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Ronish LA, Biswas B, Bauer RM, Jacob ME, Piepenbrink KH. The role of extracellular structures in Clostridioides difficile biofilm formation. Anaerobe 2024; 88:102873. [PMID: 38844261 DOI: 10.1016/j.anaerobe.2024.102873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 04/27/2024] [Accepted: 06/03/2024] [Indexed: 07/08/2024]
Abstract
C. difficile infection (CDI) is a costly and increasing burden on the healthcare systems of many developed countries due to the high rates of nosocomial infections. Despite the availability of several antibiotics with high response rates, effective treatment is hampered by recurrent infections. One potential mechanism for recurrence is the existence of C. difficile biofilms in the gut which persist through the course of antibiotics. In this review, we describe current developments in understanding the molecular mechanisms by which C. difficile biofilms form and are stabilized through extracellular biomolecular interactions.
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Affiliation(s)
- Leslie A Ronish
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Baishakhi Biswas
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Robert M Bauer
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Mallory E Jacob
- Biochemistry Department, University of Geneva, Geneva, Switzerland
| | - Kurt H Piepenbrink
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA; Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
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2
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Buddle JE, Fagan RP. Pathogenicity and virulence of Clostridioides difficile. Virulence 2023; 14:2150452. [PMID: 36419222 DOI: 10.1080/21505594.2022.2150452] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/02/2022] [Accepted: 11/17/2022] [Indexed: 11/25/2022] Open
Abstract
Clostridioides difficile is the most common cause of nosocomial antibiotic-associated diarrhea, and is responsible for a spectrum of diseases characterized by high levels of recurrence, morbidity, and mortality. Treatment is complex, since antibiotics constitute both the main treatment and the major risk factor for infection. Worryingly, resistance to multiple antibiotics is becoming increasingly widespread, leading to the classification of this pathogen as an urgent threat to global health. As a consummate opportunist, C. difficile is well equipped for promoting disease, owing to its arsenal of virulence factors: transmission of this anaerobe is highly efficient due to the formation of robust endospores, and an array of adhesins promote gut colonization. C. difficile produces multiple toxins acting upon gut epithelia, resulting in manifestations typical of diarrheal disease, and severe inflammation in a subset of patients. This review focuses on such virulence factors, as well as the importance of antimicrobial resistance and genome plasticity in enabling pathogenesis and persistence of this important pathogen.
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Affiliation(s)
- Jessica E Buddle
- Molecular Microbiology, School of Biosciences, University of Sheffield, Sheffield, UK
| | - Robert P Fagan
- Molecular Microbiology, School of Biosciences, University of Sheffield, Sheffield, UK
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3
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Bharathkar SK, Miller MJ, Stadtmueller BM. Engineered Secretory Immunoglobulin A provides insights on antibody-based effector mechanisms targeting Clostridiodes difficile. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.08.566291. [PMID: 37986930 PMCID: PMC10659285 DOI: 10.1101/2023.11.08.566291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Secretory (S) Immunoglobin (Ig) A is the predominant mucosal antibody, which mediates host interactions with commensal and pathogenic microbes, including Clostridioides difficile. SIgA adopts a polymeric IgA structure that is bound by secretory component (SC). Despite significance, how SIgA supports diverse effector mechanisms is poorly characterized and SIgA-based therapies nonexistent. We engineered chimeric (c) SIgAs, in which we replaced SC domain D2 with a single domain antibody or a monomeric fluorescent protein, allowing us to investigate and enhance SIgA effector mechanisms. cSIgAs exhibited increased neutralization potency against C. difficile toxins, promoted bacterial clumping and cell rupture, and decreased cytotoxicity. cSIgA also allowed us to visualize and/or quantify C. difficile morphological changes and clumping events. Results reveal mechanisms by which SIgA combats C. difficile infection, demonstrate that cSIgA design can modulate these mechanisms, and demonstrate cSIgA's adaptability to modifications that might target a broad range of antigens and effector mechanisms.
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Affiliation(s)
- Sonya Kumar Bharathkar
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
| | - Michael J. Miller
- Carle R. Woese Institute of Genomic Biology
- Department of food science and Human Nutrition, University of Illinois Urbana-Champaign, Illinois 61801 USA
| | - Beth M. Stadtmueller
- Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
- Department of Biomedical and Translational Sciences, Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois 61801 USA
- Carle R. Woese Institute of Genomic Biology
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4
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Ouyang Z, Zhao H, Zhao M, Yang Y, Zhao J. Type IV pili are involved in phenotypes associated with Clostridioides difficile pathogenesis. Crit Rev Microbiol 2023:1-9. [PMID: 37452617 DOI: 10.1080/1040841x.2023.2235002] [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: 03/13/2023] [Revised: 05/23/2023] [Accepted: 07/05/2023] [Indexed: 07/18/2023]
Abstract
Clostridioides difficile is a Gram-positive, spore-forming, rod-shaped, obligate anaerobe that is the leading cause of antibiotic-associated diarrhea. Type IV pili (T4P) are elongated appendages on the surface of C. difficile that are polymerized from many pilin proteins. T4P play an important role in C. difficile adherence and particularly in its persistence in the host intestine. Recent studies have shown that T4P promote C. difficile aggregation, surface motility, and biofilm formation, which may enhance its pathogenicity. Additionally, the second messenger cyclic diguanylate increases pilA1 transcript abundance, indirectly promoting T4P-mediated aggregation, surface motility, and biofilm formation of C. difficile. This review summarizes recent advances in C. difficile T4P research and the physiological activities of T4P in the context of C. difficile pathogenesis.
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Affiliation(s)
- Zirou Ouyang
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, China
| | - Hanlin Zhao
- Department of Medical Laboratory, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Min Zhao
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, China
| | - Yaxuan Yang
- School of Public Health, The University of Queensland, Brisbane, Queensland, Australia
| | - Jianhong Zhao
- Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, China
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5
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Chandra H, Kovall RA, Yadav JS, Sun X. Host Immune Responses to Surface S-Layer Proteins (SLPs) of Clostridioides difficile. Microorganisms 2023; 11:380. [PMID: 36838345 PMCID: PMC9963625 DOI: 10.3390/microorganisms11020380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/28/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Clostridioides difficile, a nosocomial pathogen, is an emerging gut pathobiont causing antibiotic-associated diarrhea. C. difficile infection involves gut colonization and disruption of the gut epithelial barrier, leading to the induction of inflammatory/immune responses. The expression of two major exotoxins, TcdA and TcdB is the major cause of C. difficile pathogenicity. Attachment of bacterial abundant cell wall proteins or surface S-layer proteins (SLPs) such as SlpA with host epithelial cells is critical for virulence. In addition to being toxins, these surface components have been shown to be highly immunogenic. Recent studies indicate that C. difficile SLPs play important roles in the adhesion of the bacteria to the intestinal epithelial cells, disruption of tight junctions, and modulation of the immune response of the host cells. These proteins might serve as new targets for vaccines and new therapeutic agents. This review summarizes our current understanding of the immunological role of SLPs in inducing host immunity and their use in the development of vaccines and novel therapeutics to combat C. difficile infection.
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Affiliation(s)
- Harish Chandra
- Department of Environmental Microbiology, School of Earth and Environmental Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow 226025, UP, India
- Department of Molecular and Cellular Biosciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Rhett A. Kovall
- Department of Molecular and Cellular Biosciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Jagjit S. Yadav
- Department of Environmental and Public Health Sciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
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6
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Noori M, Azimirad M, Eslami G, Looha MA, Yadegar A, Ghalavand Z, Zali MR. Surface layer protein A from hypervirulent Clostridioides difficile ribotypes induce significant changes in the gene expression of tight junctions and inflammatory response in human intestinal epithelial cells. BMC Microbiol 2022; 22:259. [PMID: 36303110 PMCID: PMC9608920 DOI: 10.1186/s12866-022-02665-0] [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: 03/19/2022] [Revised: 09/22/2022] [Accepted: 10/10/2022] [Indexed: 11/30/2022] Open
Abstract
Background
Surface layer protein A (SlpA), the primary outermost structure of Clostridioides difficile, plays an essential role in C. difficile pathogenesis, although its interaction with host intestinal cells are yet to be understood. The aim of this study was to investigate the effects of SlpA extracted from C. difficile on tight junction (TJ) proteins expression and induction of pro-inflammatory cytokines in human colon carcinoma cell line HT-29. SlpA was extracted from three toxigenic C. difficile clinical strains including RT126, RT001, RT084 as well as C. difficile ATCC 700057 as non-toxigenic strain. Cell viability was performed by MTT assay, and the mRNA expression of TJ proteins and inflammation-associated genes was determined using quantitative RT-PCR. Additionally, the secretion of IL-8, IL-1β and TNF-α cytokines was measured by ELISA. Results C. difficile SlpA from selected RTs variably downregulated the expression level of TJs-assassinated genes and increased the expression level of TLR-4 and pro-inflammatory cytokines in HT-29 treated cells. SlpA from RT126 significantly (padj<0.05) decreased the gene expression level of claudins family and JAM-A and increased the secretion of IL-8, TNF-α and IL1-β as compared to untreated cells. Moreover, only SlpA from RT001 could significantly induce the expression of IL-6 (padj<0.05). Conclusion
The results of the present study highlighted the importance of SlpA in the pathogenesis of CDI and C. difficile-induced inflammatory response in the gut. Further studies are required to unravel the significance of the observed results in promoting the intestinal inflammation and immune response induced by C. difficile SlpA from different RTs. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02665-0.
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Affiliation(s)
- Maryam Noori
- grid.411600.2Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran ,grid.411600.2Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Azimirad
- grid.411600.2Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Gita Eslami
- grid.411600.2Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Azizmohammad Looha
- grid.411600.2Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Yadegar
- grid.411600.2Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zohreh Ghalavand
- grid.411600.2Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zali
- grid.411600.2Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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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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8
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Surface layer protein A from hypervirulent Clostridioides difficile ribotype 001 can induce autophagy process in human intestinal epithelial cells. Microb Pathog 2022; 169:105681. [PMID: 35850375 DOI: 10.1016/j.micpath.2022.105681] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 05/31/2022] [Accepted: 07/12/2022] [Indexed: 11/21/2022]
Abstract
Clostridioides difficile is the leading cause of nosocomial diarrhea with high morbidity and mortality worldwide. C. difficile strains produce a crystalline surface layer protein A (SlpA), which is an absolute necessity for its pathogenesis. However, its pathogenic mechanisms and its pro-inflammatory behavior are not yet fully elucidated. Herein, we report for the first time that SlpA extracted from C. difficile can induce autophagy process in Caco-2 cells. SlpA protein was purified from two C. difficile strains (RT001 and ATCC 700075). The cell viability of Caco-2 cells after exposure with different concentrations (15, 20, 25 μg/mL) of SlpA at various time points (3, 6, 12, 24 h) was measured by MTT assay. Acridine orange staining was used to visualize the hypothetical acidic vesicular organelles. The gene expression of autophagy mediators including LC3B, Atg5, Atg16L, and Beclin-1 was determined by quantitative real-time PCR assay. Western blotting assay was used to detect the expression of LC3B protein. MTT assay showed that different concentrations of SlpA did not induce significant changes in the viability of Caco-2 cells. SlpA at concentration of 20 μg/mL enhanced the formation of acidic vesicular organelles in Caco-2 cells after 12 h of exposure. Moreover, SlpA treatment significantly increased the expression of autophagy-associated genes, and increased the expression of LC3B protein in Caco-2 cells. In conclusion, our study demonstrated that SlpA is capable to induce autophagy in intestinal epithelial cells. These findings reveal a novel mechanism for the pathogenesis of C. difficile mediated by its SLPs.
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9
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Wang S, Zhu D, Sun X. Development of an Effective Nontoxigenic Clostridioides difficile-Based Oral Vaccine against C. difficile Infection. Microbiol Spectr 2022; 10:e0026322. [PMID: 35583336 PMCID: PMC9241731 DOI: 10.1128/spectrum.00263-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022] Open
Abstract
The symptoms of Clostridioides difficile infection (CDI) are largely attributed to two C. difficile toxins, TcdA and TcdB. Significant efforts have been devoted to developing vaccines targeting both toxins through parenteral immunization routes. Recently, we generated a novel chimeric protein (designated Tcd169), comprised of the glucosyltransferase domain (GT), the cysteine protease domain (CPD), and the receptor binding domain (RBD) of TcdB, and the RBD of TcdA. Parenteral immunizations with Tcd169 provide mice effective protection against infection with a ribotype (RT) 027 C. difficile strain. In this study, we expressed Tcd169 in a nontoxigenic C. difficile CCUG37785 strain (designated NTCD), resulting in strain NTCD_Tcd169 to develop an oral vaccine that can target both C. difficile toxins and colonization/adhesion factors. Oral immunizations with NTCD_Tcd169 spores induced systematic and mucosal antibody responses against, not only both toxins, but also C. difficile flagellins (FliC/FliD). Intriguingly yet importantly, anti-Tcd169 sera raised against Tcd169 protein were significantly cross-reactive with FliC/FliD and two surface layer proteins (SlpA and Cwp2). Oral immunizations with NTCD_Tcd169 spores provided mice effective protection against infection with a hypervirulent RT027 C. difficile strain R20291and significantly reduced R20291spore numbers in feces compared with NTCD or PBS immunized mice. These results imply that the genetically modified, nontoxigenic C. difficile strain expressing Tcd169 may represent a novel mucosal vaccine candidate against CDI. IMPORTANCE Clostridioides difficile is an enteric pathogen, and symptoms of C. difficile infection (CDI) are mainly by two exotoxins TcdA and TcdB. Active vaccination is cost-effective approach to prevent CDI and high rates of recurrence. Ideally, vaccines should target both C. difficile toxins and cell/spore colonization. In this study, we expressed immunodominant fragments of TcdA and TcdB (i.e., Tcd169) in a nontoxigenic C. difficile CCUG37785 strain, generating a promising oral/mucosal vaccine candidate against CDI, by targeting both toxins and colonization of pathogenic C. difficile strains. Importantly, anti-Tcd169 sera raised against Tcd169 protein were significantly cross-reactive with FliC/FliD and two surface layer proteins (SlpA and Cwp2), and all of which are involved in C. difficile adhesion/colonization in vitro and in vivo.
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Affiliation(s)
- Shaohui Wang
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Duolong Zhu
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
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10
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Santos MGDC, Trindade CNDR, Vommaro RC, Domingues RMCP, Ferreira EDO. Binding of the extracellular matrix laminin-1 to Clostridioides difficile strains. Mem Inst Oswaldo Cruz 2022; 117:e220035. [PMID: 35730804 PMCID: PMC9208321 DOI: 10.1590/0074-02760220035] [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: 02/08/2022] [Accepted: 04/12/2022] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Clostridioides difficile is the most common cause of nosocomial diarrhea associated with antibiotic use. The disease’s symptoms are caused by enterotoxins, but other surface adhesion factors also play a role in the pathogenesis. These adhesins will bind to components of extracellular matrix. OBJECTIVE There is a lack of knowledge on MSCRAMM, this work set-out to determine the adhesive properties of several C. difficile ribotypes (027, 133, 135, 014, 012) towards laminin-1 (LMN-1). METHODS A binding experiment revealed that different ribotypes have distinct adhesion capabilities. To identify this adhesin, an affinity chromatography column containing LMN-1 was prepared and total protein extracts were analysed using mass spectrometry. FINDINGS Strains from ribotypes 012 and 027 had the best adhesion when incubated with glucose supplementations (0.2%, 0.5%, and 1%), while RT135 had a poor adherence. The criteria were not met by RT014 and RT133. In the absence of glucose, there was no adhesion for any ribotype, implying that glucose is required and plays a significant role in adhesion. MAIN CONCLUSIONS These findings show that in the presence of glucose, each C. difficile ribotype interacts differently with LMN-1, and the adhesin responsible for recognition could be SlpA protein.
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Affiliation(s)
- Mayara Gil de Castro Santos
- Universidade Federal do Rio de Janeiro, Departamento de Microbiologia Médica, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, RJ, Brasil
| | - Camilla Nunes Dos Reis Trindade
- Universidade Federal do Rio de Janeiro, Departamento de Microbiologia Médica, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, RJ, Brasil
| | - Rossiane Cláudia Vommaro
- Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho e Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, Laboratório de Ultraestrutura Celular Hertha Meyer, Rio de Janeiro, RJ, Brasil
| | | | - Eliane de Oliveira Ferreira
- Universidade Federal do Rio de Janeiro, Departamento de Microbiologia Médica, Laboratório de Biologia de Anaeróbios, Rio de Janeiro, RJ, Brasil
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11
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In silico designing of vaccine candidate against Clostridium difficile. Sci Rep 2021; 11:14215. [PMID: 34244557 PMCID: PMC8271013 DOI: 10.1038/s41598-021-93305-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/21/2021] [Indexed: 12/19/2022] Open
Abstract
Clostridium difficile is a spore-forming gram-positive bacterium, recognized as the primary cause of antibiotic-associated nosocomial diarrhoea. Clostridium difficile infection (CDI) has emerged as a major health-associated infection with increased incidence and hospitalization over the years with high mortality rates. Contamination and infection occur after ingestion of vegetative spores, which germinate in the gastro-intestinal tract. The surface layer protein and flagellar proteins are responsible for the bacterial colonization while the spore coat protein, is associated with spore colonization. Both these factors are the main concern of the recurrence of CDI in hospitalized patients. In this study, the CotE, SlpA and FliC proteins are chosen to form a multivalent, multi-epitopic, chimeric vaccine candidate using the immunoinformatics approach. The overall reliability of the candidate vaccine was validated in silico and the molecular dynamics simulation verified the stability of the vaccine designed. Docking studies showed stable vaccine interactions with Toll‐Like Receptors of innate immune cells and MHC receptors. In silico codon optimization of the vaccine and its insertion in the cloning vector indicates a competent expression of the modelled vaccine in E. coli expression system. An in silico immune simulation system evaluated the effectiveness of the candidate vaccine to trigger a protective immune response.
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12
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Chiu PJ, Rathod J, Hong YP, Tsai PJ, Hung YP, Ko WC, Chen JW, Paredes-Sabja D, Huang IH. Clostridioides difficile spores stimulate inflammatory cytokine responses and induce cytotoxicity in macrophages. Anaerobe 2021; 70:102381. [PMID: 34082120 DOI: 10.1016/j.anaerobe.2021.102381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/30/2021] [Accepted: 05/04/2021] [Indexed: 02/08/2023]
Abstract
Clostridioides difficile is a gram-positive, spore-forming anaerobic bacterium, and the leading cause of antibiotic-associated diarrhea worldwide. During C. difficile infection, spores germinate in the presence of bile acids into vegetative cells that subsequently colonize the large intestine and produce toxins. In this study, we demonstrated that C. difficile spores can universally adhere to, and be phagocytosed by, murine macrophages. Only spores from toxigenic strains were able to significantly stimulate the production of inflammatory cytokines by macrophages and subsequently induce significant cytotoxicity. Spores from the isogenic TcdA and TcdB double mutant induced significantly lower inflammatory cytokines and cytotoxicity in macrophages, and these activities were restored by pre-exposure of the spores to either toxins. These findings suggest that during sporulation, spores might be coated with C. difficile toxins from the environment, which could affect C. difficile pathogenesis in vivo.
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Affiliation(s)
- Po-Jung Chiu
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jagat Rathod
- Department of Earth Sciences National Cheng Kung University, Tainan, Taiwan
| | - Yu-Ping Hong
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Pei-Jane Tsai
- Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan, Taiwan; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Yuan-Pin Hung
- Department of Internal Medicine, Tainan Hospital, Ministry of Health and Welfare, Tainan, Taiwan
| | - Wen-Chien Ko
- Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Jenn-Wei Chen
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Daniel Paredes-Sabja
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA; Millennium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - I-Hsiu Huang
- Department of Biochemistry and Microbiology, Oklahoma State University Center for Health Sciences, Tulsa, OK, USA; Oklahoma State University College of Osteopathic Medicine at Cherokee Nation, Tahlequah, OK, USA.
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13
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Polymorphisms in the genes encoding surface associated proteins of Clostridioides difficile isolates. INFECTION GENETICS AND EVOLUTION 2020; 86:104598. [PMID: 33080382 DOI: 10.1016/j.meegid.2020.104598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 10/08/2020] [Accepted: 10/13/2020] [Indexed: 11/21/2022]
Abstract
BACKGROUND Although the diversity of Clostridioides difficile toxins have been extensively studied, little is known about the variation in the surface associated proteins (SAPs) which are important in early steps of bacterial colonization and infection. Here, we examined 65C. difficile isolates to identify polymorphisms in the genes encoding SAPs. METHODS PCR was used to amplify slpA, fliC, fliD, cwp66 and cwp84 genes, followed by sequencing. In addition, the antigenicity and immunogenicity properties of different types of SlpA, FliC, FliD, Cwp66 and Cwp84 proteins were predicted in-silico by VaxiJen and BcePred online servers. RESULTS The predominant slpA sequence type was gr-01 (42.37%), followed by hr-01 (11.86%) and 078-01 (10.16%). In addition, two new slpA subtypes of smz (smz-09-Ir and smz-010-Ir) and a new slpA sequence type (Ir-01) were identified among the isolates examined. Analysis of the nucleotide sequences of fliC, fliD, cwp66 and cwp84 genes revealed 7, 5,5,3 different sequence types, respectively. Insilico analysis of antigenicity of SAPs showed that FliC had the highest level of antigenicity whereas SlpA and Cwp66 proteins had the highest level of immunogenicity. CONCLUSIONS This study pointed to the nucleotide polymorphism in SAPs of C. difficile isolates and demonstrated noticeable diversity in antigenicity and immunogenicity of these proteins which need to be taken into consideration as promising therapeutic or vaccine targets.
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Bassotti G, Marchegiani A, Marconi P, Fettucciari K. The cytotoxic synergy between Clostridioides difficile toxin B and proinflammatory cytokines: an unholy alliance favoring the onset of Clostridioides difficile infection and relapses. Microbiologyopen 2020; 9:e1061. [PMID: 32657021 PMCID: PMC7424247 DOI: 10.1002/mbo3.1061] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/31/2020] [Accepted: 04/30/2020] [Indexed: 02/06/2023] Open
Abstract
Clostridioides difficile infection (CDI) represents an important health problem worldwide, with significant morbidity and mortality. This infection has also high recurrence rates, whose pathophysiological grounds are still poorly understood. Based on our experiments in vitro with Clostridioides difficile toxin B and existing experimental and clinical evidence, we propose that primary CDI and relapses might be favored by a mechanism that involves the enhancement of the toxicity of toxin B by proinflammatory cytokines, tumor necrosis factor alpha, and interferon gamma on the enteric glial cells and their network in an environment characterized by a strong dysmicrobism.
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Affiliation(s)
- Gabrio Bassotti
- Gastroenterology & Hepatology Section, Department of Medicine, University of Perugia Medical School, Perugia, Italy.,Gastroenterology & Hepatology Unit, Santa Maria della Misericordia Hospital, Perugia, Italy
| | - Andrea Marchegiani
- School of Biosciences and Veterinary Medicine, University of Camerino, Macerata, Italy
| | - Pierfrancesco Marconi
- Department of Experimental Medicine, University of Perugia Medical School, Perugia, Italy
| | - Katia Fettucciari
- Department of Experimental Medicine, University of Perugia Medical School, Perugia, Italy
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Rius-Rocabert S, Llinares Pinel F, Pozuelo MJ, García A, Nistal-Villan E. Oncolytic bacteria: past, present and future. FEMS Microbiol Lett 2020; 366:5521890. [PMID: 31226708 DOI: 10.1093/femsle/fnz136] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 06/18/2019] [Indexed: 02/06/2023] Open
Abstract
More than a century ago, independent groups raised the possibility of using bacteria to selectively infect tumours. Such treatment induces an immune reaction that can cause tumour rejection and protect the patient against further recurrences. One of the first holistic approximations to use bacteria in cancer treatment was performed by William Coley, considered the father of immune-therapy, at the end of XIX century. Since then, many groups have used different bacteria to test their antitumour activity in animal models and patients. The basis for this reactivity implies that innate immune responses activated upon bacteria recognition, also react against the tumour. Different publications have addressed several aspects of oncolytic bacteria. In the present review, we will focus on revisiting the historical aspects using bacteria as oncolytic agents and how they led to the current clinical trials. In addition, we address the molecules present in oncolytic bacteria that induce specific toxic effects against the tumors as well as the activation of host immune responses in order to trigger antitumour immunity. Finally, we discuss future perspectives that could be considered in the different fields implicated in the implementation of this kind of therapy in order to improve the current use of bacteria as oncolytic agents.
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Affiliation(s)
- Sergio Rius-Rocabert
- Microbiology Section, Pharmaceutical and Health Science Department. Faculty of Pharmacy. Instituto de Medicina Molecular Aplicada (IMMA). San Pablo-CEU University. CEU Universities, Campus Montepríncipe. Boadilla del Monte, E-28668 Madrid, Spain
| | - Francisco Llinares Pinel
- Microbiology Section, Pharmaceutical and Health Science Department. Faculty of Pharmacy. Instituto de Medicina Molecular Aplicada (IMMA). San Pablo-CEU University. CEU Universities, Campus Montepríncipe. Boadilla del Monte, E-28668 Madrid, Spain
| | - Maria Jose Pozuelo
- Microbiology Section, Pharmaceutical and Health Science Department. Faculty of Pharmacy. Instituto de Medicina Molecular Aplicada (IMMA). San Pablo-CEU University. CEU Universities, Campus Montepríncipe. Boadilla del Monte, E-28668 Madrid, Spain
| | - Antonia García
- Centre for Metabolomics and Bioanalysis (CEMBIO), Chemistry and Biochemistry Department, Faculty of Pharmacy, San Pablo-CEU University, Boadilla del Monte, E-28668 Madrid, Spain
| | - Estanislao Nistal-Villan
- Microbiology Section, Pharmaceutical and Health Science Department. Faculty of Pharmacy. Instituto de Medicina Molecular Aplicada (IMMA). San Pablo-CEU University. CEU Universities, Campus Montepríncipe. Boadilla del Monte, E-28668 Madrid, Spain
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Guerrero-Araya E, Meneses C, Castro-Nallar E, Guzmán D. AM, Álvarez-Lobos M, Quesada-Gómez C, Paredes-Sabja D, Rodríguez C. Origin, genomic diversity and microevolution of the Clostridium difficile B1/NAP1/RT027/ST01 strain in Costa Rica, Chile, Honduras and Mexico. Microb Genom 2020; 6:e000355. [PMID: 32176604 PMCID: PMC7371124 DOI: 10.1099/mgen.0.000355] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 02/28/2020] [Indexed: 12/18/2022] Open
Abstract
Clostridium difficile B1/NAP1/RT027/ST01 has been responsible for outbreaks of antibiotic-associated diarrhoea in clinical settings worldwide and is associated with severe disease presentations and increased mortality rates. Two fluoroquinolone-resistant (FQR) lineages of the epidemic B1/NAP1/RT027/ST01 strain emerged in the USA in the early 1990s and disseminated trans continentally (FQR1 and FQR2). However, it is unclear when and from where they entered Latin America (LA) and whether isolates from LA exhibit unique genomic features when compared to B1/NAP1/RT027/ST01 isolates from other regions of the world. To answer the first issue we compared whole-genome sequences (WGS) of 25 clinical isolates typed as NAP1, RT027 or ST01 in Costa Rica (n=16), Chile (n=5), Honduras (n=3) and Mexico (n=1) to WGS of 129 global isolates from the same genotype using Bayesian phylogenomics. The second question was addressed through a detailed analysis of the number and type of mutations of the LA isolates and their mobile resistome. All but two B1/NAP1/RT027/ST01 isolates from LA belong to the FQR2 lineage (n=23, 92 %), confirming its widespread distribution. As indicated by analysis of a dataset composed of 154 WGS, the B1/NAP1/RT027/ST01 strain was introduced into the four LA countries analysed between 1998 and 2005 from North America (twice) and Europe (at least four times). These events occurred soon after the emergence of the FQR lineages and more than one decade before the first report of the detection of the B1/NAP1/RT027/ST01 in LA. A total of 552 SNPs were identified across all genomes examined (3.8-4.3 Mb) in pairwise comparisons to the R20291 reference genome. Moreover, pairwise SNP distances were among the smallest distances determined in this species so far (0 to 55). Despite this high level of genomic conservation, 39 unique SNPs (7 %) in genes that play roles in the infection process (i.e. slpA) or antibiotic resistance (i.e. rpoB, fusA) distinguished the LA isolates. In addition, isolates from Chile, Honduras and Mexico had twice as many antibiotic resistance genes (ARGs, n=4) than related isolates from other regions. Their unique set of ARGs includes a cfr-like gene and tetM, which were found as part of putative mobile genetic elements whose sequences resemble undescribed integrative and conjugative elements. These results show multiple, independent introductions of B1/NAP1/RT027/ST01 isolates from the FQR1 and FQR2 lineages from different geographical sources into LA and a rather rapid accumulation of distinct mutations and acquired ARG by the LA isolates.
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Affiliation(s)
- Enzo Guerrero-Araya
- Millennium Nucleus in the Biology of Intestinal Microbiota, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
- Microbiota-Host Interactions & Clostridia Research Group, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - Claudio Meneses
- Centro de Biotecnología Vegetal, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
- FONDAP Center for Genome Regulation, Universidad Andrés Bello, Santiago, Chile
| | - Eduardo Castro-Nallar
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - Ana M. Guzmán D.
- Department of Clinical Laboratory, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Manuel Álvarez-Lobos
- Department of Gastroenterology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos Quesada-Gómez
- Facultad de Microbiología & Centro de Investigación en Enfermedades Tropicales (CIET), Universidad de Costa Rica, San José, Costa Rica
| | - Daniel Paredes-Sabja
- Millennium Nucleus in the Biology of Intestinal Microbiota, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
- Microbiota-Host Interactions & Clostridia Research Group, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - César Rodríguez
- Facultad de Microbiología & Centro de Investigación en Enfermedades Tropicales (CIET), Universidad de Costa Rica, San José, Costa Rica
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Chapeton-Montes D, Plourde L, Bouchier C, Ma L, Diancourt L, Criscuolo A, Popoff MR, Brüggemann H. The population structure of Clostridium tetani deduced from its pan-genome. Sci Rep 2019; 9:11220. [PMID: 31375706 PMCID: PMC6677821 DOI: 10.1038/s41598-019-47551-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 07/16/2019] [Indexed: 01/04/2023] Open
Abstract
Clostridium tetani produces a potent neurotoxin, the tetanus neurotoxin (TeNT) that is responsible for the worldwide neurological disease tetanus, but which can be efficiently prevented by vaccination with tetanus toxoid. Until now only one type of TeNT has been characterized and very little information exists about the heterogeneity among C. tetani strains. We report here the genome sequences of 26 C. tetani strains, isolated between 1949 and 2017 and obtained from different locations. Genome analyses revealed that the C. tetani population is distributed in two phylogenetic clades, a major and a minor one, with no evidence for clade separation based on geographical origin or time of isolation. The chromosome of C. tetani is highly conserved; in contrast, the TeNT-encoding plasmid shows substantial heterogeneity. TeNT itself is highly conserved among all strains; the most relevant difference is an insertion of four amino acids in the C-terminal receptor-binding domain in four strains that might impact on receptor-binding properties. Other putative virulence factors, including tetanolysin and collagenase, are encoded in all genomes. This study highlights the population structure of C. tetani and suggests that tetanus-causing strains did not undergo extensive evolutionary diversification, as judged from the high conservation of its main virulence factors.
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Affiliation(s)
| | | | | | - Laurence Ma
- Genomic Platform, Biomics, Institut Pasteur, Paris, France
| | - Laure Diancourt
- CNR Bactéries anaérobies Botulisme, Institut Pasteur, Paris, France
| | - Alexis Criscuolo
- Hub Bioinformatique Biostatistique, Institut Pasteur, Paris, France
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In silico, in vitro and in vivo analysis of putative virulence factors identified in large clostridial toxin-negative, binary toxin- producing C. difficile strains. Anaerobe 2019; 60:102083. [PMID: 31377188 DOI: 10.1016/j.anaerobe.2019.102083] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/28/2019] [Accepted: 07/31/2019] [Indexed: 01/05/2023]
Abstract
The relevance of large clostridial toxin-negative, binary toxin-producing (A-B-CDT+) Clostridium difficile strains in human infection is still controversial. In this study, we investigated putative virulence traits that may contribute to the role of A-B-CDT+C. difficile strains in idiopathic diarrhea. Phenotypic assays were conducted on 148 strains of C. difficile comprising 10 different A-B-CDT+C. difficile ribotypes (RTs): 033, 238, 239, 288, 585, 586, QX143, QX444, QX521 and QX629. A subset of these isolates (n = 53) was whole-genome sequenced to identify genetic loci associated with virulence and survival. Motility studies showed that with the exception of RT 239 all RTs tested were non-motile. C. difficile RTs 033 and 288 had deletions in the F2 and F3 regions of their flagella operon while the F2 region was absent from strains of RTs 238, 585, 586, QX143, QX444, QX521 and QX629. The flagellin and flagella cap genes, fliC and fliD, respectively, involved in adherence and host colonization, were conserved in all strains, including reference strains. All A-B-CDT+C. difficile strains produced at least three extracellular enzymes (deoxyribonuclease, esterase and mucinase) indicating that these are important extracellular proteins. The toxicity of A-B-CDT+C. difficile strains in Vero cells was confirmed, however, pathogenicity was not demonstrated in a mouse model of disease. Despite successful colonization by most strains, there was no evidence of disease in mice. This study provides the first in-depth analysis of A-B-CDT+C. difficile strains and contributes to the current limited knowledge of these strains as a cause of C. difficile infection.
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Yoo IY, Song DJ, Huh HJ, Lee NY. Simultaneous Detection of Clostridioides difficile Glutamate Dehydrogenase and Toxin A/B: Comparison of the C. DIFF QUIK CHEK COMPLETE and RIDASCREEN Assays. Ann Lab Med 2019; 39:214-217. [PMID: 30430786 PMCID: PMC6240517 DOI: 10.3343/alm.2019.39.2.214] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/16/2018] [Accepted: 09/27/2018] [Indexed: 12/15/2022] Open
Abstract
Various commercial assays have recently been developed for detecting glutamate dehydrogenase (GDH) and/or toxin A/B to diagnose Clostridioides difficile infection (CDI). We compared the performance of two assays for the simultaneous detection of C. difficile GDH and toxin A/B, using 150 stool samples: C. DIFF QUIK CHEK COMPLETE (QCC; TechLab, Blacksburg, VA, USA) and RIDASCREEN Clostridium difficile GDH (RC-GDH) and Toxin A/B (RC-Toxin A/B; R-Biopharm, Darmstadt, Germany). For GDH detection, QCC and RC-GDH showed satisfactory sensitivity (95.7% and 94.3%, respectively) and specificity (92.5% and 93.8%, respectively) compared with C. difficile culture. For toxin A/B detection, QCC showed higher sensitivity than RC-Toxin A/B (60.0% vs 33.3%, P<0.001) compared with toxigenic C. difficile culture. When the results of QCC or RC-GDH+RC-Toxin A/B were used as the first step of a two-step algorithm for diagnosing CDI, QCC permitted more accurate discrimination than RC of positive or negative results for CDI (77.3% and 65.3%, respectively). QCC is useful for the simultaneous detection of C. difficile GDH and toxin A/B as a part of the two-step algorithm for diagnosing CDI.
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Affiliation(s)
- In Young Yoo
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Dong Joon Song
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hee Jae Huh
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Nam Yong Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
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