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Prusty JS, Kumar A. LC-MS/MS profiling and analysis of Bacillus licheniformis extracellular proteins for antifungal potential against Candida albicans. J Proteomics 2024; 303:105228. [PMID: 38878881 DOI: 10.1016/j.jprot.2024.105228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 06/18/2024]
Abstract
Candida albicans, a significant human pathogenic fungus, employs hydrolytic proteases for host invasion. Conventional antifungal agents are reported with resistance issues from around the world. This study investigates the role of Bacillus licheniformis extracellular proteins (ECP) as effective antifungal peptides (AFPs). The aim was to identify and characterize the ECP of B. licheniformis through LC-MS/MS and bioinformatics analysis. LC-MS/MS analysis identified 326 proteins with 69 putative ECP, further analyzed in silico. Of these, 21 peptides exhibited antifungal properties revealed by classAMP tool and are predominantly anionic. Peptide-protein docking revealed interactions between AFPs like Peptide chain release factor 1 (Q65DV1_Seq1: SASEQLSDAK) and Putative carboxy peptidase (Q65IF0_Seq7: SDSSLEDQDFILESK) with C. albicans virulent SAP5 proteins (PDB ID 2QZX), forming hydrogen bonds and significant Pi-Pi interactions. The identification of B. licheniformis ECP is the novelty of the study that sheds light on their antifungal potential. The identified AFPs, particularly those interacting with bonafide pharmaceutical targets SAP5 of C. albicans represent promising avenues for the development of antifungal treatments with AFPs that could be the pursuit of a novel therapeutic strategy against C. albicans. SIGNIFICANCE OF STUDY: The purpose of this work was to carry out proteomic profiling of the secretome of B. licheniformis. Previously, the efficacy of Bacillus licheniformis extracellular proteins against Candida albicans was investigated and documented in a recently communicated manuscript, showcasing the antifungal activity of these proteins. In order to achieve high-throughput identification of ES (Excretory-secretory) proteins, the utilization of liquid chromatography tandem mass spectrometry (LC-MS) was utilized. There was a lack of comprehensive research on AFPs in B. licheniformis, nevertheless. The proteins secreted by B. licheniformis in liquid medium were initially discovered using liquid chromatography-tandem mass spectrometry (LC-MS) analysis and identification in order to immediately characterize the unidentified active metabolites in fermentation broth.
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Affiliation(s)
- Jyoti Sankar Prusty
- Department of Biotechnology, National Institute of Technology, Raipur 492010, CG, India
| | - Awanish Kumar
- Department of Biotechnology, National Institute of Technology, Raipur 492010, CG, India.
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2
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Kumari K, Dey J, Mahapatra SR, Ma Y, Sharma PK, Misra N, Singh RP. Protein profiling and immunoinformatic analysis of the secretome of a metal-resistant environmental isolate Pseudomonas aeruginosa S-8. Folia Microbiol (Praha) 2024:10.1007/s12223-024-01152-5. [PMID: 38457114 DOI: 10.1007/s12223-024-01152-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 02/03/2024] [Indexed: 03/09/2024]
Abstract
The bacterial secretome represents a comprehensive catalog of proteins released extracellularly that have multiple important roles in virulence and intercellular communication. This study aimed to characterize the secretome of an environmental isolate Pseudomonas aeruginosa S-8 by analyzing trypsin-digested culture supernatant proteins using nano-LC-MS/MS tool. Using a combined approach of bioinformatics and mass spectrometry, 1088 proteins in the secretome were analyzed by PREDLIPO, SecretomeP 2.0, SignalP 4.1, and PSORTb tool for their subcellular localization and further categorization of secretome proteins according to signal peptides. Using the gene ontology tool, secretome proteins were categorized into different functional categories. KEGG pathway analysis identified the secreted proteins into different metabolic functional pathways. Moreover, our LC-MS/MS data revealed the secretion of various CAZymes into the extracellular milieu, which suggests its strong biotechnological applications to breakdown complex carbohydrate polymers. The identified immunodominant epitopes from the secretome of P. aeruginosa showed the characteristic of being non-allergenic, highly antigenic, nontoxic, and having a low risk of triggering autoimmune responses, which highlights their potential as successful vaccine targets. Overall, the identification of secreted proteins of P. aeruginosa could be important for both diagnostic purposes and the development of an effective candidate vaccine.
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Affiliation(s)
- Kiran Kumari
- Department of Bioengineering and Biotechnology, Birla Institute of Technology, Ranchi, 835215, India
| | - Jyotirmayee Dey
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Soumya Ranjan Mahapatra
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Ying Ma
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Parva Kumar Sharma
- Department of Plant Sciences and Landscape Architecture, University of Maryland, College Park, MD, 20742, USA
| | - Namrata Misra
- School of Biotechnology, Deemed to Be University, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, 751024, India
| | - Rajnish Prakash Singh
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, 201309, India.
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3
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Abbasi BA, Dharan A, Mishra A, Saraf D, Ahamad I, Suravajhala P, Valadi J. In Silico Characterization of Uncharacterized Proteins From Multiple Strains of Clostridium Difficile. Front Genet 2022; 13:878012. [PMID: 36035185 PMCID: PMC9403866 DOI: 10.3389/fgene.2022.878012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 06/22/2022] [Indexed: 11/13/2022] Open
Abstract
Clostridium difficile (C. difficile) is a multi-strain, spore-forming, Gram-positive, opportunistic enteropathogen bacteria, majorly associated with nosocomial infections, resulting in severe diarrhoea and colon inflammation. Several antibiotics including penicillin, tetracycline, and clindamycin have been employed to control C. difficile infection, but studies have suggested that injudicious use of antibiotics has led to the development of resistance in C. difficile strains. However, many proteins from its genome are still considered uncharacterized proteins that might serve crucial functions and assist in the biological understanding of the organism. In this study, we aimed to annotate and characterise the 6 C. difficile strains using in silico approaches. We first analysed the complete genome of 6 C. difficile strains using standardised approaches and analysed hypothetical proteins (HPs) employing various bioinformatics approaches coalescing, including identifying contigs, coding sequences, phage sequences, CRISPR-Cas9 systems, antimicrobial resistance determination, membrane helices, instability index, secretory nature, conserved domain, and vaccine target properties like comparative homology analysis, allergenicity, antigenicity determination along with structure prediction and binding-site analysis. This study provides crucial supporting information about the functional characterization of the HPs involved in the pathophysiology of the disease. Moreover, this information also aims to assist in mechanisms associated with bacterial pathogenesis and further design candidate inhibitors and bona fide pharmaceutical targets.
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Affiliation(s)
| | | | | | | | | | - Prashanth Suravajhala
- Bioclues.org, Hyderabad, India
- Amrita School of Biotechnology, Amrita Vishwa Vidyapeetham, Clappana, India
- *Correspondence: Prashanth Suravajhala, ; Jayaraman Valadi,
| | - Jayaraman Valadi
- Bioclues.org, Hyderabad, India
- School of Computational and Data Sciences, Vidyashilp University, Bengaluru, India
- Department of Computer Science, FLAME University, Pune, India
- *Correspondence: Prashanth Suravajhala, ; Jayaraman Valadi,
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4
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A noncanonical chaperone interacts with drug efflux pumps during their assembly into bacterial outer membranes. PLoS Biol 2022; 20:e3001523. [PMID: 35061668 PMCID: PMC8809574 DOI: 10.1371/journal.pbio.3001523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 02/02/2022] [Accepted: 12/22/2021] [Indexed: 11/19/2022] Open
Abstract
Bacteria have membrane-spanning efflux pumps to secrete toxic compounds ranging from heavy metal ions to organic chemicals, including antibiotic drugs. The overall architecture of these efflux pumps is highly conserved: with an inner membrane energy-transducing subunit coupled via an adaptor protein to an outer membrane conduit subunit that enables toxic compounds to be expelled into the environment. Here, we map the distribution of efflux pumps across bacterial lineages to show these proteins are more widespread than previously recognised. Complex phylogenetics support the concept that gene cassettes encoding the subunits for these pumps are commonly acquired by horizontal gene transfer. Using TolC as a model protein, we demonstrate that assembly of conduit subunits into the outer membrane uses the chaperone TAM to physically organise the membrane-embedded staves of the conduit subunit of the efflux pump. The characteristics of this assembly pathway have impact for the acquisition of efflux pumps across bacterial species and for the development of new antimicrobial compounds that inhibit efflux pump function. A crosslinking study reveals novel insights into how the chaperone TAM helps Gram-negative bacteria insert the drug efflux pump subunit TolC into their outer membrane. Bioinformatic analyses show that TolC-like proteins can be found in all LPS-containing bacteria, but also in some monodermic Firmicutes.
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Vieira KCDO, Silva HRAD, Rocha IPM, Barboza E, Eller LKW. Foodborne pathogens in the omics era. Crit Rev Food Sci Nutr 2021; 62:6726-6741. [PMID: 33783282 DOI: 10.1080/10408398.2021.1905603] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Outbreaks and deaths related to Foodborne Diseases (FBD) occur constantly in the world, as a result of the consumption of contaminated foodstuffs with pathogens such as Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, Salmonella spp, Clostridium spp. and Campylobacter spp. The purpose of this review is to discuss the main omic techniques applied in foodborne pathogen and to demonstrate their functionalities through the food chain and to guarantee the food safety. The main techniques presented are genomic, transcriptomic, secretomic, proteomic, and metabolomic, which together, in the field of food and nutrition, are known as "Foodomics." This review had highlighted the potential of omics to integrate variables that contribute to food safety and to enable us to understand their application on foodborne diseases. The appropriate use of these techniques had driven the definition of critical parameters to achieve successful results in the improvement of consumers health, costs and to obtain safe and high-quality products.
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Affiliation(s)
| | | | | | - Emmanuel Barboza
- Health Sciences Faculty, University of Western Sao Paulo, Presidente Prudente, Sao Paulo, Brazil
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Engevik MA, Danhof HA, Chang-Graham AL, Spinler JK, Engevik KA, Herrmann B, Endres BT, Garey KW, Hyser JM, Britton RA, Versalovic J. Human intestinal enteroids as a model of Clostridioides difficile-induced enteritis. Am J Physiol Gastrointest Liver Physiol 2020; 318:G870-G888. [PMID: 32223302 PMCID: PMC7272722 DOI: 10.1152/ajpgi.00045.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Clostridioides difficile is an important nosocomial pathogen that produces toxins to cause life-threatening diarrhea and colitis. Toxins bind to epithelial receptors and promote the collapse of the actin cytoskeleton. C. difficile toxin activity is commonly studied in cancer-derived and immortalized cell lines. However, the biological relevance of these models is limited. Moreover, no model is available for examining C. difficile-induced enteritis, an understudied health problem. We hypothesized that human intestinal enteroids (HIEs) express toxin receptors and provide a new model to dissect C. difficile cytotoxicity in the small intestine. We generated biopsy-derived jejunal HIE and Vero cells, which stably express LifeAct-Ruby, a fluorescent label of F-actin, to monitor actin cytoskeleton rearrangement by live-cell microscopy. Imaging analysis revealed that toxins from pathogenic C. difficile strains elicited cell rounding in a strain-dependent manner, and HIEs were tenfold more sensitive to toxin A (TcdA) than toxin B (TcdB). By quantitative PCR, we paradoxically found that HIEs expressed greater quantities of toxin receptor mRNA and yet exhibited decreased sensitivity to toxins when compared with traditionally used cell lines. We reasoned that these differences may be explained by components, such as mucins, that are present in HIEs cultures, that are absent in immortalized cell lines. Addition of human-derived mucin 2 (MUC2) to Vero cells delayed cell rounding, indicating that mucus serves as a barrier to toxin-receptor binding. This work highlights that investigation of C. difficile infection in that HIEs can provide important insights into the intricate interactions between toxins and the human intestinal epithelium.NEW & NOTEWORTHY In this article, we developed a novel model of Clostridioides difficile-induced enteritis using jejunal-derived human intestinal enteroids (HIEs) transduced with fluorescently tagged F-actin. Using live-imaging, we identified that jejunal HIEs express high levels of TcdA and CDT receptors, are more sensitive to TcdA than TcdB, and secrete mucus, which delays toxin-epithelial interactions. This work also optimizes optically clear C. difficile-conditioned media suitable for live-cell imaging.
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Affiliation(s)
- Melinda A. Engevik
- 1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas,2Department of Pathology, Texas Children’s Hospital, Houston, Texas
| | - Heather A. Danhof
- 3Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, Texas,4Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas
| | | | - Jennifer K. Spinler
- 1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas,2Department of Pathology, Texas Children’s Hospital, Houston, Texas
| | - Kristen A. Engevik
- 3Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, Texas,4Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas
| | - Beatrice Herrmann
- 1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas,2Department of Pathology, Texas Children’s Hospital, Houston, Texas
| | - Bradley T. Endres
- 5Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas
| | - Kevin W. Garey
- 5Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas
| | - Joseph M. Hyser
- 1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas,2Department of Pathology, Texas Children’s Hospital, Houston, Texas
| | - Robert A. Britton
- 3Alkek Center for Metagenomic and Microbiome Research, Baylor College of Medicine, Houston, Texas,4Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas
| | - James Versalovic
- 1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas,2Department of Pathology, Texas Children’s Hospital, Houston, Texas
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Quesada-Gómez C, Murillo T, Arce G, Badilla-Lobo A, Castro-Peña C, Molina J, López-Ureña D, González-Camacho S, Lomonte B, Chacón-Díaz C, Rodríguez C, Chaves-Olarte E. Proteogenomic analysis of the Clostridium difficile exoproteome reveals a correlation between phylogenetic distribution and virulence potential. Anaerobe 2020; 62:102151. [DOI: 10.1016/j.anaerobe.2020.102151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 12/28/2019] [Accepted: 01/10/2020] [Indexed: 12/16/2022]
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8
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Progresses on bacterial secretomes enlighten research on Mycoplasma secretome. Microb Pathog 2020; 144:104160. [PMID: 32194181 DOI: 10.1016/j.micpath.2020.104160] [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: 02/19/2020] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 11/20/2022]
Abstract
Bacterial secretome is a comprehensive catalog of bacterial proteins that are released or secreted outside the cells. They offer a number of factors that possess several significant roles in virulence as well as cell to cell communication and hence play a core role in bacterial pathogenesis. Sometimes these proteins are bounded with membranes giving them the shape of vesicles called extracellular vesicles (EVs) or outer membrane vesicles (OMVs). Bacteria secrete these proteins via Sec and Tat pathways into the periplasm. Secreted proteins have found to be important as diagnostic markers as well as antigenic factors for the development of an effective candidate vaccine. Recently, the research in the field of secretomics is growing up and getting more interesting due to their direct involvement in the pathogenesis of the microorganisms leading to the infection. Many pathogenic bacteria have been studied for their secretome and the results illustrated novel antigens. This review highlights the secretome studies of different pathogenic bacteria in humans and animals, general secretion mechanisms, different approaches and challenges in the secretome of Mycoplasma sp.
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Dresler J, Krutova M, Fucikova A, Klimentova J, Hruzova V, Duracova M, Houdkova K, Salovska B, Matejkova J, Hubalek M, Pajer P, Pisa L, Nyc O. Analysis of proteomes released from in vitro cultured eight Clostridium difficile PCR ribotypes revealed specific expression in PCR ribotypes 027 and 176 confirming their genetic relatedness and clinical importance at the proteomic level. Gut Pathog 2017; 9:45. [PMID: 28814976 PMCID: PMC5556371 DOI: 10.1186/s13099-017-0194-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/28/2017] [Indexed: 01/22/2023] Open
Abstract
Background Clostridium difficile is the causative agent of C. difficile infection (CDI) that could be manifested by diarrhea, pseudomembranous colitis or life-threatening toxic megacolon. The spread of certain strains represents a significant economic burden for health-care. The epidemic successful strains are also associated with severe clinical features of CDI. Therefore, a proteomic study has been conducted that comprises proteomes released from in vitro cultured panel of eight different PCR ribotypes (RTs) and employs the combination of shotgun proteomics and label-free quantification (LFQ) approach. Results The comparative semi-quantitative analyses enabled investigation of a total of 662 proteins. Both hierarchical clustering and principal component analysis (PCA) created eight distinctive groups. From these quantifiable proteins, 27 were significantly increased in functional annotations. Among them, several known factors connected with virulence were identified, such as toxin A, B, binary toxin, flagellar proteins, and proteins associated with Pro–Pro endopeptidase (PPEP-1) functional complex. Comparative analysis of protein expression showed a higher expression or unique expression of proteins linked to pathogenicity or iron metabolism in RTs 027 and 176 supporting their genetic relatedness and clinical importance at the proteomic level. Moreover, the absence of putative nitroreductase and the abundance of the Abc-type fe3+ transport system protein were observed as biomarkers for the RTs possessing binary toxin genes (027, 176 and 078). Higher expression of selected flagellar proteins clearly distinguished RTs 027, 176, 005 and 012, confirming the pathogenic role of the assembly in CDI. Finally, the histidine synthesis pathway regulating protein complex HisG/HisZ was observed only in isolates possessing the genes for toxin A and B. Conclusions This study showed the applicability of the LFQ approach and provided the first semi-quantitative insight into the proteomes released from in vitro cultured panel of eight RTs. The observed differences pointed to a new direction for studies focused on the elucidation of the mechanisms underlining the CDI nature. Electronic supplementary material The online version of this article (doi:10.1186/s13099-017-0194-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiri Dresler
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Marcela Krutova
- Department of Medical Microbiology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
| | - Alena Fucikova
- Faculty of Military Health Sciences, UoD, Hradec Kralove, Czech Republic
| | - Jana Klimentova
- Faculty of Military Health Sciences, UoD, Hradec Kralove, Czech Republic
| | - Veronika Hruzova
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Miloslava Duracova
- Faculty of Military Health Sciences, UoD, Hradec Kralove, Czech Republic
| | - Katerina Houdkova
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Barbora Salovska
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Jana Matejkova
- Department of Medical Microbiology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
| | - Martin Hubalek
- Institute of Organic Chemistry and Biochemistry, Academy of Science, Prague, Czech Republic
| | - Petr Pajer
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Libor Pisa
- Military Health Institute, Military Medical Agency, Tychonova 1, Prague, Czech Republic
| | - Otakar Nyc
- Department of Medical Microbiology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
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10
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Ferreira TG, Moura H, Barr JR, Pilotto Domingues RMC, Ferreira EDO. Ribotypes associated with Clostridium difficile outbreaks in Brazil display distinct surface protein profiles. Anaerobe 2017; 45:120-128. [PMID: 28435010 DOI: 10.1016/j.anaerobe.2017.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/28/2017] [Accepted: 04/01/2017] [Indexed: 11/18/2022]
Abstract
Clostridium difficile is a spore-forming anaerobic intestinal pathogen that causes Clostridium difficile infection (CDI). C. difficile is the leading cause of toxin-mediated nosocomial antibiotic-associated diarrhea. The pathogenesis of CDI is attributed to two major virulence factors, TcdA and TcdB toxins, that cause the symptomatic infection. C. difficile also expresses a number of key proteins, including cell wall proteins (CWPs). S-layer proteins (SLPs) are CWPs that form a paracrystalline surface array that coats the surface of the bacterium. SLPs have a role in C. difficile binding to the gastrointestinal tract, but their importance in virulence need to be better elucidated. Here, we describe bottom-up proteomics analysis of surface-enriched proteins fractions obtained through glycine extraction of five C. difficile clinical isolates from Brazil using gel-based and gel-free approaches. We were able to identify approximately 250 proteins for each strain, among them SlpA, Cwp2, Cwp6, CwpV and Cwp84. Identified CWPs presented different amino acid coverage, which might suggest differences in post-translational modifications. Proteomic analysis of SLPs from ribotype 133, agent of C. difficile outbreaks in Brazil, revealed unique proteins and provided additional information towards in depth characterization of the strains causing CDI in Brazil.
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Affiliation(s)
- Thais Gonçalves Ferreira
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, Brazil
| | - Hercules Moura
- Centers for Disease Control and Prevention - CDC, Division of Laboratory Sciences, Atlanta, GA, USA
| | - John R Barr
- Centers for Disease Control and Prevention - CDC, Division of Laboratory Sciences, Atlanta, GA, USA
| | - Regina M C Pilotto Domingues
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, Brazil.
| | - Eliane de Oliveira Ferreira
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, Brazil; Universidade Federal do Rio de Janeiro - Polo Xerém, Rio de Janeiro, Brazil
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Marshall NC, Finlay BB, Overall CM. Sharpening Host Defenses during Infection: Proteases Cut to the Chase. Mol Cell Proteomics 2017; 16:S161-S171. [PMID: 28179412 PMCID: PMC5393396 DOI: 10.1074/mcp.o116.066456] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/03/2017] [Indexed: 01/14/2023] Open
Abstract
The human immune system consists of an intricate network of tightly controlled pathways, where proteases are essential instigators and executioners at multiple levels. Invading microbial pathogens also encode proteases that have evolved to manipulate and dysregulate host proteins, including host proteases during the course of disease. The identification of pathogen proteases as well as their substrates and mechanisms of action have empowered significant developments in therapeutics for infectious diseases. Yet for many pathogens, there remains a great deal to be discovered. Recently, proteomic techniques have been developed that can identify proteolytically processed proteins across the proteome. These “degradomics” approaches can identify human substrates of microbial proteases during infection in vivo and expose the molecular-level changes that occur in the human proteome during infection as an operational network to develop hypotheses for further research as well as new therapeutics. This Perspective Article reviews how proteases are utilized during infection by both the human host and invading bacterial pathogens, including archetypal virulence-associated microbial proteases, such as the Clostridia spp. botulinum and tetanus neurotoxins. We highlight the potential knowledge that degradomics studies of host–pathogen interactions would uncover, as well as how degradomics has been successfully applied in similar contexts, including use with a viral protease. We review how microbial proteases have been targeted in current therapeutic approaches and how microbial proteases have shaped and even contributed to human therapeutics beyond infectious disease. Finally, we discuss how, moving forward, degradomics research can greatly contribute to our understanding of how microbial pathogens cause disease in vivo and lead to the identification of novel substrates in vivo, and the development of improved therapeutics to counter these pathogens.
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Affiliation(s)
- Natalie C Marshall
- From the ‡Department of Microbiology & Immunology.,§Michael Smith Laboratories
| | - B Brett Finlay
- From the ‡Department of Microbiology & Immunology.,§Michael Smith Laboratories.,¶Department of Biochemistry & Molecular Biology
| | - Christopher M Overall
- ¶Department of Biochemistry & Molecular Biology, .,**Department of Oral Biological & Medical Sciences, Centre for Blood Research, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada
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12
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Otto A, Maaß S, Lassek C, Becher D, Hecker M, Riedel K, Sievers S. The protein inventory of Clostridium difficile grown in complex and minimal medium. Proteomics Clin Appl 2016; 10:1068-1072. [PMID: 27511832 DOI: 10.1002/prca.201600069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 07/21/2016] [Accepted: 08/08/2016] [Indexed: 01/29/2023]
Abstract
The intestinal pathogen Clostridium difficile is causing an increasing number of infections often characterized by severity and high relapse rates. Profound knowledge of the physiology of the pathogen could help to develop new treatment strategies. Proteomics, a valuable tool to study bacterial physiology, was used in this work to establish a benchmark proteome of reference strain C. difficile 630Δerm with MS-based details on all identified proteins. Our elaborate annotation and visualization of C. difficile 630Δerm 3764 ORFs will serve as a valuable base for researchers having to evaluate global expression studies. To exemplify expression variability, protein expression of late exponentially growing cells in complex brain-heart infusion medium and C. difficile minimal medium was compared. Noteworthy results of this comparison are as follows: (i) the higher expression of enzymes for the biosynthesis of some vitamins and purine and (ii) downregulation of proteins involved in butanoate fermentation in C. difficile minimal medium. However, the abundance of proteins involved in DNA metabolism, protein synthesis, and the cell envelope showed no variation between the two growth media.
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Affiliation(s)
- Andreas Otto
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Sandra Maaß
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Christian Lassek
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Dörte Becher
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Michael Hecker
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Katharina Riedel
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Susanne Sievers
- Institute of Microbiology, University of Greifswald, Greifswald, Germany.
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13
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Secretome, surfome and immunome: emerging approaches for the discovery of new vaccine candidates against bacterial infections. World J Microbiol Biotechnol 2016; 32:155. [DOI: 10.1007/s11274-016-2107-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 06/29/2016] [Indexed: 10/21/2022]
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Martinović T, Andjelković U, Gajdošik MŠ, Rešetar D, Josić D. Foodborne pathogens and their toxins. J Proteomics 2016; 147:226-235. [PMID: 27109345 DOI: 10.1016/j.jprot.2016.04.029] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/22/2016] [Accepted: 04/18/2016] [Indexed: 12/18/2022]
Abstract
UNLABELLED Foodborne pathogens, mostly bacteria and fungi, but also some viruses, prions and protozoa, contaminate food during production and processing, but also during storage and transport before consuming. During their growth these microorganisms can secrete different components, including toxins, into the extracellular environment. Other harmful substances can be also liberated and can contaminate food after disintegration of food pathogens. Some bacterial and fungal toxins can be resistant to inactivation, and can survive harsh treatment during food processing. Many of these molecules are involved in cellular processes and can indicate different mechanisms of pathogenesis of foodborne organisms. More knowledge about food contaminants can also help understand their inactivation. In the present review the use of proteomics, peptidomics and metabolomics, in addition to other foodomic methods for the detection of foodborne pathogenic fungi and bacteria, is overviewed. Furthermore, it is discussed how these techniques can be used for discovering biomarkers for pathogenicity of foodborne pathogens, determining the mechanisms by which they act, and studying their resistance upon inactivation in food of animal and plant origin. BIOLOGICAL SIGNIFICANCE Comprehensive and comparative view into the genome and proteome of foodborne pathogens of bacterial or fungal origin and foodomic, mostly proteomic, peptidomic and metabolomic investigation of their toxin production and their mechanism of action is necessary in order to get further information about their virulence, pathogenicity and survival under stress conditions. Furthermore, these data pave the way for identification of biomarkers to trace sources of contamination with food-borne microorganisms and their endo- and exotoxins in order to ensure food safety and prevent the outbreak of food-borne diseases. Therefore, detection of pathogens and their toxins during production, transport and before consume of food produce, as well as protection against food spoilage is a task of great social, economic and public health importance.
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Affiliation(s)
- Tamara Martinović
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia
| | - Uroš Andjelković
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia
| | - Martina Šrajer Gajdošik
- Department of Chemistry, University of J. J. Strossmayer, Cara Hadrijana 8/A, 31000 Osijek, Croatia
| | - Dina Rešetar
- Centre of High-throughput Technologies, Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia
| | - Djuro Josić
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia; Warren Alpert Medical School, Brown University, Providence, RI, USA
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15
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Monitoring in real time the cytotoxic effect of Clostridium difficile upon the intestinal epithelial cell line HT29. J Microbiol Methods 2015; 119:66-73. [PMID: 26436983 DOI: 10.1016/j.mimet.2015.09.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 01/05/2023]
Abstract
The incidence and severity of Clostridium difficile infections (CDI) has been increased not only among hospitalized patients, but also in healthy individuals traditionally considered as low risk population. Current treatment of CDI involves the use of antibiotics to eliminate the pathogen, although recurrent relapses have also been reported. For this reason, the search of new antimicrobials is a very active area of research. The strategy to use inhibitors of toxin's activity has however been less explored in spite of being a promising option. In this regard, the lack of fast and reliable in vitro screening methods to search for novel anti-toxin drugs has hampered this approach. The aim of the current study was to develop a method to monitor in real time the cytotoxicity of C. difficile upon the human colonocyte-like HT29 line, since epithelial intestinal cells are the primary targets of the toxins. The label-free, impedance based RCTA (real time cell analyser) technology was used to follow overtime the behaviour of HT29 in response to C. difficile LMG21717 producing both A and B toxins. Results obtained showed that the selection of the medium to grow the pathogen had a great influence in obtaining toxigenic supernatants, given that some culture media avoided the release of the toxins. A cytotoxic dose- and time-dependent effect of the supernatant obtained from GAM medium upon HT29 and Caco2 cells was detected. The sigmoid-curve fit of data obtained with HT29 allowed the calculation of different toxicological parameters, such as EC50 and LOAEL values. Finally, the modification in the behaviour of HT29 reordered in the RTCA was correlated with the cell rounding effect, typically induced by these toxins, visualized by time-lapsed captures using an optical microscope. Therefore, this RTCA method developed to test cytotoxicity kinetics of C. difficile supernatants upon IEC could be a valuable in vitro model for the screening of new anti-CDI agents.
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16
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Jarocki VM, Tacchi JL, Djordjevic SP. Non-proteolytic functions of microbial proteases increase pathological complexity. Proteomics 2015; 15:1075-88. [PMID: 25492846 PMCID: PMC7167786 DOI: 10.1002/pmic.201400386] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 10/26/2014] [Accepted: 12/05/2014] [Indexed: 12/26/2022]
Abstract
Proteases are enzymes that catalyse hydrolysis of peptide bonds thereby controlling the shape, size, function, composition, turnover and degradation of other proteins. In microbes, proteases are often identified as important virulence factors and as such have been targets for novel drug design. It is emerging that some proteases possess additional non‐proteolytic functions that play important roles in host epithelia adhesion, tissue invasion and in modulating immune responses. These additional “moonlighting” functions have the potential to obfuscate data interpretation and have implications for therapeutic design. Moonlighting enzymes comprise a subcategory of multifunctional proteins that possess at least two distinct biological functions on a single polypeptide chain. Presently, identifying moonlighting proteins relies heavily on serendipitous empirical data with clues arising from proteins lacking signal peptides that are localised to the cell surface. Here, we describe examples of microbial proteases with additional non‐proteolytic functions, including streptococcal pyrogenic exotoxin B, PepO and C5a peptidases, mycoplasmal aminopeptidases, mycobacterial chaperones and viral papain‐like proteases. We explore how these non‐proteolytic functions contribute to host cell adhesion, modulate the coagulation pathway, assist in non‐covalent folding of proteins, participate in cell signalling, and increase substrate repertoire. We conclude by describing how proteomics has aided in moonlighting protein discovery, focusing attention on potential moonlighters in microbial exoproteomes.
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Affiliation(s)
- Veronica M. Jarocki
- The ithree instituteProteomics Core Facility, University of TechnologySydneyNSWAustralia
| | - Jessica L. Tacchi
- The ithree instituteProteomics Core Facility, University of TechnologySydneyNSWAustralia
| | - Steven P. Djordjevic
- The ithree instituteProteomics Core Facility, University of TechnologySydneyNSWAustralia
- Proteomics Core FacilityUniversity of TechnologySydneyNSWAustralia
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17
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Barketi-Klai A, Monot M, Hoys S, Lambert-Bordes S, Kuehne SA, Minton N, Collignon A, Dupuy B, Kansau I. The flagellin FliC of Clostridium difficile is responsible for pleiotropic gene regulation during in vivo infection. PLoS One 2014; 9:e96876. [PMID: 24841151 PMCID: PMC4026244 DOI: 10.1371/journal.pone.0096876] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/12/2014] [Indexed: 01/09/2023] Open
Abstract
Clostridium difficile is the main agent responsible for hospital acquired antibiotic associated diarrhoea. In recent years, epidemic strains have emerged causing more severe infections. Whilst C. difficile has two major virulence factors, toxins TcdA and TcdB, it is generally accepted that other virulence components of the bacterium contribute to disease. Previously, it has been suggested that flagella expression from pathogenic bacteria might be implicated in virulence. In a recent study, we observed an increased mortality in a gnotobiotic mouse model when animals were colonized with an isogenic fliC mutant constructed in the PCR-ribotype 027 (B1/NAP1) strain R20291, while animals survived when colonized by the parental strain or after colonization by other high-toxin-producing C. difficile strains. To understand the reasons for this increased virulence, we compared the global gene expression profiles between the fliC-R20291 mutant and its parental strain using an in vitro and in vivo transcriptomic approach. The latter made use of the gnotobiotic mouse model. Interestingly, in the fliC mutant, we observed considerable up-regulation of genes involved in mobility, membrane transport systems (PTS, ABC transporters), carbon metabolism, known virulence factors and sporulation. A smaller but significant up-regulation of genes involved in cell growth, fermentation, metabolism, stress and antibiotic resistance was also apparent. All of these genes may be associated with the increased virulence of the fliC-R20921 mutant. We confirmed that the fliC mutation is solely responsible for the observed changes in gene expression in the mutant strain since expression profiles were restored to that of the wild-type strain in the fliC-complemented strain. Thus, the absence of FliC is directly or indirectly involved in the high mortality observed in the fliC mutant infected animals. Therefore, we provide the first evidence that when the major structural component of the flagellum is neutralized, deregulation of gene expression can occur during infection.
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Affiliation(s)
- Amira Barketi-Klai
- Faculté de Pharmacie, EA4043, Université Paris Sud, Châtenay-Malabry, France
| | - Marc Monot
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, Paris, France
| | - Sandra Hoys
- Faculté de Pharmacie, EA4043, Université Paris Sud, Châtenay-Malabry, France
| | | | - Sarah A. Kuehne
- Clostridia Research Group, Centre for Biomolecular Sciences, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Nigel Minton
- Clostridia Research Group, Centre for Biomolecular Sciences, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Anne Collignon
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, Paris, France
| | - Bruno Dupuy
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, Paris, France
| | - Imad Kansau
- Faculté de Pharmacie, EA4043, Université Paris Sud, Châtenay-Malabry, France
- * E-mail:
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18
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Chilton CH, Gharbia SE, Fang M, Misra R, Poxton IR, Borriello SP, Shah HN. Comparative proteomic analysis of Clostridium difficile isolates of varying virulence. J Med Microbiol 2014; 63:489-503. [DOI: 10.1099/jmm.0.070409-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The soluble proteome of three Clostridium difficile strains of varying pathogenic potential, designated B-1, Tra 5/5 and 027 SM, were compared using differential in-gel electrophoresis in which the proteins of each strain were labelled with CyDyes. This enabled visual inspection of the 2D profiles of strains and identification of differentially expressed proteins using image analysis software. Unlabelled protein reference maps of the predominant proteins were then generated for each strain using 2D gel electrophoresis followed by protein sequencing of each spot using a Reflectron matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer. Increased coverage of the proteome was achieved using 1D gel electrophoresis in a bottom-up approach using LC-MS/MS of 1 cm gel slices. A total of 888 different proteins were detected by comparative analysis of isolates grown in parallel for 64 h on blood agar plates. Of these, only 38 % were shared between all isolates. One hundred and ten proteins were identified as showing ≥2-fold difference in expression between strains. Differential expression was shown in a number of potential virulence and colonization factors. Toxin B was detected in the more virulent strains B-1 and 027 SM, but not in the lower virulent strain Tra 5/5, despite all strains possessing an intact pathogenicity locus. The S-layer protein (Cwp2) was identified in strains 027 SM and Tra 5/5 but not strain B-1, and differences in the post-translational modification of SlpA were noted for strain B-1. The variant S-layer profile of strain B-1 was confirmed by genomic comparison, which showed a 58 kb insertion in the S-layer operon of strain B-1. Differential post-translation modification events were also noted in flagellar proteins, thought to be due to differential glycosylation. This study highlights genomic and proteomic variation of different Clostridium difficile strains and suggests a number of factors may play a role in mediating the varying virulence of these different strains.
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Affiliation(s)
- C. H. Chilton
- Leeds Institute for Biomedical and Clinical Sciences, University of Leeds, Leeds LS1 3EX, UK
| | - S. E. Gharbia
- Public Health England, Centre for Infections, London NW9 5EQ, UK
| | - M. Fang
- Public Health England, Centre for Infections, London NW9 5EQ, UK
| | - R. Misra
- Public Health England, Centre for Infections, London NW9 5EQ, UK
| | - I. R. Poxton
- College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - S. P. Borriello
- Veterinary Medicines Directorate, Addlestone, Surrey KT15 3NB, UK
| | - H. N. Shah
- Public Health England, Centre for Infections, London NW9 5EQ, UK
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19
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Hensbergen PJ, Klychnikov OI, Bakker D, van Winden VJC, Ras N, Kemp AC, Cordfunke RA, Dragan I, Deelder AM, Kuijper EJ, Corver J, Drijfhout JW, van Leeuwen HC. A novel secreted metalloprotease (CD2830) from Clostridium difficile cleaves specific proline sequences in LPXTG cell surface proteins. Mol Cell Proteomics 2014; 13:1231-44. [PMID: 24623589 DOI: 10.1074/mcp.m113.034728] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Bacterial secreted proteins constitute a biologically important subset of proteins involved in key processes related to infection such as adhesion, colonization, and dissemination. Bacterial extracellular proteases, in particular, have attracted considerable attention, as they have been shown to be indispensable for bacterial virulence. Here, we analyzed the extracellular subproteome of Clostridium difficile and identified a hypothetical protein, CD2830, as a novel secreted metalloprotease. Following the identification of a CD2830 cleavage site in human HSP90β, a series of synthetic peptide substrates was used to identify the favorable CD2830 cleavage motif. This motif was characterized by a high prevalence of proline residues. Intriguingly, CD2830 has a preference for cleaving Pro-Pro bonds, unique among all hitherto described proteases. Strikingly, within the C. difficile proteome two putative adhesion molecules, CD2831 and CD3246, were identified that contain multiple CD2830 cleavage sites (13 in total). We subsequently found that CD2830 efficiently cleaves CD2831 between two prolines at all predicted cleavage sites. Moreover, native CD2830, secreted by live cells, cleaves endogenous CD2831 and CD3246. These findings highlight CD2830 as a highly specific endoproteinase with a preference for proline residues surrounding the scissile bond. Moreover, the efficient cleavage of two putative surface adhesion proteins points to a possible role of CD2830 in the regulation of C. difficile adhesion.
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Affiliation(s)
- Paul J Hensbergen
- Center for Proteomics and Metabolomics, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands
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20
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Ternan NG, Jain S, Graham RLJ, McMullan G. Semiquantitative analysis of clinical heat stress in Clostridium difficile strain 630 using a GeLC/MS workflow with emPAI quantitation. PLoS One 2014; 9:e88960. [PMID: 24586458 PMCID: PMC3933415 DOI: 10.1371/journal.pone.0088960] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 01/16/2014] [Indexed: 12/11/2022] Open
Abstract
Clostridium difficile is considered to be the most frequent cause of infectious bacterial diarrhoea in hospitals worldwide yet its adaptive ability remains relatively uncharacterised. Here, we used GeLC/MS and the exponentially modified protein abundance index (emPAI) calculation to determine proteomic changes in response to a clinically relevant heat stress. Reproducibility between both biological and technical replicates was good, and a 37°C proteome of 224 proteins was complemented by a 41°C proteome of 202 proteins at a 1% false discovery rate. Overall, 236 C. difficile proteins were identified and functionally categorised, of which 178 were available for comparative purposes. A total of 65 proteins (37%) were modulated by 1.5-fold or more at 41°C compared to 37°C and we noted changes in the majority of proteins associated with amino acid metabolism, including upregulation of the reductive branch of the leucine fermentation pathway. Motility was reduced at 41°C as evidenced by a 2.7 fold decrease in the flagellar filament protein, FliC, and a global increase in proteins associated with detoxification and adaptation to atypical conditions was observed, concomitant with decreases in proteins mediating transcriptional elongation and the initiation of protein synthesis. Trigger factor was down regulated by almost 5-fold. We propose that under heat stress, titration of the GroESL and dnaJK/grpE chaperones by misfolded proteins will, in the absence of trigger factor, prevent nascent chains from emerging efficiently from the ribosome causing translational stalling and also an increase in secretion. The current work has thus allowed development of a heat stress model for the key cellular processes of protein folding and export.
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Affiliation(s)
- Nigel G. Ternan
- Northern Ireland Centre for Food and Health (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
- * E-mail:
| | - Shailesh Jain
- Northern Ireland Centre for Food and Health (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
| | - Robert L. J. Graham
- School of Medicine, University of Manchester, Manchester, Greater Manchester, United Kingdom
| | - Geoff McMullan
- Northern Ireland Centre for Food and Health (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
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Identification of a novel zinc metalloprotease through a global analysis of Clostridium difficile extracellular proteins. PLoS One 2013; 8:e81306. [PMID: 24303041 PMCID: PMC3841139 DOI: 10.1371/journal.pone.0081306] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 10/11/2013] [Indexed: 01/05/2023] Open
Abstract
Clostridium difficile is a major cause of infectious diarrhea worldwide. Although the cell surface proteins are recognized to be important in clostridial pathogenesis, biological functions of only a few are known. Also, apart from the toxins, proteins exported by C. difficile into the extracellular milieu have been poorly studied. In order to identify novel extracellular factors of C. difficile, we analyzed bacterial culture supernatants prepared from clinical isolates, 630 and R20291, using liquid chromatography-tandem mass spectrometry. The majority of the proteins identified were non-canonical extracellular proteins. These could be largely classified into proteins associated to the cell wall (including CWPs and extracellular hydrolases), transporters and flagellar proteins. Seven unknown hypothetical proteins were also identified. One of these proteins, CD630_28300, shared sequence similarity with the anthrax lethal factor, a known zinc metallopeptidase. We demonstrated that CD630_28300 (named Zmp1) binds zinc and is able to cleave fibronectin and fibrinogen in vitro in a zinc-dependent manner. Using site-directed mutagenesis, we identified residues important in zinc binding and enzymatic activity. Furthermore, we demonstrated that Zmp1 destabilizes the fibronectin network produced by human fibroblasts. Thus, by analyzing the exoproteome of C. difficile, we identified a novel extracellular metalloprotease that may be important in key steps of clostridial pathogenesis.
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Proteomic Analysis and Label-Free Quantification of the Large Clostridium difficile Toxins. INTERNATIONAL JOURNAL OF PROTEOMICS 2013; 2013:293782. [PMID: 24066231 PMCID: PMC3771451 DOI: 10.1155/2013/293782] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 06/23/2013] [Accepted: 06/24/2013] [Indexed: 01/05/2023]
Abstract
Clostridium difficile is the leading cause of antibiotic-associated diarrhea in hospitals worldwide, due to hypervirulent epidemic strains with the ability to produce increased quantities of the large toxins TcdA and TcdB. Unfortunately, accurate quantification of TcdA and TcdB from different toxinotypes using small samples has not yet been reported. In the present study, we quantify C. difficile toxins in <0.1 mL of culture filtrate by quantitative label-free mass spectrometry (MS) using data-independent analysis (MSE). In addition, analyses of both purified TcdA and TcdB as well as a standard culture filtrate were performed using gel-based and gel-independent proteomic platforms. Gel-based proteomic analysis was then used to generate basic information on toxin integrity and provided sequence confirmation. Gel-independent in-solution digestion of both toxins using five different proteolytic enzymes with MS analysis generated broad amino acid sequence coverage (91% for TcdA and 95% for TcdB). Proteomic analysis of a culture filtrate identified a total of 101 proteins, among them TcdA, TcdB, and S-layer proteins.
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