of Chemistry and Biochemistry, UCLA-DOE Institute of Genomics and Proteomics, and the Molecular Biology Institute, University of California, Los Angeles, California 90095 and
| | - Sung Wook Yi
- From the Department of Chemistry and Biochemistry
| | - Austen L Terwilliger
- the Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030
| | - Anthony W Maresso
- the Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030
| | | | - Robert T Clubb
- From the Department of Chemistry and Biochemistry, UCLA-DOE Institute of Genomics and Proteomics, and the Molecular Biology Institute, University of California, Los Angeles, California 90095 and
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44
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Bradshaw WJ, Davies AH, Chambers CJ, Roberts AK, Shone CC, Acharya KR. Molecular features of the sortase enzyme family. FEBS J 2015; 282:2097-114. [PMID: 25845800 DOI: 10.1111/febs.13288] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 03/13/2015] [Accepted: 03/28/2015] [Indexed: 01/31/2023]
Abstract
Bacteria possess complex and varying cell walls with many surface exposed proteins. Sortases are responsible for the covalent attachment of specific proteins to the peptidoglycan of the cell wall of Gram-positive bacteria. Sortase A of Staphylococcus aureus, which is seen as the archetypal sortase, has been shown to be essential for pathogenesis and has therefore received much attention as a potential target for novel therapeutics. Being widely present in Gram-positive bacteria, it is likely that other Gram-positive pathogens also require sortases for their pathogenesis. Sortases have also been shown to be of significant use in a range of industrial applications. We review current knowledge of the sortase family in terms of their structures, functions and mechanisms and summarize work towards their use as antibacterial targets and microbiological tools.
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Affiliation(s)
- William J Bradshaw
- Department of Biology and Biochemistry, University of Bath, UK.,Public Health England, Porton Down, Salisbury, UK
| | | | - Christopher J Chambers
- Department of Biology and Biochemistry, University of Bath, UK.,Public Health England, Porton Down, Salisbury, UK
| | | | | | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, UK
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45
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Structure and function of a Clostridium difficile sortase enzyme. Sci Rep 2015; 5:9449. [PMID: 25801974 PMCID: PMC4371152 DOI: 10.1038/srep09449] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 03/05/2015] [Indexed: 01/20/2023] Open
Abstract
Sortase enzymes are responsible for covalent anchoring of specific proteins to the peptidoglycan of the cell wall of gram-positive bacteria. In some gram-positive bacteria (e.g. Staphylococcus aureus), sortases have been found to be essential for pathogenesis and their inhibitors are under development as potential novel therapeutics. Here we provide the first report on the structural characterisation of the C. difficile sortase. An active site mutant was crystallised and its structure determined to 2.55 Å by X-ray diffraction to provide structural insight into its catalytic mechanism. In order to elucidate the role of the sortase in the cell wall biogenesis, a C. difficile sortase knockout strain was constructed by intron mutagenesis. Characterisation of this mutant led to the discovery that the putative adhesin CD0386 is anchored to the peptidoglycan of C. difficile by the sortase SrtB and that an SPKTG peptide motif is involved in the transpeptidation reaction with the C. difficile peptidoglycan. In an animal model for C. difficile infection, the SrtB mutant caused disease at a similar rate of onset as the wild type strain. In conclusion, our detailed study shows that the SrtB enzyme from C. difficile does not play an essential role in pathogenesis.
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46
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Abstract
Pili of Gram-positive bacteria are unique structures on the bacterial surface, assembled from covalently linked polypeptide subunits. Pilus assembly proceeds by transpeptidation reactions catalyzed by sortases, followed by covalent anchoring of the filament in the peptidoglycan layer. Another distinctive property is the presence of intramolecular isopeptide bonds, conferring extraordinary chemical and mechanical stability to these elongated structures. Besides their function in cell adhesion and biofilm formation, this section discusses possible application of pilus constituents as vaccine components against Gram-positive pathogens.
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47
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Cockburn DW, Orlovsky NI, Foley MH, Kwiatkowski KJ, Bahr CM, Maynard M, Demeler B, Koropatkin NM. Molecular details of a starch utilization pathway in the human gut symbiont Eubacterium rectale. Mol Microbiol 2015; 95:209-30. [PMID: 25388295 PMCID: PMC4437465 DOI: 10.1111/mmi.12859] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2014] [Indexed: 01/07/2023]
Abstract
Eubacterium rectale is a prominent human gut symbiont yet little is known about the molecular strategies this bacterium has developed to acquire nutrients within the competitive gut ecosystem. Starch is one of the most abundant glycans in the human diet, and E. rectale increases in vivo when the host consumes a diet rich in resistant starch, although it is not a primary degrader of this glycan. Here we present the results of a quantitative proteomics study in which we identify two glycoside hydrolase 13 family enzymes, and three ABC transporter solute-binding proteins that are abundant during growth on starch and, we hypothesize, work together at the cell surface to degrade starch and capture the released maltooligosaccharides. EUR_21100 is a multidomain cell wall anchored amylase that preferentially targets starch polysaccharides, liberating maltotetraose, whereas the membrane-associated maltogenic amylase EUR_01860 breaks down maltooligosaccharides longer than maltotriose. The three solute-binding proteins display a range of glycan-binding specificities that ensure the capture of glucose through maltoheptaose and some α1,6-branched glycans. Taken together, we describe a pathway for starch utilization by E. rectale DSM 17629 that may be conserved among other starch-degrading Clostridium cluster XIVa organisms in the human gut.
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Affiliation(s)
- Darrell W. Cockburn
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Nicole I. Orlovsky
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Matthew H. Foley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Kurt J. Kwiatkowski
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Constance M. Bahr
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Mallory Maynard
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Borries Demeler
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, TX 78229
| | - Nicole M. Koropatkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
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48
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Biology and Assembly of the Bacterial Envelope. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 883:41-76. [PMID: 26621461 DOI: 10.1007/978-3-319-23603-2_3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
All free-living bacterial cells are delimited and protected by an envelope of high complexity. This physiological barrier is essential for bacterial survival and assures multiple functions. The molecular assembly of the different envelope components into a functional structure represents a tremendous biological challenge and is of high interest for fundamental sciences. The study of bacterial envelope assembly has also been fostered by the need for novel classes of antibacterial agents to fight the problematic of bacterial resistance to antibiotics. This chapter focuses on the two most intensively studied classes of bacterial envelopes that belong to the phyla Firmicutes and Proteobacteria. The envelope of Firmicutes typically has one membrane and is defined as being monoderm whereas the envelope of Proteobacteria contains two distinct membranes and is referred to as being diderm. In this chapter, we will first discuss the multiple roles of the bacterial envelope and clarify the nomenclature used to describe the different types of envelopes. We will then define the architecture and composition of the envelopes of Firmicutes and Proteobacteria while outlining their similarities and differences. We will further cover the extensive progress made in the field of bacterial envelope assembly over the last decades, using Bacillus subtilis and Escherichia coli as model systems for the study of the monoderm and diderm bacterial envelopes, respectively. We will detail our current understanding of how molecular machines assure the secretion, insertion and folding of the envelope proteins as well as the assembly of the glycosidic components of the envelope. Finally, we will highlight the topics that are still under investigation, and that will surely lead to important discoveries in the near future.
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49
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Cascioferro S, Totsika M, Schillaci D. Sortase A: An ideal target for anti-virulence drug development. Microb Pathog 2014; 77:105-12. [DOI: 10.1016/j.micpath.2014.10.007] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 10/08/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
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50
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Amer BR, Clubb RT. A sweet new role for LCP enzymes in protein glycosylation. Mol Microbiol 2014; 94:1197-200. [PMID: 25302626 DOI: 10.1111/mmi.12825] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2014] [Indexed: 11/26/2022]
Abstract
The peptidoglycan that surrounds Gram-positive bacteria is affixed with a range of macromolecules that enable the microbe to effectively interact with its environment. Distinct enzymes decorate the cell wall with proteins and glycopolymers. Sortase enzymes covalently attach proteins to the peptidoglycan, while LytR-CpsA-Psr (LCP) proteins are thought to attach teichoic acid polymers and capsular polysaccharides. Ton-That and colleagues have discovered a new glycosylation pathway in the oral bacterium Actinomyces oris in which sortase and LCP enzymes operate on the same protein substrate. The A. oris LCP protein has a novel function, acting on the cell surface to transfer glycan macromolecules to a protein, which is then attached to the cell wall by a sortase. The reactions are tightly coupled, as elimination of the sortase causes the lethal accumulation of glycosylated protein in the membrane. Since sortase enzymes are attractive drug targets, this novel finding may provide a convenient cell-based tool to discover inhibitors of this important enzyme family.
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Affiliation(s)
- Brendan R Amer
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA, 90095, USA
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