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Malet-Villemagne J, Yucheng L, Evanno L, Denis-Quanquin S, Hugonnet JE, Arthur M, Janoir C, Candela T. Polysaccharide II Surface Anchoring, the Achilles' Heel of Clostridioides difficile. Microbiol Spectr 2023; 11:e0422722. [PMID: 36815772 PMCID: PMC10100865 DOI: 10.1128/spectrum.04227-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/25/2023] [Indexed: 02/24/2023] Open
Abstract
Cell wall glycopolymers (CWPGs) in Gram-positive bacteria have been reported to be involved in several bacterial processes. These polymers, pillars for proteins and S-layer, are essential for the bacterial surface setup, could be essential for growth, and, in pathogens, participate most often in virulence. CWGPs are covalently anchored to peptidoglycan by proteins that belong to the LytR-CpsA-PSr (LCP) family. This anchoring, important for growth, was reported as essential for some bacteria such as Bacillus subtilis, but the reason why CWGP anchoring is essential remains unknown. We studied LcpA and LcpB of Clostridioides difficile and showed that they have a redundant activity. To delete both lcp genes, we set up the first conditional-lethal mutant method in C. difficile and showed that polysaccharide II (PSII) anchoring at the bacterial surface is essential for C. difficile survival. In the conditional-lethal mutant, C. difficile morphology was impaired, suggesting that peptidoglycan synthesis was affected. Because Lcp proteins are transferring CWPGs from the C55-undecaprenyl phosphate (also needed in the peptidoglycan synthesis process), we assumed that there was competition between PSII and peptidoglycan synthesis pathways. We confirmed that UDP-MurNAc-pentapeptide precursor was accumulated, showing that peptidoglycan synthesis was blocked. Our results provide an explanation for the essentiality of PSII anchoring in C. difficile and suggest that the essentiality of the anchoring of CWPGs in other bacteria can also be explained by the blocking of peptidoglycan synthesis. To conclude, our results suggest that Lcps are potential new targets to combat C. difficile infection. IMPORTANCE Cell wall glycopolymers (CWGPs) in Gram-positive bacteria have been reported to be involved in several bacterial processes. CWGP anchoring to peptidoglycan is important for growth and virulence. We set up the first conditional-lethal mutant method in Clostridioides difficile to study LcpA and LcpB involved in the anchoring of CWPGs to peptidoglycan. This study offers new tools to reveal the role of essential genes in C. difficile. LcpA and LcpB activity was shown to be essential, suggesting that they are potential new targets to combat C. difficile infection. In this study, we also showed that there is competition between the polysaccharide II synthesis pathway and peptidoglycan synthesis that probably exists in other Gram-positive bacteria. A better understanding of these mechanisms allows us to define the Lcp proteins as a therapeutic target for potential design of novel antibiotics against pathogenic Gram-positive bacteria.
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Affiliation(s)
| | - Liang Yucheng
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Laurent Evanno
- Biomolécules: Conception, Isolement et Synthèse (BioCIS), Université Paris-Saclay, CNRS, Orsay, France
| | | | - Jean-Emmanuel Hugonnet
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Michel Arthur
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Claire Janoir
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
| | - Thomas Candela
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
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Lacotte PA, Simons A, Bouttier S, Malet-Villemagne J, Nicolas V, Janoir C. Inhibition of In Vitro Clostridioides difficile Biofilm Formation by the Probiotic Yeast Saccharomyces boulardii CNCM I-745 through Modification of the Extracellular Matrix Composition. Microorganisms 2022; 10:microorganisms10061082. [PMID: 35744599 PMCID: PMC9227484 DOI: 10.3390/microorganisms10061082] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/21/2022] [Accepted: 05/21/2022] [Indexed: 12/14/2022] Open
Abstract
Clostridioides difficile is responsible for post-antibiotic diarrhea and most of the pseudomembranous colitis cases. Multiple recurrences, one of the major challenges faced in C. difficile infection (CDI) management, can be considered as chronic infections, and the role of biofilm formation in CDI recurrences is now widely considered. Therefore, we explored if the probiotic yeast Saccharomyces boulardii CNCM I-745 could impact the in vitro formation of C. difficile biofilm. Biomass staining and viable bacterial cell quantification showed that live S. boulardii exerts an antagonistic effect on the biofilm formation for the three C. difficile strains tested. Confocal laser scanning microscopy observation revealed a weakening and an average thickness reduction of the biofilm structure when C. difficile is co-incubated with S. boulardii, compared to the single-species bacterial biofilm structure. These effects, that were not detected with another genetically close yeast, S. cerevisiae, seemed to require direct contact between the probiotic yeast and the bacterium. Quantification of the extrapolymeric matrix components, as well as results obtained after DNase treatment, revealed a significant decrease of eDNA, an essential structural component of the C. difficile biofilm matrix, in the dual-species biofilm. This modification could explain the reduced cohesion and robustness of C. difficile biofilms formed in the presence of S. boulardii CNCM I-745 and be involved in S. boulardii clinical preventive effect against CDI recurrences.
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Affiliation(s)
- Pierre-Alexandre Lacotte
- INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, 92290 Châtenay-Malabry, France; (P.-A.L.); (A.S.); (S.B.); (J.M.-V.)
| | - Alexis Simons
- INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, 92290 Châtenay-Malabry, France; (P.-A.L.); (A.S.); (S.B.); (J.M.-V.)
- Laboratoire Eau, Environnement et Systèmes Urbains (Leesu), Université Paris-Est Créteil, École des Ponts ParisTech, 94010 Créteil, France
| | - Sylvie Bouttier
- INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, 92290 Châtenay-Malabry, France; (P.-A.L.); (A.S.); (S.B.); (J.M.-V.)
| | - Jeanne Malet-Villemagne
- INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, 92290 Châtenay-Malabry, France; (P.-A.L.); (A.S.); (S.B.); (J.M.-V.)
| | - Valérie Nicolas
- Ingénierie et Plateformes au Service de l’Innovation (IPSIT), UMS IPSIT Université Paris-Saclay-US 31 INSERM-UAR 3679 CNRS, Plateforme d’Imagerie Cellulaire MIPSIT, 92290 Châtenay-Malabry, France;
| | - Claire Janoir
- INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, 92290 Châtenay-Malabry, France; (P.-A.L.); (A.S.); (S.B.); (J.M.-V.)
- Correspondence:
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Doan THD, Bernet-Camard MF, Hoÿs S, Janoir C, Péchiné S. Impact of Subinhibitory Concentrations of Metronidazole on Morphology, Motility, Biofilm Formation and Colonization of Clostridioides difficile. Antibiotics (Basel) 2022; 11:624. [PMID: 35625268 PMCID: PMC9137534 DOI: 10.3390/antibiotics11050624] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/22/2022] [Accepted: 04/27/2022] [Indexed: 12/04/2022] Open
Abstract
Clostridioides difficile infection (CDI) is the primary cause of health-care-associated infectious diarrhea. Treatment requires mostly specific antibiotics such as metronidazole (MTZ), vancomycin or fidaxomicin. However, approximately 20% of treated patients experience recurrences. Treatment with MTZ is complicated by reduced susceptibility to this molecule, which could result in high failure and recurrence rates. However, the mechanism remains unclear. In this study, we investigated the impact of subinhibitory concentrations of MTZ on morphology, motility, biofilm formation, bacterial adherence to the intestinal Caco-2/TC7 differentiated monolayers, and colonization in monoxenic and conventional mouse models of two C. difficile strains (VPI 10463 and CD17-146), showing different susceptibility profiles to MTZ. Our results revealed that in addition to the inhibition of motility and the downregulation of flagellar genes for both strains, sub-inhibitory concentrations of MTZ induced various in vitro phenotypes for the strain CD17-146 exhibiting a reduced susceptibility to this antibiotic: elongated morphology, enhanced biofilm production and increased adherence to Caco-2/TC7 cells. Weak doses of MTZ induced higher level of colonization in the conventional mouse model and a trend to thicker 3-D structures entrapping bacteria in monoxenic mouse model. Thus, sub-inhibitory concentrations of MTZ can have a wide range of physiological effects on bacteria, which may contribute to their persistence after treatment.
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Affiliation(s)
| | - Marie-Françoise Bernet-Camard
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350 Jouy-en-Josas, France; (M.-F.B.-C.); (S.H.); (C.J.)
| | - Sandra Hoÿs
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350 Jouy-en-Josas, France; (M.-F.B.-C.); (S.H.); (C.J.)
| | - Claire Janoir
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350 Jouy-en-Josas, France; (M.-F.B.-C.); (S.H.); (C.J.)
| | - Séverine Péchiné
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350 Jouy-en-Josas, France; (M.-F.B.-C.); (S.H.); (C.J.)
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Coullon H, Rifflet A, Wheeler R, Janoir C, Boneca IG, Candela T. Peptidoglycan analysis reveals that synergistic deacetylase activity in vegetative Clostridium difficile impacts the host response. J Biol Chem 2020; 295:16785-16796. [PMID: 32978253 PMCID: PMC7864072 DOI: 10.1074/jbc.ra119.012442] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 09/23/2020] [Indexed: 12/21/2022] Open
Abstract
Clostridium difficile is an anaerobic and spore-forming bacterium responsible for 15-25% of postantibiotic diarrhea and 95% of pseudomembranous colitis. Peptidoglycan is a crucial element of the bacterial cell wall that is exposed to the host, making it an important target for the innate immune system. The C. difficile peptidoglycan is largely N-deacetylated on its glucosamine (93% of muropeptides) through the activity of enzymes known as N-deacetylases, and this N-deacetylation modulates host-pathogen interactions, such as resistance to the bacteriolytic activity of lysozyme, virulence, and host innate immune responses. C. difficile genome analysis showed that 12 genes potentially encode N-deacetylases; however, which of these N-deacetylases are involved in peptidoglycan N-deacetylation remains unknown. Here, we report the enzymes responsible for peptidoglycan N-deacetylation and their respective regulation. Through peptidoglycan analysis of several mutants, we found that the N-deacetylases PdaV and PgdA act in synergy. Together they are responsible for the high level of peptidoglycan N-deacetylation in C. difficile and the consequent resistance to lysozyme. We also characterized a third enzyme, PgdB, as a glucosamine N-deacetylase. However, its impact on N-deacetylation and lysozyme resistance is limited, and its physiological role remains to be dissected. Finally, given the influence of peptidoglycan N-deacetylation on host defense against pathogens, we investigated the virulence and colonization ability of the mutants. Unlike what has been shown in other pathogenic bacteria, a lack of N-deacetylation in C. difficile is not linked to a decrease in virulence.
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Affiliation(s)
- Héloise Coullon
- Université Paris-Saclay, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Aline Rifflet
- Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, Paris, France; INSERM, Équipe Avenir, Paris; CNRS, UMR 2001 "Microbiologie Intégrative et Moléculaire," Paris, France
| | - Richard Wheeler
- Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, Paris, France; INSERM, Équipe Avenir, Paris; CNRS, UMR 2001 "Microbiologie Intégrative et Moléculaire," Paris, France
| | - Claire Janoir
- Université Paris-Saclay, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Ivo G Boneca
- Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, Paris, France; INSERM, Équipe Avenir, Paris; CNRS, UMR 2001 "Microbiologie Intégrative et Moléculaire," Paris, France
| | - Thomas Candela
- Université Paris-Saclay, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.
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Couturier J, Franconeri L, Janoir C, Ferraris L, Syed-Zaidi R, Youssouf A, Gateau C, Hoys S, Aires J, Barbut F. Characterization of Non-Toxigenic Clostridioides difficile Strains Isolated from Preterm Neonates and In Vivo Study of Their Protective Effect. J Clin Med 2020; 9:jcm9113650. [PMID: 33202811 PMCID: PMC7696784 DOI: 10.3390/jcm9113650] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 12/24/2022] Open
Abstract
In a previous monocentric study in preterm neonates (PN), we described a high Clostridioides difficile colonization rate (74%) with two uncommon non-toxigenic strains (NTCD) belonging to PCR-ribotype (RT) (CE)847 and (CE)032. To determine the extent of carriage of both NTCD in other spatio-temporal settings, strains isolated in PN stools from two multicenter cohorts were characterized by PCR-ribotyping, MLVA and MLST. We also evaluated the protective role of two NTCD from these RT against C. difficile infection in a hamster caecitis model. Animals were administered either each NTCD alone (n = 7), or followed by a 027 strain (n = 9). A control group received only the 027 strain (n = 8). Clinical activity and colonization by C. difficile in stools were monitored daily until death or sacrifice at D20. We isolated 18 RT(CE)032 (ST-83) strains and 2 RT(CE)847 (ST-26) strains among 247 PN from both cohorts. Within each RT, strains were genetically related. The survival rate was significantly increased when animals received a RT(CE)847 or (CE)032 strain before the 027 strain (4/9 deaths, p = 0.029; 1/9 death, p = 0.0004, respectively). We describe two predominant uncommon NTCD strains, in a PN population from different healthcare facilities. Both NTCD provide a potential protection against C. difficile infection.
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Affiliation(s)
- Jeanne Couturier
- Faculty of Pharmacy, Paris University, INSERM UMR S-1139, 4 Avenue de l’Observatoire, 75006 Paris, France; (L.F.); (J.A.); (F.B.)
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
- Correspondence:
| | - Léa Franconeri
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
| | - Claire Janoir
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 92290 Châtenay-Malabry, France; (C.J.); (S.H.)
| | - Laurent Ferraris
- Faculty of Pharmacy, Paris University, INSERM UMR S-1139, 4 Avenue de l’Observatoire, 75006 Paris, France; (L.F.); (J.A.); (F.B.)
| | - Rabab Syed-Zaidi
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
| | - Anlyata Youssouf
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
| | - Cécile Gateau
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
| | - Sandra Hoys
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 92290 Châtenay-Malabry, France; (C.J.); (S.H.)
| | - Julio Aires
- Faculty of Pharmacy, Paris University, INSERM UMR S-1139, 4 Avenue de l’Observatoire, 75006 Paris, France; (L.F.); (J.A.); (F.B.)
| | - Frédéric Barbut
- Faculty of Pharmacy, Paris University, INSERM UMR S-1139, 4 Avenue de l’Observatoire, 75006 Paris, France; (L.F.); (J.A.); (F.B.)
- National Reference Center for Clostridioides difficile, Saint-Antoine Hospital, 184 rue du Faubourg Saint-Antoine, 75012 Paris, France; (L.F.); (R.S.-Z.); (A.Y.); (C.G.)
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Marvaud JC, Quevedo-Torres S, Eckert C, Janoir C, Barbut F. Virulence of new variant strains of Clostridium difficile producing only toxin A or binary toxin in the hamster model. New Microbes New Infect 2019; 32:100590. [PMID: 31516714 PMCID: PMC6734109 DOI: 10.1016/j.nmni.2019.100590] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 06/26/2019] [Accepted: 08/06/2019] [Indexed: 01/05/2023] Open
Abstract
Pathogenesis of Clostridium difficile has been linked to production of toxins, including the large toxins A and B as well as the binary toxin CDT. Until recently, toxin A was only found in combination in clinical strains with the toxin B, unlike toxin B or CDT, which were found alone in toxigenic variants. New toxigenic variants of C. difficile detected in our laboratory from patients with diarrhoea or severe colitis, including a variant producing only toxin A, were tested for virulence in the hamster model, which displays the clinical features of C. difficile disease. Hamsters infected with a strain producing only toxin B induced similar clinical signs, time to death from infection and histologic damage compared to the hypervirulent strain 027. No mortality or clinical signs of infection but caecal histologic damage was found with the variant producing only toxin A. The C. difficile variant strain producing only CDT was able to kill one hamster out of seven; nevertheless, the surviving animals had few alteration of the caecum.
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Affiliation(s)
- J.-C. Marvaud
- EA 7359 ‘Unité Bactéries Pathogènes et Santé’ (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
- Corresponding author: J.-C. Marvaud, 1EA 4043 ‘Unité Bactéries Pathogènes et Santé’ (UBaPS), Université Paris-Sud, Université 8, Paris-Saclay, 92290, Châtenay-Malabry, France.
| | - S. Quevedo-Torres
- EA 7359 ‘Unité Bactéries Pathogènes et Santé’ (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
- AP-HP, Hôpital Saint Antoine National Reference Laboratory for C. difficile, Paris, France
| | - C. Eckert
- AP-HP, Hôpital Saint Antoine National Reference Laboratory for C. difficile, Paris, France
| | - C. Janoir
- EA 7359 ‘Unité Bactéries Pathogènes et Santé’ (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - F. Barbut
- AP-HP, Hôpital Saint Antoine National Reference Laboratory for C. difficile, Paris, France
- Université Paris Descartes, Faculté de Pharmacie de Paris, UMR-S1139, Sorbonne Paris Cité, Paris, France
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Bradshaw WJ, Bruxelle JF, Kovacs-Simon A, Harmer NJ, Janoir C, Péchiné S, Acharya KR, Michell SL. Molecular features of lipoprotein CD0873: A potential vaccine against the human pathogen Clostridioides difficile. J Biol Chem 2019; 294:15850-15861. [PMID: 31420448 PMCID: PMC6816091 DOI: 10.1074/jbc.ra119.010120] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/15/2019] [Indexed: 01/10/2023] Open
Abstract
Clostridioides difficile is the primary cause of antibiotic-associated diarrhea and colitis, a healthcare-associated intestinal disease resulting in a significant fatality rate. Colonization of the gut is critical for C. difficile pathogenesis. The bacterial molecules essential for efficient colonization therefore offer great potential as vaccine candidates. Here we present findings demonstrating that the C. difficile immunogenic lipoprotein CD0873 plays a critical role in pathogen success in vivo. We found that in a dixenic colonization model, a CD0873-positive strain of C. difficile significantly outcompeted a CD0873-negative strain. Immunization of mice with recombinant CD0873 prevented long-term gut colonization and was correlated with a strong secretory IgA immune response. We further present high-resolution crystal structures of CD0873, at 1.35–2.50 Å resolutions, offering a first view of the ligand-binding pocket of CD0873 and provide evidence that this lipoprotein adhesin is part of a tyrosine import system, an amino acid key in C. difficile infection. These findings suggest that CD0873 could serve as an effective component in a vaccine against C. difficile.
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Affiliation(s)
- William J Bradshaw
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Jean-François Bruxelle
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), University Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Andrea Kovacs-Simon
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Nicholas J Harmer
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom.,Living Systems Institute, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Claire Janoir
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), University Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Severine Péchiné
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), University Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Stephen L Michell
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
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Spitz C, Mathias F, Péchiné S, Doan THD, Innocent J, Pellissier S, Di Giorgio C, Crozet MD, Janoir C, Vanelle P. 2,4-Disubstituted 5-Nitroimidazoles Potent against Clostridium difficile. ChemMedChem 2019; 14:561-569. [PMID: 30644169 DOI: 10.1002/cmdc.201800784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Indexed: 12/17/2022]
Abstract
Metronidazole is one of the first-line treatments for non-severe Clostridium difficile infections (CDI). However, resistance limits its use in cases of severe and complicated CDI. Structure-activity relationships previously described for the 5-nitroimidazole series have shown that functionalization at the 2- and 4-positions can impart better activity against parasites and anaerobic bacteria than metronidazole. Herein we report the synthesis of new 2,4-disubstituted 5-nitroimidazole compounds that show potent antibacterial activity against C. difficile. We used a vicarious nucleophilic substitution of hydrogen (VNS) reaction to introduce a phenylmethylsulfone at the 4-position and a unimolecular radical nucleophilic substitution (SRN 1) reaction to introduce an ethylenic function at the 2-position of the 5-nitroimidazole scaffold.
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Affiliation(s)
- Cédric Spitz
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
| | - Fanny Mathias
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
| | - Séverine Péchiné
- EA4043 Faculté de Pharmacie, Univ Paris-Sud, Université Paris-Saclay, Chatenay-Malabry, France
| | - Tri Hanh Dung Doan
- EA4043 Faculté de Pharmacie, Univ Paris-Sud, Université Paris-Saclay, Chatenay-Malabry, France
| | - Jean Innocent
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
| | - Sylvain Pellissier
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
| | - Carole Di Giorgio
- Laboratoire de Mutagénèse Environnementale, Aix-Marseille Université, CNRS, IRD, Avignon Université, IMBE UMR 7263, 13385, Marseille, France
| | - Maxime D Crozet
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
| | - Claire Janoir
- EA4043 Faculté de Pharmacie, Univ Paris-Sud, Université Paris-Saclay, Chatenay-Malabry, France
| | - Patrice Vanelle
- Aix-Marseille Université, Institut de Chimie Radicalaire ICR, UMR CNRS 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin - CS 30064, 13385, Marseille Cedex 05, France
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9
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Palmieri LJ, Rainteau D, Sokol H, Beaugerie L, Dior M, Coffin B, Humbert L, Eguether T, Bado A, Hoys S, Janoir C, Duboc H. Inhibitory Effect of Ursodeoxycholic Acid on Clostridium difficile Germination Is Insufficient to Prevent Colitis: A Study in Hamsters and Humans. Front Microbiol 2018; 9:2849. [PMID: 30524414 PMCID: PMC6262072 DOI: 10.3389/fmicb.2018.02849] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/06/2018] [Indexed: 12/12/2022] Open
Abstract
Introduction: Bile acids (BA) influence germination and growth of Clostridium difficile. Ursodeoxycholic acid (UDCA), a BA minor in human, used for cholestatic liver diseases, inhibits germination and growth of C. difficile in vitro, but was never tested in vivo with an infectious challenge versus control. We hypothesized that UDCA could prevent CDI. We evaluated the effects of UDCA on C. difficile in vitro and in hamsters, with pharmacokinetics study and with an infectious challenge. Then, we studied CDI incidence in UDCA–treated patients. Methods: We evaluated germination and growth of C. difficile, with 0.01, 0.05, and 0.1% UDCA. We analyzed fecal BA of hamsters receiving antibiotics and UDCA (50 mg/kg/day), antibiotics, or UDCA alone. Then, we challenged with spores of C. difficile at D6 hamsters treated with UDCA (50 mg/kg/day) from D1 to D13, versus control. In human, we analyzed the database of a cohort on CDI in acute flares of inflammatory bowel disease (IBD). As PSC-IBD patients were under UDCA treatment, we compared PSC-IBD patients to IBD patients without PSC. Results:In vitro, UDCA inhibited germination and growth of C. difficile at 0.05 and 0.1%, competing with 0.1% TCA (with 0.1%: 0.05% ± 0.05% colony forming unit versus 100% ± 0%, P < 0.0001). In hamsters, UDCA reached high levels only when administered with antibiotics (43.5% UDCA at D5). Without antibiotics, UDCA was in small amount in feces (max. 4.28%), probably because of UDCA transformation into LCA by gut microbiota. During infectious challenge, mortality was similar in animals treated or not with UDCA (62.5%, n = 5/8, P = 0.78). UDCA percentage was high, similar and with the same kinetics in dead and surviving hamsters. However, dead hamsters had a higher ratio of primary over secondary BA compared to surviving hamsters. 9% (n = 41/404) of IBD patients without PSC had a CDI, versus 25% (n = 4/12) of PSC-IBD patients treated with UDCA. Conclusion: We confirmed the inhibitory effect of UDCA on growth and germination of C. difficile in vitro, with 0.05 or 0.1% UDCA. However, in our hamster model, UDCA was inefficient to prevent CDI, despite high levels of UDCA in feces. Patients with PSC-IBD treated with UDCA did not have less CDI than IBD patients.
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Affiliation(s)
- Lola-Jade Palmieri
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France.,EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.,INSERM U1149, Centre de Recherche sur l'Inflammation, Faculté de Médecine Paris Diderot, Université Paris Diderot, Paris, France
| | - Dominique Rainteau
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France
| | - Harry Sokol
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France.,Department of Gastroenterology and Nutrition, Saint Antoine Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Laurent Beaugerie
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France.,Department of Gastroenterology and Nutrition, Saint Antoine Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Marie Dior
- Department of Gastroenterology, Louis Mourier Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Benoit Coffin
- INSERM U1149, Centre de Recherche sur l'Inflammation, Faculté de Médecine Paris Diderot, Université Paris Diderot, Paris, France.,Department of Gastroenterology, Louis Mourier Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Lydie Humbert
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France
| | - Thibaut Eguether
- ERL INSERM U1157/UMR7203, PM2, Assistance Publique-Hôpitaux de Paris (AP-HP), Faculté de Médecine Saint-Antoine, Sorbonne Université, Paris, France
| | - André Bado
- INSERM U1149, Centre de Recherche sur l'Inflammation, Faculté de Médecine Paris Diderot, Université Paris Diderot, Paris, France
| | - Sandra Hoys
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Claire Janoir
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Henri Duboc
- INSERM U1149, Centre de Recherche sur l'Inflammation, Faculté de Médecine Paris Diderot, Université Paris Diderot, Paris, France.,Department of Gastroenterology, Louis Mourier Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
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10
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Coullon H, Rifflet A, Wheeler R, Janoir C, Boneca IG, Candela T. N-Deacetylases required for muramic-δ-lactam production are involved in Clostridium difficile sporulation, germination, and heat resistance. J Biol Chem 2018; 293:18040-18054. [PMID: 30266804 DOI: 10.1074/jbc.ra118.004273] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/24/2018] [Indexed: 01/08/2023] Open
Abstract
Spores are produced by many organisms as a survival mechanism activated in response to several environmental stresses. Bacterial spores are multilayered structures, one of which is a peptidoglycan layer called the cortex, containing muramic-δ-lactams that are synthesized by at least two bacterial enzymes, the muramoyl-l-alanine amidase CwlD and the N-deacetylase PdaA. This study focused on the spore cortex of Clostridium difficile, a Gram-positive, toxin-producing anaerobic bacterial pathogen that can colonize the human intestinal tract and is a leading cause of antibiotic-associated diarrhea. Using ultra-HPLC coupled with high-resolution MS, here we found that the spore cortex of the C. difficile 630Δerm strain differs from that of Bacillus subtilis Among these differences, the muramic-δ-lactams represented only 24% in C. difficile, compared with 50% in B. subtilis CD630_14300 and CD630_27190 were identified as genes encoding the C. difficile N-deacetylases PdaA1 and PdaA2, required for muramic-δ-lactam synthesis. In a pdaA1 mutant, only 0.4% of all muropeptides carried a muramic-δ-lactam modification, and muramic-δ-lactams were absent in the cortex of a pdaA1-pdaA2 double mutant. Of note, the pdaA1 mutant exhibited decreased sporulation, altered germination, decreased heat resistance, and delayed virulence in a hamster infection model. These results suggest a much greater role for muramic-δ-lactams in C. difficile than in other bacteria, including B. subtilis In summary, the spore cortex of C. difficile contains lower levels of muramic-δ-lactams than that of B. subtilis, and PdaA1 is the major N-deacetylase for muramic-δ-lactam biosynthesis in C. difficile, contributing to sporulation, heat resistance, and virulence.
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Affiliation(s)
- Héloise Coullon
- From the EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry
| | - Aline Rifflet
- the Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, 75724 Paris, and; INSERM, Équipe Avenir, 75015 Paris, France
| | - Richard Wheeler
- the Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, 75724 Paris, and; INSERM, Équipe Avenir, 75015 Paris, France
| | - Claire Janoir
- From the EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry
| | - Ivo Gomperts Boneca
- the Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, 75724 Paris, and; INSERM, Équipe Avenir, 75015 Paris, France
| | - Thomas Candela
- From the EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry,.
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11
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Bruxelle J, Tsapis N, Hoys S, Collignon A, Janoir C, Fattal E, Péchiné S. Protection against Clostridium difficile infection in a hamster model by oral vaccination using flagellin FliC-loaded pectin beads. Vaccine 2018; 36:6017-6021. [DOI: 10.1016/j.vaccine.2018.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/29/2018] [Accepted: 08/05/2018] [Indexed: 01/03/2023]
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12
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Péchiné S, Bruxelle JF, Janoir C, Collignon A. Targeting Clostridium difficile Surface Components to Develop Immunotherapeutic Strategies Against Clostridium difficile Infection. Front Microbiol 2018; 9:1009. [PMID: 29875742 PMCID: PMC5974105 DOI: 10.3389/fmicb.2018.01009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 04/30/2018] [Indexed: 12/18/2022] Open
Abstract
New therapies are needed to prevent and treat Clostridium difficile infection and to limit the rise in antibiotic resistance. Besides toxins, several surface components have been characterized as colonization factors and have been shown as immunogenic. This review will focus on passive and active immunization strategies targeting C. difficile surface components to combat C. difficile. Concerning passive immunization, the first strategies used antisera raised against the entire bacterium to prevent infection in the hamster model. Then, surface components such as the flagellin and the S-layer proteins were used for immunization and the passive transfer of antibodies was protective in animal models. Passive immunotherapy with polyvalent immunoglobulins was used in humans and bovine immunoglobulin concentrates were evaluated in clinical trials. Concerning active immunization, vaccine assays targeting surface components were tested mainly in animal models, mouse models of colonization and hamster models of infection. Bacterial extracts, spore proteins and surface components of vegetative cells such as cell wall proteins, flagellar proteins, and polysaccharides were used as vaccine targets. Vaccine assays were performed by parenteral and mucosal routes of immunization. Both gave promising results and pave the way to development of new vaccines.
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Affiliation(s)
- Séverine Péchiné
- EA 4043, Unités Bactéries Pathogènes et Santé, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Jean F Bruxelle
- EA 4043, Unités Bactéries Pathogènes et Santé, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Claire Janoir
- EA 4043, Unités Bactéries Pathogènes et Santé, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Anne Collignon
- EA 4043, Unités Bactéries Pathogènes et Santé, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
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13
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Pantaléon V, Monot M, Eckert C, Hoys S, Collignon A, Janoir C, Candela T. Clostridium difficile forms variable biofilms on abiotic surface. Anaerobe 2018; 53:34-37. [PMID: 29859742 DOI: 10.1016/j.anaerobe.2018.05.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 05/14/2018] [Accepted: 05/18/2018] [Indexed: 01/06/2023]
Abstract
Clostridium difficile can form biofilms. Thirty-seven strains were characterized for their ability to form a biofilm, adhesion on an inert surface and hydrophobicity. No correlation between the ability to form a biofilm and the strain virulence was highlighted. However, non-motile strains were not able to form a high biofilm.
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Affiliation(s)
- V Pantaléon
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - M Monot
- Département de Microbiologie, Institut Pasteur, Laboratoire Pathogenèse des Bactéries Anaérobies, Paris, France; Département de Microbiologie et d'infectiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC, Canada; Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - C Eckert
- National Reference Laboratory for C. difficile, Assistance Publique-Hôpitaux de Paris, Hôpital Saint-Antoine, Paris, France; Sorbonne Université, Centre d'immunologie et des Maladies Infectieuses-Paris, Cimi-Paris, Département de Bactériologie, AP-HP, Hôpitaux Universitaires de l'Est Parisien, F-75012 Paris, France
| | - S Hoys
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - A Collignon
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - C Janoir
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - T Candela
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290 Châtenay-Malabry, France.
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14
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Bruxelle JF, Mizrahi A, Hoÿs S, Collignon A, Janoir C, Péchiné S. Clostridium difficile flagellin FliC: Evaluation as adjuvant and use in a mucosal vaccine against Clostridium difficile. PLoS One 2017; 12:e0187212. [PMID: 29176760 PMCID: PMC5703446 DOI: 10.1371/journal.pone.0187212] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/16/2017] [Indexed: 12/17/2022] Open
Abstract
The immunogenicity of bacterial flagellin has been reported in different studies. By its close interaction with the immune system, the flagellin represents an interesting adjuvant and vaccine candidate. Salmonella Typhimurium flagellin has already been tested as adjuvant to stimulate mucosal immunity. Here, we assessed the ability of Clostridium difficile flagellin FliC to act as a mucosal adjuvant, first combined with ovalbumin as antigen and second with a C. difficile surface protein, the precursor of the S-layer proteins SlpA. Using ovalbumin as antigen, we compared the gut mucosal adjuvanticity of FliC to Salmonella Typhimurium flagellin and cholera toxin. Two routes of immunization were tested in a mouse model: intra-rectal and intra-peritoneal, following which, gut mucosal and systemic antibody responses against ovalbumin (Immunoglobulins G and Immunoglobulins A) were analyzed by Enzyme-Linked Immuno Assay in intestinal contents and in sera. In addition, ovalbumin-specific immunoglobulin producing cells were detected in the intestinal lamina propria by Enzyme-Linked Immunospot. Results showed that FliC as adjuvant for immunization targeting ovalbumin was able to stimulate a gut mucosal and systemic antibody response independently of the immunization route. In order to develop a mucosal vaccine to prevent C. difficile intestinal colonization, we assessed in a mouse model the efficacy of FliC as adjuvant compared with cholera toxin co-administrated with the C. difficile S-layer precursor SlpA as antigen. After challenge, a significant decrease of C. difficile intestinal colonization was observed in immunized groups compared to the control group. Our results showed that C. difficile FliC could be used as adjuvant in mucosal vaccination strategy against C. difficile infections.
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Affiliation(s)
- Jean-François Bruxelle
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Assaf Mizrahi
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
- Service de Microbiologie Clinique, Groupe Hospitalier Paris Saint Joseph, Paris, France
| | - Sandra Hoÿs
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Anne Collignon
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Claire Janoir
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
| | - Séverine Péchiné
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry Cedex, France
- * E-mail:
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15
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Soavelomandroso AP, Gaudin F, Hoys S, Nicolas V, Vedantam G, Janoir C, Bouttier S. Biofilm Structures in a Mono-Associated Mouse Model of Clostridium difficile Infection. Front Microbiol 2017; 8:2086. [PMID: 29118745 PMCID: PMC5661025 DOI: 10.3389/fmicb.2017.02086] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 10/11/2017] [Indexed: 12/31/2022] Open
Abstract
Clostridium difficile infection (CDI) is a major healthcare-associated disease with high recurrence rates. Host colonization is critical for the infectious process, both in first episodes and in recurrent disease, with biofilm formation playing a key role. The ability of C. difficile to form a biofilm on abiotic surfaces is established, but has not yet been confirmed in the intestinal tract. Here, four different isolates of C. difficile, which are in vitro biofilm producers, were studied for their ability to colonize germ-free mice. The level of colonization achieved was similar for all isolates in the different parts of the murine gastrointestinal tract, but pathogen burden was higher in the cecum and colon. Confocal laser scanning microscopy revealed that C. difficile bacteria were distributed heterogeneously over the intestinal tissue, without contact with epithelial cells. The R20291 strain, which belongs to the Ribotype 027 lineage, displayed a unique behavior compared to the other strains by forming numerous aggregates. By immunochemistry analyses, we showed that bacteria were localized inside and outside the mucus layer, irrespective of the strains tested. Most bacteria were entrapped in 3-D structures overlaying the mucus layer. For the R20291 strain, the cell-wall associated polysaccharide PS-II was detected in large amounts in the 3-D structure. As this component has been detected in the extrapolymeric matrix of in vitro C. difficile biofilms, our data suggest strongly that at least the R20291 strain is organized in the mono-associated mouse model in glycan-rich biofilm architecture, which sustainably maintains bacteria outside the mucus layer.
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Affiliation(s)
- Anna P Soavelomandroso
- EA4043, Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Françoise Gaudin
- Institut Paris Saclay d'Innovation Thérapeutique (IPSIT), UMS IPSIT Université Paris-Sud - US 31 INSERM - UMS 3679 CNRS, Plateforme d'Histologie souris Immunopathologie de Clamart - PHIC, Clamart, France
| | - Sandra Hoys
- EA4043, Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Valérie Nicolas
- Institut Paris Saclay d'Innovation Thérapeutique (IPSIT), UMS IPSIT Université Paris-Sud - US 31 INSERM - UMS 3679 CNRS, Plateforme d'Imagerie cellulaire - MIPSIT, Châtenay-Malabry, France
| | - Gayatri Vedantam
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ, United States
| | - Claire Janoir
- EA4043, Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Sylvie Bouttier
- EA4043, Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
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16
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Kint N, Janoir C, Monot M, Hoys S, Soutourina O, Dupuy B, Martin-Verstraete I. The alternative sigma factor σ B plays a crucial role in adaptive strategies of Clostridium difficile during gut infection. Environ Microbiol 2017; 19:1933-1958. [PMID: 28198085 DOI: 10.1111/1462-2920.13696] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/19/2017] [Accepted: 01/22/2017] [Indexed: 12/29/2022]
Abstract
Clostridium difficile is a major cause of diarrhoea associated with antibiotherapy. Exposed to stresses in the gut, C. difficile can survive by inducing protection, detoxification and repair systems. In several firmicutes, most of these systems are controlled by the general stress response involving σB . In this work, we studied the role of σB in the physiopathology of C. difficile. We showed that the survival of the sigB mutant during the stationary phase was reduced. Using a transcriptome analysis, we showed that σB controls the expression of ∼25% of genes including genes involved in sporulation, metabolism, cell surface biogenesis and the management of stresses. By contrast, σB does not control toxin gene expression. In agreement with the up-regulation of sporulation genes, the sporulation efficiency is higher in the sigB mutant than in the wild-type strain. sigB inactivation also led to increased sensitivity to acidification, cationic antimicrobial peptides, nitric oxide and ROS. In addition, we showed for the first time that σB also plays a crucial role in oxygen tolerance in this strict anaerobe. Finally, we demonstrated that the fitness of colonisation by the sigB mutant is greatly affected in a dixenic mouse model of colonisation when compared to the wild-type strain.
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Affiliation(s)
- Nicolas Kint
- Laboratoire Pathogénese des Bactéries Anaérobies, Institut Pasteur, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Claire Janoir
- EA 4043, Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290, Châtenay-Malabry, France
| | - Marc Monot
- Laboratoire Pathogénese des Bactéries Anaérobies, Institut Pasteur, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Sandra Hoys
- EA 4043, Unité Bactéries Pathogènes et Santé (UBaPS), Université Paris-Sud, Université Paris-Saclay, 92290, Châtenay-Malabry, France
| | - Olga Soutourina
- Laboratoire Pathogénese des Bactéries Anaérobies, Institut Pasteur, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Bruno Dupuy
- Laboratoire Pathogénese des Bactéries Anaérobies, Institut Pasteur, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Isabelle Martin-Verstraete
- Laboratoire Pathogénese des Bactéries Anaérobies, Institut Pasteur, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Paris, France
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17
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Abstract
INTRODUCTION Clostridium difficile infections are characterized by a high recurrence rate despite antibiotic treatments and there is an urgent need to develop new treatments such as fecal transplantation and immonotherapy. Besides active immunotherapy with vaccines, passive immunotherapy has shown promise, especially with monoclonal antibodies. Areas covered: Herein, the authors review the different assays performed with monoclonal antibodies against C. difficile toxins and surface proteins to treat or prevent primary or recurrent episodes of C. difficile infection in animal models and in clinical trials as well. Notably, the authors lay emphasis on the phase III clinical trial (MODIFY II), which allowed bezlotoxumab to be approved by the Food and Drug Administration and the European Medicines Agency. They also review new strategies for producing single domain antibodies and nanobodies against C. difficile and new approaches to deliver them in the digestive tract. Expert opinion: Only two human Mabs against TcdA and TcdB have been tested alone or in combination in clinical trials. However, many animal model studies have provided rationale for the use of Mabs and nanobodies in C. difficile infection and pave the way for further clinical investigation.
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Affiliation(s)
- Séverine Péchiné
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
| | - Claire Janoir
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
| | - Anne Collignon
- a EA4043 Faculté de Pharmacie , Univ Paris-Sud, Université Paris-Saclay , Chatenay-Malabry , France
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Kansau I, Barketi-Klai A, Monot M, Hoys S, Dupuy B, Janoir C, Collignon A. Deciphering Adaptation Strategies of the Epidemic Clostridium difficile 027 Strain during Infection through In Vivo Transcriptional Analysis. PLoS One 2016; 11:e0158204. [PMID: 27351947 PMCID: PMC4924792 DOI: 10.1371/journal.pone.0158204] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 06/13/2016] [Indexed: 01/05/2023] Open
Abstract
Clostridium difficile is responsible for a wide spectrum of infection from asymptomatic carriage to severe, relapsing colitis. Since 2003, C. difficile infections have increased with a higher morbidity and mortality due to the emergence of epidemic and hypervirulent C. difficile strains such as those of the epidemic lineage 027/BI/NAP1. To decipher the hypervirulence and epidemicity of 027 strains, we analyzed gene expression profiles of the R20291 027 strain using a monoxenic mouse model during the first 38h of infection. A total of 741 genes were differentially expressed during the course of infection. They are mainly distributed in functional categories involved in host adaptation. Several genes of PTS and ABC transporters were significantly regulated during the infection, underlying the ability of strain R20291 to adapt its metabolism according to nutrient availability in the digestive tract. In this animal model, despite the early sporulation process, sporulation efficiency seems to indicate that growth of R20291 vegetative cells versus spores were favored during infection. The bacterial mechanisms associated to adaptability and flexibility within the gut environment, in addition to the virulence factor expression and antibiotic resistance, should contribute to the epidemicity and hypervirulence of the C. difficile 027 strains.
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Affiliation(s)
- Imad Kansau
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, 92296, Châtenay-Malabry Cedex, France
| | - Amira Barketi-Klai
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, 92296, Châtenay-Malabry Cedex, France
| | - Marc Monot
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, 25–28, rue du Docteur Roux, 75015, Paris, France
| | - Sandra Hoys
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, 92296, Châtenay-Malabry Cedex, France
| | - Bruno Dupuy
- Laboratoire Pathogenèse des Bactéries Anaérobies, Institut Pasteur, 25–28, rue du Docteur Roux, 75015, Paris, France
| | - Claire Janoir
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, 92296, Châtenay-Malabry Cedex, France
| | - Anne Collignon
- EA4043 Unité Bactéries Pathogènes et Santé (UBaPS), Univ. Paris-Sud, Université Paris-Saclay, 92296, Châtenay-Malabry Cedex, France
- * E-mail:
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Janoir C, Lepoutre A, Gutmann L, Varon E. Insight Into Resistance Phenotypes of Emergent Non 13-valent Pneumococcal Conjugate Vaccine Type Pneumococci Isolated From Invasive Disease After 13-valent Pneumococcal Conjugate Vaccine Implementation in France. Open Forum Infect Dis 2016; 3:ofw020. [PMID: 26955644 PMCID: PMC4777900 DOI: 10.1093/ofid/ofw020] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/28/2016] [Indexed: 11/13/2022] Open
Abstract
Background. In 2010, the pneumococcal 13-valent conjugate vaccine (PCV13), containing 6 additional serotypes including the multidrug-resistant 19A, replaced the PCV7 in France. This study aimed at analyzing trends in antibiotic resistance in invasive pneumococcal disease (IPD) isolates in France after PCV13 introduction. Methods. A total of 5243 pneumococci isolated from IPD in 2008-2009 (late PCV7 era) and 2011-2012 (PCV13 era) were studied according to their serotype and antibiotic resistance profile. Multilocus sequence typing analysis was performed on strains of the predominant serotypes (12F and 24F) isolated from young children. Results. Overall, the prevalence of antibiotic resistance decreased in France (-21.5% for penicillin from 2008-2009 to 2011-2012), mainly driven by the decline of the 19A serotype. Among non-PCV13 serotypes that concomitantly emerged, serotypes 12F, 24F, 15A, and 35B were consistently associated with resistance to 1 or more antibiotics. In children under 2 years, serotypes 15A, 35B, and 24F accounted together for 37.8% and 31.9% of penicillin-nonsusceptible and erythromycin-resistant isolates, respectively. Chloramphenicol and cotrimoxazole resistance were mainly associated with serotypes 12F and 24F, respectively. Genetic analysis showed that although emergence of serotype 12F pneumococci resulted from the expansion of various pre-existing lineages, increase in serotype 24F was related to the clonal expansion of the ST162 penicillin-susceptible cotrimoxazole-resistant lineage. Conclusions. We showed that decline of PCV13-related IPD was associated with a decline in antibiotic resistance in France, but that it likely favored the spread of several resistant nonvaccine serotypes. However, antibiotic resistance does not seem to be the only element that may drive this phenomenon.
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Affiliation(s)
- Claire Janoir
- Centre National de Référence des Pneumocoques, Laboratoire de Microbiologie, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou; EA 4043, Unité Bactéries Pathogènes et Santé, Université Paris-Saclay, Université Paris-Sud, Châtenay-Malabry
| | | | - Laurent Gutmann
- Centre National de Référence des Pneumocoques, Laboratoire de Microbiologie, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou
| | - Emmanuelle Varon
- Centre National de Référence des Pneumocoques, Laboratoire de Microbiologie, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou
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20
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Janoir C. Virulence factors of Clostridium difficile and their role during infection. Anaerobe 2016; 37:13-24. [DOI: 10.1016/j.anaerobe.2015.10.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/16/2015] [Accepted: 10/21/2015] [Indexed: 02/08/2023]
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Janoir C, Cohen R, Levy C, Bingen E, Lepoutre A, Gutmann L, Varon E. Clonal expansion of the macrolide resistant ST386 within pneumococcal serotype 6C in France. PLoS One 2014; 9:e90935. [PMID: 24603763 PMCID: PMC3946248 DOI: 10.1371/journal.pone.0090935] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 02/04/2014] [Indexed: 11/19/2022] Open
Abstract
In France, the use of the 7-valent pneumococcal conjugate vaccine (PCV7) lead to an overall significant decrease in PCV7 invasive pneumococcal disease (IPD) incidence. However, the decrease in vaccine serotype prevalence was partially counterbalanced by the serotype replacement phenomenon. In this study, we analyzed the role of the newly described serotype 6C as one of the replacement serotypes. This work was conducted on a large time scale from the early PCV7 era (2002-2003) to the PCV13 era (2010-2011), both on IPD strains recovered from the whole population and nasopharyngeal colonizing strains isolated in infant less than two years, who are known to be the main reservoir for pneumococci. Serotype 6C took advantage over 6A and 6B serotypes, which both decreased over time. A continuous and significant increase in 6C IPD was observed in adults along the study period; in contrast, in children less than two years, only an increase in 6C nasopharyngeal carriage was found, the prevalence of serotype 6C in IPD remaining very low over time. Among 101 6C invasive and colonizing strains studied by MLST, 24 STs were found to be related to three major clonal complexes, CC395, CC176, and CC315. STs related to CC176 tend to disappear after 2009 and were essentially replaced by ST386 (CC315), which dramatically increased over time. This clonal expansion may be explained by the erythromycin and tetracycline resistances associated with this clone. Finally, the decrease observed in nasopharyngeal 6C carriage since 2010, likely related to the PCV13 introduction in the French immunization schedule, is expected to lead to a decrease in 6C IPD in adults thereafter.
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Affiliation(s)
- Claire Janoir
- Centre National de Référence des Pneumocoques (CNRP), AP-HP Hôpital Européen Georges-Pompidou, Paris, France
- Département de Microbiologie, Faculté de Pharmacie EA4043, Châtenay-Malabry, France
| | - Robert Cohen
- Département de Microbiologie, Centre Hospitalier Intercommunal de Créteil, Créteil, France
- Centre de Recherche Clinique, Centre Hospitalier Intercommunal de Créteil, Créteil, France
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Saint-Maur-des-Fossés, France
- Groupe de Pathologie Infectieuse Pédiatrique (GPIP), Paris, France
| | - Corinne Levy
- Centre de Recherche Clinique, Centre Hospitalier Intercommunal de Créteil, Créteil, France
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Saint-Maur-des-Fossés, France
- Groupe de Pathologie Infectieuse Pédiatrique (GPIP), Paris, France
| | - Edouard Bingen
- Groupe de Pathologie Infectieuse Pédiatrique (GPIP), Paris, France
- Département de Microbiologie, Université Denis-Diderot-Paris 7, AP-HP Hôpital Robert-Debré, Paris, France
| | - Agnès Lepoutre
- Département de Maladies Infectieuses, Institut de Veille Sanitaire, Saint-Maurice, France
| | - Laurent Gutmann
- Centre National de Référence des Pneumocoques (CNRP), AP-HP Hôpital Européen Georges-Pompidou, Paris, France
- Laboratoire de Microbiologie, AP-HP Hôpital Européen Georges-Pompidou, Paris, France
- INSERM, U872, Paris, France
| | - Emmanuelle Varon
- Centre National de Référence des Pneumocoques (CNRP), AP-HP Hôpital Européen Georges-Pompidou, Paris, France
- Laboratoire de Microbiologie, AP-HP Hôpital Européen Georges-Pompidou, Paris, France
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Chapetón Montes D, Collignon A, Janoir C. Influence of environmental conditions on the expression and the maturation process of the Clostridium difficile surface associated protease Cwp84. Anaerobe 2013; 19:79-82. [DOI: 10.1016/j.anaerobe.2012.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 10/31/2012] [Accepted: 12/06/2012] [Indexed: 10/27/2022]
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23
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Sandolo C, Péchiné S, Le Monnier A, Hoys S, Janoir C, Coviello T, Alhaique F, Collignon A, Fattal E, Tsapis N. Encapsulation of Cwp84 into pectin beads for oral vaccination against Clostridium difficile. Eur J Pharm Biopharm 2011; 79:566-73. [DOI: 10.1016/j.ejpb.2011.05.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 05/19/2011] [Accepted: 05/24/2011] [Indexed: 11/27/2022]
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24
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Péchiné S, Denève C, Le Monnier A, Hoys S, Janoir C, Collignon A. Immunization of hamsters againstClostridium difficileinfection using the Cwp84 protease as an antigen. ACTA ACUST UNITED AC 2011; 63:73-81. [DOI: 10.1111/j.1574-695x.2011.00832.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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25
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Grohs P, Janoir C, Grondin S, Simon S, Bonnet G, Henry L, Gutmann L, Varon E. Accuracy of MIC determination for Streptococcus pneumoniae using the Sirscan2000automatic MIC determination system. Diagn Microbiol Infect Dis 2011; 70:399-403. [DOI: 10.1016/j.diagmicrobio.2011.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 02/25/2011] [Accepted: 03/02/2011] [Indexed: 11/28/2022]
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Fagan RP, Janoir C, Collignon A, Mastrantonio P, Poxton IR, Fairweather NF. A proposed nomenclature for cell wall proteins of Clostridium difficile. J Med Microbiol 2011; 60:1225-1228. [PMID: 21252271 DOI: 10.1099/jmm.0.028472-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Strains of Clostridium difficile produce a number of surface-localized proteins, including the S-layer proteins (SLPs) and other proteins that have suspected roles in pathogenesis. During the Third International C. difficile Symposium (Bled, Slovenia, September 2010) discussions were held on standardization of nomenclature. Gene designations were proposed for the large family of cell wall proteins that are paralogues of the SLP and contain putative cell wall binding motifs. This paper summarizes the agreed nomenclature, which we hope will be used by research groups currently active in the field.
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Affiliation(s)
- Robert P Fagan
- Division of Cell and Molecular Biology, Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Claire Janoir
- Université de Paris-Sud XI, USC INRA EA 4043, Faculté de Pharmacie, Châtenay-Malabry Cedex, France
| | - Anne Collignon
- Université de Paris-Sud XI, USC INRA EA 4043, Faculté de Pharmacie, Châtenay-Malabry Cedex, France
| | - Paola Mastrantonio
- Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
| | - Ian R Poxton
- Medical Microbiology, Centre for Infectious Diseases, University of Edinburgh College of Medicine and Veterinary Medicine, Edinburgh EH16 4SB, UK
| | - Neil F Fairweather
- Division of Cell and Molecular Biology, Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK
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27
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Dang THT, Riva LDL, Fagan RP, Storck EM, Heal WP, Janoir C, Fairweather NF, Tate EW. Chemical probes of surface layer biogenesis in Clostridium difficile. ACS Chem Biol 2010; 5:279-85. [PMID: 20067320 DOI: 10.1021/cb9002859] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Clostridium difficile, a leading cause of hospital-acquired infection, possesses a dense surface layer (S-layer) that mediates host-pathogen interactions. The key structural components of the S-layer result from proteolytic cleavage of a precursor protein, SlpA, into high- and low-molecular-weight components. Here we report the discovery and optimization of the first inhibitors of this process in live bacteria and their application for probing S-layer processing. We also describe the design and in vivo application of activity-based probes that identify the protein Cwp84 as the cysteine protease that mediates SlpA cleavage. This work provides novel chemical tools for the analysis of S-layer biogenesis and for the potential identification of novel drug targets within clostridia and related bacterial pathogens.
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Affiliation(s)
| | - Lucia de la Riva
- Department of Chemistry
- Centre for Molecular Microbiology and Infection, Department of Life Sciences, Imperial College London, Exhibition Rd., London SW7 2AZ, U.K
| | - Robert P. Fagan
- Centre for Molecular Microbiology and Infection, Department of Life Sciences, Imperial College London, Exhibition Rd., London SW7 2AZ, U.K
| | | | | | - Claire Janoir
- EA 4043, Université Paris-Sud 11, Faculté de Pharmacie, 92296 Châtenay-Malabry, France
| | - Neil F. Fairweather
- Centre for Molecular Microbiology and Infection, Department of Life Sciences, Imperial College London, Exhibition Rd., London SW7 2AZ, U.K
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Abstract
The disease spectrum caused by Clostridium difficile infection ranges from antibiotic-associated diarrhoea to life-threatening clinical manifestations such as pseudomembranous colitis. C. difficile infection is precipitated by antimicrobial therapy that causes a disruption of the normal colonic microbiota, predisposing to C. difficile intestinal colonisation. The pathogenicity of C. difficile is mediated by two exotoxins, TcdA and TcdB, both of which damage the human colonic mucosa and are potent cytotoxic enzymes. C. difficile must first be implanted in the gut and attach to epithelial cells, which are protected by a layer of dense mucus. Confirmed and putative accessory virulence factors that could play a role in adherence and intestinal colonisation have been identified and include proteolytic enzymes and adhesins. Recently, the epidemiology of C. difficile infection has radically changed and an increased incidence is associated with outbreaks in North America and Europe. Several reports suggest that disease severity is increasing to include sepsis syndrome and toxin megacolon. Elderly, debilitated patients in hospitals and nursing homes are particularly vulnerable. A hypervirulent, epidemic strain has been associated with the changing epidemiology and severity of disease. Here, we review the characteristics of the epidemic NAP1, PCR ribotype 027 C. difficile strain that could explain its hypervirulence and epidemic spread.
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Affiliation(s)
- C Denève
- EA 4043, Université Paris-Sud, Châtenay-Malabry, France
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29
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Denève C, Deloménie C, Barc MC, Collignon A, Janoir C. Antibiotics involved in Clostridium difficile-associated disease increase colonization factor gene expression. J Med Microbiol 2008; 57:732-738. [PMID: 18480330 DOI: 10.1099/jmm.0.47676-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Clostridium difficile is the most common cause of antibiotic-associated diarrhoea. Antibiotics are presumed to disturb the normal intestinal microbiota, leading to depletion of the barrier effect and colonization by pathogenic bacteria. This first step of infection includes adherence to epithelial cells. We investigated the impact of various environmental conditions in vitro on the expression of genes encoding known, or putative, colonization factors: three adhesins, P47 (one of the two S-layer proteins), Cwp66 and Fbp68, and a protease, Cwp84. The conditions studied included hyperosmolarity, iron depletion and exposure to several antibiotics (ampicillin, clindamycin, ofloxacin, moxifloxacin and kanamycin). The analysis was performed on three toxigenic and three non-toxigenic C. difficile isolates using real-time PCR. To complete this work, the impact of ampicillin and clindamycin on the adherence of C. difficile to Caco-2/TC7 cells was analysed. Overall, for the six strains of C. difficile studied, exposure to subinhibitory concentrations (1/2 MIC) of clindamycin and ampicillin led to the increased expression of genes encoding colonization factors. This was correlated with the increased adherence of C. difficile to cultured cells under the same conditions. The levels of gene regulation observed among the six strains studied were highly variable, cwp84 being the most upregulated. In contrast, the expression of these genes was weakly, or not significantly, modified in the presence of ofloxacin, moxifloxacin or kanamycin. These results suggest that, in addition to the disruption of the normal intestinal microbiota and its barrier effect, the high propensity of antibiotics such as ampicillin and clindamycin to induce C. difficile infection could also be explained by their direct role in enhancing colonization by C. difficile.
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Affiliation(s)
- Cécile Denève
- Université Paris Sud-XI, USC INRA 4043, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Claudine Deloménie
- Université Paris Sud-XI, IFR 141, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Marie-Claude Barc
- Université Paris Sud-XI, USC INRA 4043, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Anne Collignon
- AP-HP, Laboratoire de Microbiologie, Hôpital Jean Verdier, Bondy, France.,Université Paris Sud-XI, USC INRA 4043, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Claire Janoir
- Université Paris Sud-XI, USC INRA 4043, Faculté de Pharmacie, Châtenay-Malabry, France
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Janoir C, Péchiné S, Grosdidier C, Collignon A. Cwp84, a surface-associated protein of Clostridium difficile, is a cysteine protease with degrading activity on extracellular matrix proteins. J Bacteriol 2007; 189:7174-80. [PMID: 17693508 PMCID: PMC2168428 DOI: 10.1128/jb.00578-07] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clostridium difficile pathogenicity is mediated mainly by its A and B toxins, but the colonization process is thought to be a necessary preliminary step in the course of infection. The aim of this study was to characterize the Cwp84 protease of C. difficile, which is highly immunogenic in patients with C. difficile-associated disease and is potentially involved in the pathogenic process. Cwp84 was purified as a recombinant His-tagged protein, and specific antibodies were generated in rabbits. Treatment of multiple-band-containing eluted fractions with a reducing agent or with trypsin led to accumulation of a unique protein species with an estimated molecular mass of 61 kDa, corresponding most likely to mature autoprocessed Cwp84 (mCwp84). mCwp84 showed concentration-dependent caseinolytic activity, with maximum activity at pH 7.5. The Cwp84 activity was inhibited by various cysteine protease inhibitors, such as the specific inhibitor E64, and the anti-Cwp84-specific antibodies. Using fractionation experiments followed by immunoblot detection, the protease was found to be associated with the S-layer proteins, mostly as a nonmature species. Proteolytic assays were performed with extracellular matrix proteins to assess the putative role of Cwp84 in the pathogenicity of C. difficile. No degrading activity was detected with type IV collagen. In contrast, Cwp84 exhibited degrading activity with fibronectin, laminin, and vitronectin, which was neutralized by the E64 inhibitor and specific antibodies. In vivo, this proteolytic activity could contribute to the degradation of the host tissue integrity and to the dissemination of the infection.
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Affiliation(s)
- Claire Janoir
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clément, 92296, Châtenay-Malabry Cedex, France
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31
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Péchiné S, Janoir C, Boureau H, Gleizes A, Tsapis N, Hoys S, Fattal E, Collignon A. Diminished intestinal colonization by Clostridium difficile and immune response in mice after mucosal immunization with surface proteins of Clostridium difficile. Vaccine 2007; 25:3946-54. [PMID: 17433506 DOI: 10.1016/j.vaccine.2007.02.055] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 01/17/2007] [Accepted: 02/20/2007] [Indexed: 01/30/2023]
Abstract
Clostridium difficile pathogenesis is mainly due to toxins A and B. However, the first step of pathogenesis is the colonization process. We evaluated C. difficile surface proteins as vaccine antigens to diminish intestinal colonization in a human flora-associated mouse model. First, we used the flagellar cap protein FliD of C. difficile, in order to test several immunization routes: intranasal, rectal, and intragastric. The rectal route, which is the most efficient, was used to vaccine groups of mice with different antigen combinations. After immunizations, the mice were challenged with the toxigenic C. difficile and a significant statistical difference between the control group and the immunized groups was observed in the colonization levels of C. difficile.
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Affiliation(s)
- Séverine Péchiné
- Université de Paris-Sud, Faculté de Pharmacie, EA 4043, USC INRA, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France.
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Poilane I, Humeniuk-Ainouz C, Durand I, Janoir C, Cruaud P, Delmée M, Popoff MR, Collignon A. Molecular characterization of Clostridium difficile clinical isolates in a geriatric hospital. J Med Microbiol 2007; 56:386-390. [PMID: 17314371 DOI: 10.1099/jmm.0.46608-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The discriminatory potential of a combination of various typing methods was evaluated on a set of 21 Clostridium difficile isolates obtained from symptomatic patients hospitalized in a geriatric unit and 7 non-toxigenic isolates from the same hospital. Isolates were firstly serotyped and toxinotyped. Of the 28 isolates, 19 belonged to serogroup A. PCR-ribotyping and PCR-RFLP on the fliC and slpA genes were then applied to these 19 isolates. The results suggest that the combination of PCR-ribotyping with PCR-RFLP analysis of slpA could be more discriminatory and suitable for studying C. difficile epidemiology.
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Affiliation(s)
- Isabelle Poilane
- AP-HP, Hôpital Jean Verdier-René Muret, Service de Microbiologie, Bondy, France
| | | | - Isabelle Durand
- AP-HP, Hôpital Jean Verdier-René Muret, Service de Microbiologie, Bondy, France
| | - Claire Janoir
- Université de Paris-Sud-XI, Faculté de Pharmacie, USC INRA EA3534, Châtenay-Malabry, France
| | - Philippe Cruaud
- AP-HP, Hôpital Jean Verdier-René Muret, Service de Microbiologie, Bondy, France
| | - Michel Delmée
- Université Catholique de Louvain, Unité de Microbiologie, Brussels, Belgium
| | - Michel R Popoff
- Institut Pasteur, Unité des Bactéries Anaérobies et du Botulisme, Paris, France
| | - Anne Collignon
- Université de Paris-Sud-XI, Faculté de Pharmacie, USC INRA EA3534, Châtenay-Malabry, France
- AP-HP, Hôpital Jean Verdier-René Muret, Service de Microbiologie, Bondy, France
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Péchiné S, Janoir C, Collignon A. Variability of Clostridium difficile surface proteins and specific serum antibody response in patients with Clostridium difficile-associated disease. J Clin Microbiol 2005; 43:5018-25. [PMID: 16207956 PMCID: PMC1248434 DOI: 10.1128/jcm.43.10.5018-5025.2005] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Pathogen attachment is a crucial early step in mucosal infections. This step is mediated by important virulence factors, such as surface proteins. Clostridium difficile surface proteins have been identified as (i) adhesins (the flagellar cap protein FliD; the flagellin FliC; and the cell wall protein Cwp 66 with a two domain-structure [Cw 66 N-terminal and Cwp 66 C-terminal domains]) and (ii) protease (the Cwp 84 protein). To address the roles of these proteins in the pathogenesis of Clostridium difficile and to identify vaccine antigen candidates, we analyzed the variability of the proteins and their immunogenicities in 17 patients with C. difficile-associated disease. PCR-restriction fragment length polymorphism analysis of amplified gene products revealed interstrain homogeneity with fliC and fliD, in contrast to cwp 66 genes. Immunoblot analysis showed that FliC and FliD were detected in the majority of isolates. The N-terminal domain of Cwp 66 and Cwp 84 were present in all strains tested, in contrast to the Cwp 66 C-terminal domain, the expression of which was heterogeneous. The 17 sera from the corresponding patients were analyzed by enzyme-linked immunosorbent assay to detect antibodies directed against these proteins. Many patients developed antibodies to FliC, FliD, Cwp 84, and the Cwp 66 C-terminal domain, but not to the Cwp 66 N-terminal domain. In conclusion, this study confirms the expression of these surface proteins of C. difficile during the course of the disease. In addition, the FliC, FliD, and Cwp 84 proteins appeared to be good potential vaccine candidates.
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Affiliation(s)
- Séverine Péchiné
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clément, F-92296 Chātenay-Malabry cedex, France
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Péchiné S, Gleizes A, Janoir C, Gorges-Kergot R, Barc MC, Delmée M, Collignon A. Immunological properties of surface proteins of Clostridium difficile. J Med Microbiol 2005; 54:193-196. [PMID: 15673516 DOI: 10.1099/jmm.0.45800-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sera from patients with Clostridium difficile-associated disease (CDAD) and sera from a control group were analysed by an ELISA to detect antibodies directed against four surface proteins and toxins A and B of C. difficile. The surface proteins were the flagellar cap protein FliD, the flagellin FliC, the adhesin Cwp66 divided into two domains, Cwp66-Nterminal and Cwp66-Cterminal, and the fibronectin-binding protein Fbp68. For each antigen, antibody levels in the CDAD patient group and in the control group were compared. In the CDAD patient group, the mean of the antibody levels decreased from Cwp66-Cterminal to Fbp68, FliD, toxins B and A, Cwp66-Nterminal and finally FliC, suggesting different immunogenic properties among these adhesins. For Cwp66-Nterminal, FliC, FliD and Fbp68, the antibody level observed in the control group was higher than in the CDAD group with a statistically significant difference whereas the antibody level for toxins A and B was not statistically different. In conclusion, this study suggests that during the clinical course of disease, C. difficile adhesins are able to induce an immune response which could play a role in the defence mechanism of the host.
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Affiliation(s)
- Séverine Péchiné
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Aude Gleizes
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Claire Janoir
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Roseline Gorges-Kergot
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Marie-Claude Barc
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Michel Delmée
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
| | - Anne Collignon
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, 5 rue JB Clement, F-92296 Châtenay-Malabry cedex, France 2Université Catholique de Louvain, Faculté de Médecine, Unité de Microbiologie, Avenue Hippocrate 54.90, Bruxelles 1200, Belgium
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Janoir C, Grénery J, Savariau-Lacomme MP, Collignon A. [Characterization of an extracellular protease from Clostridium difficile]. ACTA ACUST UNITED AC 2004; 52:444-9. [PMID: 15465262 DOI: 10.1016/j.patbio.2004.07.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2004] [Accepted: 07/15/2004] [Indexed: 11/22/2022]
Abstract
Clostridium difficile is an intestinal pathogen, which produces two main virulence factors, the exotoxins A and B. Other bacterial structures have been implicated in the colonization of the gastrointestinal tract, which is the first step of the pathogenic process. C. difficile expresses adherence factors and also, displays some surface-associated proteolytic activity, which could play a role in the physiopathology of this bacterium. The aim of this work was to study the protein named Cwp84 which displays significant homologies with many cysteine proteases. The coding catalytic domain of this protein has been cloned in the expression system pGEX-6P-1, as an in-frame fusion with the gluthatione S-transferase, and subsequently purified. The purified fraction showed proteolytic activity on gelatine and BAPNA, but not on azocoll, suggesting a highly selective substrate specificity. The results obtained from inhibition experiments confirmed that Cwp84 belongs to the cysteine protease family. Cwp84 could play a role in degrading some specific host proteins or in the maturation of surface-associated bacterial proteins.
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Affiliation(s)
- C Janoir
- Département de microbiologie-EA 3534, faculté de pharmacie, université de Paris Sud, 5, rue Jean-Baptiste-Clément, 92296 Châtenay-Malabry cedex, France.
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Barc MC, Bourlioux F, Rigottier-Gois L, Charrin-Sarnel C, Janoir C, Boureau H, Doré J, Collignon A. Effect of amoxicillin-clavulanic acid on human fecal flora in a gnotobiotic mouse model assessed with fluorescence hybridization using group-specific 16S rRNA probes in combination with flow cytometry. Antimicrob Agents Chemother 2004; 48:1365-8. [PMID: 15047545 PMCID: PMC375311 DOI: 10.1128/aac.48.4.1365-1368.2004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Predominant groups of bacteria from a human fecal flora-associated mouse model challenged with amoxicillin-clavulanic acid were quantified with fluorescence in situ hybridization combined with flow cytometry using specific 16S rRNA targeted oligonucleotide probes. This approach provides a useful tool with high throughput to evaluate fecal microflora under antibiotic treatment.
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Affiliation(s)
- Marie Claude Barc
- Unité associée INRA Ecosystème Microbien Digestif et Santé, Faculté de Pharmacie, Université Paris-Sud, 92296 Châtenay-Malabry Cedex, France
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Hennequin C, Janoir C, Barc MC, Collignon A, Karjalainen T. Identification and characterization of a fibronectin-binding protein from Clostridium difficile. Microbiology 2003; 149:2779-2787. [PMID: 14523111 DOI: 10.1099/mic.0.26145-0] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A 68 kDa fibronectin-binding protein (Fbp68) from Clostridium difficile displaying significant homology to several established or putative Fbps from other bacteria was identified. The one-copy gene is highly conserved in C. difficile isolates. Fbp68 was expressed in Escherichia coli in fusion with glutathione S-transferase; the fusion protein and the native Fbp68 were purified. Immunoblot analysis and cell fractionation experiments revealed that Fbp68 is present on the surface of the bacteria. Far-immuno dot-blotting demonstrated that Fbp68 was capable of fixing fibronectin. Indirect immunofluorescence and ELISA were employed to demonstrate that C. difficile could bind both soluble and immobilized fibronectin. With competitive adherence inhibition assays it was shown that antibodies raised against Fbp68 partially inhibited attachment of C. difficile to fibronectin and Vero cells. Furthermore, Vero cells could fix purified membrane-immobilized Fbp68. Thus Fbp68 appears to be one of the several adhesins identified to date in C. difficile.
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Affiliation(s)
- Claire Hennequin
- Département de Microbiologie, Faculté de Pharmacie, Université Paris-Sud, 5 rue JB Clément, 92296 Châtenay-Malabry cedex, France
| | - Claire Janoir
- Département de Microbiologie, Faculté de Pharmacie, Université Paris-Sud, 5 rue JB Clément, 92296 Châtenay-Malabry cedex, France
| | - Marie-Claude Barc
- Département de Microbiologie, Faculté de Pharmacie, Université Paris-Sud, 5 rue JB Clément, 92296 Châtenay-Malabry cedex, France
| | - Anne Collignon
- Département de Microbiologie, Faculté de Pharmacie, Université Paris-Sud, 5 rue JB Clément, 92296 Châtenay-Malabry cedex, France
| | - Tuomo Karjalainen
- Département de Microbiologie, Faculté de Pharmacie, Université Paris-Sud, 5 rue JB Clément, 92296 Châtenay-Malabry cedex, France
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Savariau-Lacomme MP, Lebarbier C, Karjalainen T, Collignon A, Janoir C. Transcription and analysis of polymorphism in a cluster of genes encoding surface-associated proteins of Clostridium difficile. J Bacteriol 2003; 185:4461-70. [PMID: 12867455 PMCID: PMC165755 DOI: 10.1128/jb.185.15.4461-4470.2003] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent investigations of the Clostridium difficile genome have revealed the presence of a cluster of 17 genes, 11 of which encode proteins with similar two-domain structures, likely to be surface-anchored proteins. Two of these genes have been proven to encode proteins involved in cell adherence: slpA encodes the precursor of the two proteins of the S-layer, P36 and P47, whereas cwp66 encodes the Cwp66 adhesin. To gain further insight into the function of this cluster, we further focused on slpA, cwp66, and cwp84, the latter of which encodes a putative surface-associated protein with homology to numerous cysteine proteases. It displayed nonspecific proteolytic activity when expressed as a recombinant protein in Escherichia coli. Polymorphism of cwp66 and cwp84 genes was analyzed in 28 strains, and transcriptional organization of the three genes was explored by Northern blots. The slpA gene is strongly transcribed during the entire growth phase as a bicistronic transcript; cwp66 is transcribed only in the early exponential growth phase as a polycistronic transcript encompassing the two contiguous genes upstream. The putative proteins encoded by the cotranscribed genes have no significant homology with known proteins but may have a role in adherence. No correlation could be established between sequence patterns of Cwp66 and Cwp84 and virulence of the strains. The cwp84 gene is strongly transcribed as a monocistronic message. This feature, together with the highly conserved sequence pattern of cwp84, suggests a significant role in the physiopathology of C. difficile for the Cwp84 protease, potentially in the maturation of surface-associated adhesins encoded by the gene cluster.
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Affiliation(s)
- Marie-Pierre Savariau-Lacomme
- Université de Paris-Sud, Faculté de Pharmacie, Département de Microbiologie, Unité EA 35-34, 92296 Châtenay-Malabry Cedex, France
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Abstract
For an in vitro mutant of Streptococcus pneumoniae selected on moxifloxacin four- to eightfold-increased MICs of new fluoroquinolones, only a twofold-increased MIC of ciprofloxacin, and a twofold-decreased MIC of novobiocin were observed. This phenotype was conferred by two mutations: Ser81Phe in GyrA and a novel undescribed His103Tyr mutation in ParE, outside the quinolone resistance-determining region, in the putative ATP-binding site of topoisomerase IV.
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Affiliation(s)
- C Janoir
- L.R.M.A., Université Paris VI, 75270 Paris Cedex 06, France
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Janoir C, Podglajen I, Kitzis MD, Poyart C, Gutmann L. In vitro exchange of fluoroquinolone resistance determinants between Streptococcus pneumoniae and viridans streptococci and genomic organization of the parE-parC region in S. mitis. J Infect Dis 1999; 180:555-8. [PMID: 10395882 DOI: 10.1086/314888] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Transfer of fluoroquinolone (FQ) resistance determinants between Streptococcus pneumoniae and viridans streptococci was explored by transformation in vitro. One-step FQ-resistant parC mutants were selected, and resistance could be transferred from DNA from S. oralis, S. mitis, S. sanguis, and S. constellatus to S. pneumoniae, with frequencies of 10(-3) to <10(-7) in correlation with the homologies of their quinolone resistance determining region sequences (95%, 91%, 85%, and 81%, respectively). Reciprocal transfers of mutated parC from DNA from S. pneumoniae to S. mitis and S. oralis were also observed. Simultaneous transfer of mutated parC and gyrA genes from S. mitis to S. pneumoniae yielded high-level-resistant pneumococcal transformants in one step at low frequencies. The parE-parC region of the type strain S. mitis 103335T had >90% homology with that of S. pneumoniae. The efficient interspecific transfer of quinolone resistance determinants in vitro leads us to anticipate their dissemination in the clinical setting.
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Affiliation(s)
- C Janoir
- Laboratoire de Recherche Moléculaire sur les Antibiotiques, Facultés de Médecine Broussais-Hôtel-Dieu et Pitié-Salpétrière, Université Paris VI, 75270 Paris Cedex 06, France
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Varon E, Janoir C, Kitzis MD, Gutmann L. ParC and GyrA may be interchangeable initial targets of some fluoroquinolones in Streptococcus pneumoniae. Antimicrob Agents Chemother 1999; 43:302-6. [PMID: 9925523 PMCID: PMC89068 DOI: 10.1128/aac.43.2.302] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To evaluate the role of known topoisomerase IV and gyrase mutations in the fluoroquinolone (FQ) resistance of Streptococcus pneumoniae, we transformed susceptible strain R6 with PCR-generated fragments encompassing the quinolone resistance-determining regions (QRDRs) of parC or gyrA from different recently characterized FQ-resistant mutants. Considering the MICs of FQs and the GyrA and/or ParC mutations of the individual transformants, we found three levels of resistance. The first level was obtained when a single target, ParC or GyrA, depending on the FQ, was modified. An additional mutation(s) in a second target, GyrA or ParC, led to the second level. The highest increases in resistance levels were seen for Bay y3118 and moxifloxacin with the transformant harboring a double mutation in both ParC and GyrA. When a single modified target was considered, only the ParC mutation(s) led to an increase in the MICs of pefloxacin and trovafloxacin. In contrast, the GyrA or ParC mutation(s) could lead to increases in the MICs of ciprofloxacin, sparfloxacin, grepafloxacin, Bay y3118, and moxifloxacin. These results suggest that the preferential target of trovafloxacin and pefloxacin is ParC, whereas either ParC or GyrA may both be initial targets for the remaining FQs tested. The contribution of the ParC and GyrA mutations to efflux-mediated FQ resistance was also examined. Active efflux was responsible for two- to fourfold increases in the MICs of ciprofloxacin for the transformants, regardless of the initial FQ resistance levels of the recipients.
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Affiliation(s)
- E Varon
- L.R.M.A., Université Paris VI, France
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Zeller V, Janoir C, Kitzis MD, Gutmann L, Moreau NJ. Active efflux as a mechanism of resistance to ciprofloxacin in Streptococcus pneumoniae. Antimicrob Agents Chemother 1997; 41:1973-8. [PMID: 9303396 PMCID: PMC164047 DOI: 10.1128/aac.41.9.1973] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The accumulation of fluoroquinolones (FQs) was studied in a FQ-susceptible laboratory strain of Streptococcus pneumoniae (strain R6). Uptake of FQs was not saturable, was rapidly reversible, and appeared to occur by passive diffusion. In the presence of glucose, which energizes bacteria, the uptake of FQs decreased. Inhibitors of the proton motive force and ATP synthesis increased the uptake of FQs in previously energized bacteria. Similar results were observed with the various FQs tested and may be explained to be a consequence simply of the pH gradient that exists across the cytoplasmic membrane. From a clinical susceptible strain (strain SPn5907) we isolated in vitro on ciprofloxacin an FQ-resistant mutant (strain SPn5929) for which the MICs of hydrophilic molecules were greater than those of hydrophobic molecules, and the mutant was resistant to acriflavine, cetrimide, and ethidium bromide. Strain SPn5929 showed a significantly decreased uptake of ciprofloxacin, and its determinant of resistance to ciprofloxacin was transferred by transformation to susceptible laboratory strain R6 (strain R6tr5929). No mutations in the quinolone resistance-determining regions of the gyrA and parC genes were found. In the presence of arsenate or carbonyl cyanide m-chlorophenylhydrazone, the levels of uptake of ciprofloxacin by the two resistant strains, SPn5929 and R6tr5929, reached the levels of uptake of their susceptible parents. These results suggest an active efflux of ciprofloxacin in strain SPn5929.
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Affiliation(s)
- V Zeller
- Laboratoire de Recherche Moléculaire sur les Antibiotiques, Université Paris VI, France
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Janoir C, Zeller V, Kitzis MD, Moreau NJ, Gutmann L. High-level fluoroquinolone resistance in Streptococcus pneumoniae requires mutations in parC and gyrA. Antimicrob Agents Chemother 1996; 40:2760-4. [PMID: 9124836 PMCID: PMC163617 DOI: 10.1128/aac.40.12.2760] [Citation(s) in RCA: 179] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mechanism of high-level fluoroquinolone resistance was studied in strains of Streptococcus pneumoniae, either selected in vitro or isolated from clinical samples. By using DNA from these high-level-resistant strains, low-level-resistant transformants (MIC of pefloxacin, > or = 32 micrograms/ml; MIC of ciprofloxacin, 4 micrograms/ml; MIC of sparfloxacin, 0.50 micrograms/ml) were obtained at high frequencies (ca.10(-2)), while high-level-resistant transformants (MIC of pefloxacin, > or = 64 micrograms/ml; MIC of ciprofloxacin, 16 to 64 micrograms/ml; MIC of sparfloxacin, > or = 8 micrograms/ml) were obtained only at low frequencies (ca.10(-4)). This suggested that mutations in at least two unlinked genes were necessary to obtain high-level resistance. Low-level resistance was associated with ParC mutations (change from Ser to Tyr at position 79 [Ser79Tyr], Ser79Phe, or Asp83Gly). ParC mutations were associated, in high-level-resistant strains and transformants, with alterations in the quinolone resistance-determining region of GyrA (Ser84Tyr, Ser84Phe, and/or Glu88Lys). Low-level resistance was shown to be necessary for expression of the gyrA mutations. No mutation in the region corresponding to the quinolone resistance-determining region of GyrB and no alteration of drug accumulation were found.
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Affiliation(s)
- C Janoir
- L.R.M.A., Université Paris VI, France
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