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105. Genomics of glycopeptidolipid biosynthesis in Mycobacterium abscessus and M. chelonae

Author

Etienne Gilles, Daffé Mamadou, Biet Franck, Risler Jean-Loup, Beretti Jean-Luc, Laval Françoise, Pasek Sophie, Deshayes Caroline, Ripoll Fabienne, Gaillard Jean-Louis, and Reyrat Jean-Marc

Subjects
Biotechnology, TP248.13-248.65, Genetics, QH426-470
Abstract

Abstract Background The outermost layer of the bacterial surface is of crucial importance because it is in constant interaction with the host. Glycopeptidolipids (GPLs) are major surface glycolipids present on various mycobacterial species. In the fast-grower model organism Mycobacterium smegmatis, GPL biosynthesis involves approximately 30 genes all mapping to a single region of 65 kb. Results We have recently sequenced the complete genomes of two fast-growers causing human infections, Mycobacterium abscessus (CIP 104536T) and M. chelonae (CIP 104535T). We show here that these two species contain genes corresponding to all those of the M. smegmatis "GPL locus", with extensive conservation of the predicted protein sequences consistent with the production of GPL molecules indistinguishable by biochemical analysis. However, the GPL locus appears to be split into several parts in M. chelonae and M. abscessus. One large cluster (19 genes) comprises all genes involved in the synthesis of the tripeptide-aminoalcohol moiety, the glycosylation of the lipopeptide and methylation/acetylation modifications. We provide evidence that a duplicated acetyltransferase (atf1 and atf2) in M. abscessus and M. chelonae has evolved through specialization, being able to transfer one acetyl at once in a sequential manner. There is a second smaller and distant (M. chelonae, 900 kb; M. abscessus, 3 Mb) cluster of six genes involved in the synthesis of the fatty acyl moiety and its attachment to the tripeptide-aminoalcohol moiety. The other genes are scattered throughout the genome, including two genes encoding putative regulatory proteins. Conclusion Although these three species produce identical GPL molecules, the organization of GPL genes differ between them, thus constituting species-specific signatures. An hypothesis is that the compact organization of the GPL locus in M. smegmatis represents the ancestral form and that evolution has scattered various pieces throughout the genome in M. abscessus and M. chelonae.

Published
2007
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107. Cell wall lipopeptides of Mycobacterium avium: new insights from genomics analysis

Author

Bannantine, John, Etienne, Gilles, Laval, Françoise, Lemassu, Anne, Daffé, Mamadou, Bayles, Darrell O., Ganneau, Christelle, BRANGER, Maxime, Cochard, Thierry, Stabel, Judith R., Bay, Sylvie, Biet, Franck, National Animal Disease Center, USDA, Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Fédérale Toulouse Midi-Pyrénées, Institut Pasteur [Paris], Chimie bioorganique des acides nucléiques - Bioorganic chemistry of nucleic acids, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Infectiologie et Santé Publique (UMR ISP), Institut National de la Recherche Agronomique (INRA)-Université de Tours, Société Française de Microbiologie (SFM). FRA., and Institut National de la Recherche Agronomique (INRA)-Université de Tours (UT)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology
Abstract

International audience; Mycobacteria have a complex cell wall structure that includes many lipids which are often species specific. Besides giving a phenotypic signature these lipids are often involved in infectious processes of pathogenic mycobacteria by interfering with the host immune system. The biosynthesis pathway of the simplest glycopeptidolipids (GPLs) is relatively well understood and involves more than fifteen genes. Even though M. avium subsp. paratuberculosis (Map) produces a lipopeptide rather than GPL, its genome contains nevertheless a locus highly similar to the GPL biosynthetic pathway of M. avium subsp. avium (Mav). We showed that the module composition of the non-ribosomal protein synthase (Nrp) of Map, the enzyme involved in the synthesis of the peptidyl moiety, is dramatically different from that of other GPL producers such as M. smegmatis (Ms) and Mav. While Map isolates do not produce GPLs, they do produce lipopeptides without the carbohydrate moiety. However, the picture is not as clear regarding the diversity of lipopeptides produced among two lineages classified as type I/III or S-type (ovine) and type II or C-type (bovine) Map strains that have emerged from the common ancestor, M. avium subsp. hominissuis. The S-type isolates are readily distinguishable from C-type isolates based on genome studies and readily discriminated by genotyping methods. In addition to the genotypic distinctions between S- and C-type strains, phenotypic differences have been documented. To provide a genomic basis for the synthesis of the diversity of lipopeptides in Map, its recently published genome sequence was explored using in silico methods and completed by biochemical investigations. Interestingly we discovered a change in the chemical structure of the lipopeptide of the S strains. These findings add new phenotypic evidence that contribute to separate the S type to the C type. Furthermore deciphering the biosynthesis pathway of cell wall lipopeptides should contribute to better understand the determinants of the adaptation of a pathogen to a specific host but also the factors favoring transmission to a new host.

Published
2017

111. Cell wall lipopeptides of Mycobacterium avium: new insights from genomics analysis

Author

Bannantine, John P., Etienne, Gilles, Laval, Françoise, Lemassu, Anne, Daffé, Mamadou, Bayles, Darrell O., Ganneau, Christelle, BRANGER, Maxime, Cochard, Thierry, Bay, Sylvie, Biet, Franck, United States Department of Agriculture (USDA), Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Fédérale Toulouse Midi-Pyrénées, Chimie bioorganique des acides nucléiques - Bioorganic chemistry of nucleic acids, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Infectiologie et Santé Publique (UMR ISP), Institut National de la Recherche Agronomique (INRA)-Université de Tours (UT), Institut Pasteur [Paris], Chimie organique (CNR - UMR3523), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Pasteur [Paris], Institut National de la Recherche Agronomique (INRA)-Université de Tours, International Association for Paratuberculosis. INT., Biet, Franck, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP), Chimie organique (CNRS - UMR3523), Institut Pasteur [Paris] (IP)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), and Institut Pasteur [Paris]-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, mycobacterium avium, glycopeptidolipids, lipopeptide, Cell wall, Microbiology and Parasitology, analyse génomique, non-ribosomal protein synthase, paroi cellulaire, Microbiologie et Parasitologie, ComputingMilieux_MISCELLANEOUS
Abstract

Session : Maps Genomics and Diversity; National audience; Mycobacteria have a complex cell wall structure that includes many lipids which are often species specific. Besides giving a phenotypic signature these lipids are often involved in infectious processes of pathogenic mycobacteria by interfering with the host immune system. The biosynthesis pathway of the simplest glycopeptidolipids (GPLs) is relatively well understood and involves more than fifteen genes. Even though M. avium subsp. paratuberculosis (Map) produces a lipopeptide rather than GPL, its genome contains nevertheless a locus highly similar to the GPL biosynthetic pathway of M. avium subsp. avium (Mav). We showed that the module composition of the non-ribosomal protein synthase (Nrp) of Map, the enzyme involved in the synthesis of the peptidyl moiety, is dramatically different from that of other GPL producers such as M. smegmatis (Ms) and Mav. While Map isolates do not produce GPLs, they do produce lipopeptides without the carbohydrate moiety. However, the picture is not as clear regarding the diversity of lipopeptides produced among two lineages classified as type I/III or S-type (ovine) and type II or C-type (bovine) Map strains that have emerged from the common ancestor, M. avium subsp. hominissuis. The S-type isolates are readily distinguishable from C-type isolates based on genome studies and readily discriminated by genotyping methods. In addition to the genotypic distinctions between S- and C-type strains, phenotypic differences have been documented. To provide a genomic basis for the synthesis of the diversity of lipopeptides in Map, its recently published genome sequence was explored using in silico methods and completed by biochemical investigations. Interestingly we discovered a change in the chemical structure of the lipopeptide of the S strains. These findings add new phenotypic evidence that contribute to separate the S type to the C type. Furthermore deciphering the biosynthesis pathway of cell wall lipopeptides should contribute to better understand the determinants of the adaptation of a pathogen to a specific host but also the factors favoring transmission to a new host.

Published
2016

113. Cell wall peptidolipids of Mycobacterium avium: from genetic prediction to exact structure of a nonribosomal peptide

Author

Bannantine, John P., primary, Etienne, Gilles, additional, Laval, Françoise, additional, Stabel, Judith R., additional, Lemassu, Anne, additional, Daffé, Mamadou, additional, Bayles, Darrell O., additional, Ganneau, Christelle, additional, Bonhomme, Frédéric, additional, Branger, Maxime, additional, Cochard, Thierry, additional, Bay, Sylvie, additional, and Biet, Franck, additional

Published
2017
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118. Molecular composition of the outermost capsular material of the tubercle bacillus

Author

Daffé Mamadou, Pierre Gounon, Åse Bengård Andersen, Anne Lemassu, Marie-Ange Dupont, Annick Ortalo-Magne, Laboratoire Insulaire du Vivant et de l'Environnement (LIVE), Université de la Nouvelle-Calédonie (UNC), Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Centre d'études d'océanographie et de biologie marine (CEOBM), Station biologique de Roscoff [Roscoff] (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Microscopie électronique, and Institut Pasteur [Paris] (IP)

Subjects
Lipopolysaccharides, Microscopy, Electron, Scanning Transmission, Cytoplasm, Bacilli, Magnetic Resonance Spectroscopy, mycobacteria, Tubercle, capsule, Blotting, Western, Molecular Sequence Data, polysaccharides, Context (language use), Spectrometry, Mass, Fast Atom Bombardment, Polysaccharide, Microbiology, Bacterial Proteins, Concanavalin A, Structural motif, Bacterial Capsules, Bacillus (shape), chemistry.chemical_classification, Antigens, Bacterial, Chromatography, biology, Polysaccharides, Bacterial, Mycobacterium tuberculosis, biology.organism_classification, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, Immunohistochemistry, Lipids, tuberculosis, Carbohydrate Sequence, Biochemistry, chemistry, Stress, Mechanical, Cell envelope, Bacteria
Abstract

Summary: To gain insight into the pathogenesis of tuberculosis, a molecular definition of the tubercle bacillus cell envelope, which is involved in the early stages of the infection, is required. The cell-surface-exposed material of the pathogen was isolated by mechanical means and chemically analysed. It was shown by scanning electron microscopy that the method used for extracting the surface-covering material preserves the integrity of the bacilli. Surprisingly, in view of the current opinion, only small amounts of lipids (1-6%) were present. Polysaccharides and proteins were the main components of the material. The polysaccharides were neutral and lipid-free D-glucan, D-arabino-D-mannan and D-mannan, which were eluted from gel-filtration columns in positions corresponding to molecular masses of 120, 13 and 4 kDa, respectively. Based on NMR spectroscopy and conventional chemical analyses, the major structural motifs of the purified polysaccharides were established as being identical to those of the polysaccharides we previously isolated from the culture filtrate of the tubercle bacillus. Immunocytochemical studies showed that these compounds were not only surface-located but were also present in the inner capsular compartment. The major protein constituents exhibited the same mobilities on SDS-PAGE as those of the culture filtrate of the tubercle bacillus and readily reacted with the monoclonal antibodies directed against these molecules. These proteins included the 19 and 38 kDa lipoproteins, the 30/31 kDa fibronectin-binding proteins and the 40 kDa L-alanine dehydrogenase. These findings suggest that the culture filtrate material represents part of the capsule which, in an in vivo context, could contribute to the electron transparent zone surrounding the tubercle bacillus. The 24 kDa (MPB/T64) protein was found to be a secreted protein, as it was detected almost exclusively in the culture filtrate. Taken together, the data give a new insight into the surface-exposed compounds of the tubercle bacillus and may explain part of the nature and limitation of the host immunity towards the pathogen.

Published
1995
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119. Overexpression of proinflammatory TLR-2-signalling lipoproteins in hypervirulent mycobacterial variants

Author

Roux, Anne-Laure, Ray, Aurélie, Pawlik, Alexandre, Medjahed, Halima, Etienne, Gilles, Rottman, Martin, Catherinot, Emilie, Coppée, Jean-Yves, Chaoui, Karima, Monsarrat, Bernard, Toubert, Antoine, Daffé, Mamadou, Puzo, Germain, Gaillard, Jean-Louis, Brosch, Roland, Dulphy, Nicolas, Nigou, Jérôme, Herrmann, Jean-Louis, Epidémiologie et Physiopathologie des Infections Microbiennes (EPIM), Infection et inflammation (2I), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de Microbiologie [Garches], Hôpital Raymond Poincaré [AP-HP], Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Pathogénomique mycobactérienne intégrée, Institut Pasteur [Paris] (IP), Pathogénie des infections systémiques (Inserm U1002), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Transcriptome et Epigénome (PF2), Service d'Immunologie et d'Histocompatibilité, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Paris Diderot - Paris 7 (UPD7)-Groupe Hospitalier Saint Louis - Lariboisière - Fernand Widal [Paris], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM), This work received support from the ‘Vaincre La Mucoviscidose’ Association., We greatly acknowledge Dr Ben Marshall (Southampton University Hospitals Trust, UK) for careful review of the manuscript., Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Fédérale Toulouse Midi-Pyrénées, Institut Pasteur [Paris], Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
Lipoproteins, Fluorescent Antibody Technique, MESH: Virulence, MESH: Phenotype, Polymerase Chain Reaction, Mycobacterium, Mice, MESH: Cell Membrane / immunology, MESH: Mycobacterium Infections / microbiology, MESH: Glycopeptides / metabolism, MESH: Mycobacterium Infections / immunology, Animals, Humans, MESH: Animals, MESH: Cytokines / immunology, MESH: Lipoproteins / metabolism, MESH: Fluorescent Antibody Technique, MESH: Mice, MESH: Mycobacterium / immunology, Inflammation, MESH: Inflammation / immunology, Mycobacterium Infections, [SDV.MHEP.ME]Life Sciences [q-bio]/Human health and pathology/Emerging diseases, MESH: Humans, Virulence, Macrophages, Cell Membrane, MESH: Cytokines / metabolism, Glycopeptides, MESH: Macrophages, MESH: Polymerase Chain Reaction, MESH: Toll-Like Receptor 2 / metabolism, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, Toll-Like Receptor 2, MESH: Signal Transduction, MESH: Mycobacterium / pathogenicity, MESH: Toll-Like Receptor 2 / agonists, HEK293 Cells, Phenotype, MESH: HEK293 Cells, MESH: Cytokines / biosynthesis, Cytokines, Electrophoresis, Polyacrylamide Gel, MESH: Mycobacterium / metabolism, MESH: Lipoproteins / immunology, MESH: Glycopeptides / immunology, Signal Transduction, MESH: Electrophoresis, Polyacrylamide Gel
Abstract

International audience; Changes in the cell envelope composition of mycobacteria cause major changes in cytokine profiles of infected antigen presenting cells. We describe here the modulation of inflammatory responses by Mycobacterium abscessus, an emerging pathogen in cystic fibrosis. M. abscessus is able to switch from a smooth (S) to a rough (R) morphotype by the loss of a surface glycopeptidolipid. R variants are associated with severe clinical forms and a 'hyper-proinflammatory' response in ex vivo and in vivo models. Using partitioning of cell surface components we found that a complex fraction, more abundant in R variants than in S variants, made a major contribution to the TLR-2-dependent hyper-proinflammatory response induced by R variants. Lipoproteins were the main TLR-2 agonists in this fraction, consistent with the larger amounts of 16 lipoproteins in cell surface extracts from R variants; 15 out of 16 being more strongly induced in R variant than in S variant. Genetic interruption of glycopeptidolipid pathway in wild-type S variant resulted in R phenotype with similar induction of lipoprotein genes. In conclusion, R morphotype in M. abscessus is associated with increased synthesis/exposure at the cell surface of lipoproteins, these changes profoundly modifying the innate immune response through TLR-2-dependent mechanisms.

Published
2011
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121. pks5-recombination-mediated surface remodelling in Mycobacterium tuberculosis emergence

Author

Boritsch, Eva C., primary, Frigui, Wafa, additional, Cascioferro, Alessandro, additional, Malaga, Wladimir, additional, Etienne, Gilles, additional, Laval, Françoise, additional, Pawlik, Alexandre, additional, Le Chevalier, Fabien, additional, Orgeur, Mickael, additional, Ma, Laurence, additional, Bouchier, Christiane, additional, Stinear, Timothy P., additional, Supply, Philip, additional, Majlessi, Laleh, additional, Daffé, Mamadou, additional, Guilhot, Christophe, additional, and Brosch, Roland, additional

Published
2016
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122. The Non-Essential Mycolic Acid Biosynthesis Genes hadA and hadC Contribute to the Physiology and Fitness of Mycobacterium smegmatis

Author

Jamet, Stevie, primary, Slama, Nawel, additional, Domingues, Joana, additional, Laval, Françoise, additional, Texier, Pauline, additional, Eynard, Nathalie, additional, Quémard, Annaik, additional, Peixoto, Antonio, additional, Lemassu, Anne, additional, Daffé, Mamadou, additional, and Cam, Kaymeuang, additional

Published
2015
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124. The changes in mycolic acid structures caused byhadCmutation have a dramatic effect on the virulence ofMycobacterium tuberculosis

Author

Slama, Nawel, primary, Jamet, Stevie, additional, Frigui, Wafa, additional, Pawlik, Alexandre, additional, Bottai, Daria, additional, Laval, Françoise, additional, Constant, Patricia, additional, Lemassu, Anne, additional, Cam, Kaymeuang, additional, Daffé, Mamadou, additional, Brosch, Roland, additional, Eynard, Nathalie, additional, and Quémard, Annaïk, additional

Published
2015
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125. Increased Vancomycin Susceptibility in Mycobacteria: a New Approach To Identify Synergistic Activity against Multidrug-Resistant Mycobacteria

Author

Soetaert, Karine, primary, Rens, Céline, additional, Wang, Xiao-Ming, additional, De Bruyn, Jacqueline, additional, Lanéelle, Marie-Antoinette, additional, Laval, Françoise, additional, Lemassu, Anne, additional, Daffé, Mamadou, additional, Bifani, Pablo, additional, Fontaine, Véronique, additional, and Lefèvre, Philippe, additional

Published
2015
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127. Characterization of the Mycobacterial Acyl-CoA Carboxylase Holo Complexes Reveals Their Functional Expansion into Amino Acid Catabolism

Author

Ehebauer, Matthias T., primary, Zimmermann, Michael, additional, Jakobi, Arjen J., additional, Noens, Elke E., additional, Laubitz, Daniel, additional, Cichocki, Bogdan, additional, Marrakchi, Hedia, additional, Lanéelle, Marie-Antoinette, additional, Daffé, Mamadou, additional, Sachse, Carsten, additional, Dziembowski, Andrzej, additional, Sauer, Uwe, additional, and Wilmanns, Matthias, additional

Published
2015
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128. The cyclic di-GMP phosphodiesterase geneRv1357c/BCG1419caffects BCG Pellicle production andIn Vivomaintenance

Author

Flores-Valdez, Mario Alberto, primary, de Jesús Aceves-Sánchez, Michel, additional, Pedroza-Roldán, César, additional, Vega-Domínguez, Perla Jazmín, additional, Prado-Montes de Oca, Ernesto, additional, Bravo-Madrigal, Jorge, additional, Laval, Françoise, additional, Daffé, Mamadou, additional, Koestler, Ben, additional, and Waters, Christopher M., additional

Published
2015
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135. Synthesis of lipophilic dimeric C-7/C-7-linked ciprofloxacin and C-6/C-6-linked levofloxacin derivatives. Versatile in vitro biological evaluations of monomeric and dimeric fluoroquinolone derivatives as potential antitumor, antibacterial or antimycobacterial agents.

Author

Azéma, Joëlle, Guidetti, Brigitte, Korolyov, Alexander, Kiss, Robert, Roques, Christine, Constant, Patricia, Daffé, Mamadou, Malet-Martino, Myriam, Azéma, Joëlle, Guidetti, Brigitte, Korolyov, Alexander, Kiss, Robert, Roques, Christine, Constant, Patricia, Daffé, Mamadou, and Malet-Martino, Myriam

Abstract

The synthesis of C-7/C-7-linked ciprofloxacin (CP) and C-6/C-6-linked levofloxacin (LV) derivatives with modulated lipophilicity is described herein. The synthesized compounds, along with the monomeric analogs described previously, were evaluated in vitro for (i) their growth inhibitory effect against five human cancer cell lines, (ii) their antibacterial activity against Gram-positive Staphylococcus aureus and Enterococcus hirae and Gram-negative Escherichia coli and Pseudomonas aeruginosa strains and (iii) their antimycobacterial activity. The most efficient derivatives as antiproliferative agents (C-7/C-7-linked CP 7e and C-6/C-6-linked LV 11f) displayed IC(50) values in the 0.1-8.7 and 0.2-0.7 μM ranges respectively while IC(50) values for parent CP and LV ranged from 89 to 476 μM and from 67 to 622 μM respectively depending on the cell line. A specific antibacterial activity against S. aureus was found for the monomeric and dimeric derivatives of CP. The most efficient derivative against S. aureus (monomeric oxoethyloctanoate CP derivative 3d) displayed MIC <1 nM. Monomeric alkanoyloxymethyl LV esters (9a,c,e,f) and C-6/C-6-linked LV derivatives (11f-h) were the most efficient derivatives as antimycobacterial agents with MIC and IC(50) values in the 2.5-5 μM and 1.3-≤ 2.5 μM ranges respectively while MIC and IC(50) values for parent LV were 2.5 and 0.8 μM, respectively., Journal Article, SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2011

136. Identification of a cell-wall channel in the corynemycolic acidfree gram-positive bacterium Corynebacterium amycolatum

Author

Dörner, Ursula, Schiffler, Bettina, Lanéelle, Marie-Antoinette, Daffé, Mamadou, Benz, Roland, Dörner, Ursula, Schiffler, Bettina, Lanéelle, Marie-Antoinette, Daffé, Mamadou, and Benz, Roland

Abstract

As part of a comparative study of the cell wall of corynebacteria, a channel-forming protein was characterized in Corynebacterium amycolatum, a species devoid of corynemycolic acids. Corynebacterium amycolatum cells were disrupted and the cell envelope subjected to two different separation procedures, differential centrifugation to separate the different fractions of the cell envelope, and sucrose-step-gradient density centrifugation. The fractions obtained by the two methods were analyzed for lipid composition, NADH oxidase activity, and the formation of ion-permeable channels in lipid bilayers. High channel-forming activity was always detected in fractions expected to contain only cell-wall components. The highest NADH-oxidase activity was found in other fractions, indicating that the cell-wall fraction was distinct from the membrane fraction. The cell wall was found to contain an ion-permeable channel with a single-channel conductance of about 3.8 nS in 1 M KCl. The channel-forming protein, with an apparent molecular mass of 45 kDa, was purified to homogeneity using FPLC and preparative SDS-PAGE. Single-channel experiments suggested that the cell-wall channel is wide and water-filled and has a narrow selectivity for cations. Analysis of the fatty-acid composition of extractable lipids and delipidated cells suggested that the cell wall of C. amycolatum contains enough lipids to form an additional permeability barrier on the surface of the bacteria, thus accounting for the presence of the cell-wall channel. [Int Microbiol 2009; 12(1):29-38]

Published
2010

143. Biochemical Disclosure of the Mycolate Outer Membrane of Corynebacterium glutamicum

Author

Marchand, Christophe H., primary, Salmeron, Christophe, additional, Bou Raad, Roland, additional, Méniche, Xavier, additional, Chami, Mohamed, additional, Masi, Muriel, additional, Blanot, Didier, additional, Daffé, Mamadou, additional, Tropis, Marielle, additional, Huc, Emilie, additional, Le Maréchal, Pierre, additional, Decottignies, Paulette, additional, and Bayan, Nicolas, additional

Published
2012
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145. Mycolic acids as diagnostic markers for tuberculosis case detection in humans and drug efficacy in mice

Author

Shui, Guanghou, primary, Bendt, Anne K., additional, Jappar, Ignasius A., additional, Lim, Hui Ming, additional, Laneelle, Marie, additional, Hervé, Maxime, additional, Via, Laura E., additional, Chua, Gek Huey, additional, Bratschi, Martin W., additional, Zainul Rahim, Siti Zarina, additional, Michelle, Ang Lay Teng, additional, Hwang, Soo‐Hee, additional, Lee, Jong‐Soek, additional, Eum, Seok‐Yong, additional, Kwak, Hyun‐Kyung, additional, Daffé, Mamadou, additional, Dartois, Véronique, additional, Michel, Gerd, additional, Barry, Clifton E., additional, and Wenk, Markus R., additional

Published
2011
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146. Synthesis of lipophilic dimeric C-7/C-7-linked ciprofloxacin and C-6/C-6-linked levofloxacin derivatives. Versatile in vitro biological evaluations of monomeric and dimeric fluoroquinolone derivatives as potential antitumor, antibacterial or antimycobacterial agents

Author

Azéma, Joëlle, primary, Guidetti, Brigitte, additional, Korolyov, Alexander, additional, Kiss, Robert, additional, Roques, Christine, additional, Constant, Patricia, additional, Daffé, Mamadou, additional, and Malet-Martino, Myriam, additional

Published
2011
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147. Mycobacterium tuberculosis Lineage Influences Innate Immune Response and Virulence and Is Associated with Distinct Cell Envelope Lipid Profiles

Author

Krishnan, Nitya, primary, Malaga, Wladimir, additional, Constant, Patricia, additional, Caws, Maxine, additional, Thi Hoang Chau, Tran, additional, Salmons, Jenifer, additional, Thi Ngoc Lan, Nguyen, additional, Bang, Nguyen Duc, additional, Daffé, Mamadou, additional, Young, Douglas B., additional, Robertson, Brian D., additional, Guilhot, Christophe, additional, and Thwaites, Guy E., additional

Published
2011
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148. Biochemical and immunological characterization of a cpn60.1 knockout mutant of Mycobacterium bovis BCG

Author

Wang, Xiao-Ming, primary, Lu, Changlong, additional, Soetaert, Karine, additional, S'Heeren, Catherine, additional, Peirs, Priska, additional, Lanéelle, Marie-Antoinette, additional, Lefèvre, Philippe, additional, Bifani, Pablo, additional, Content, Jean, additional, Daffé, Mamadou, additional, Huygen, Kris, additional, De Bruyn, Jacqueline, additional, and Wattiez, Ruddy, additional

Published
2011
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150. Mycobacterium leprae Phenolglycolipid-1 Expressed by Engineered M. bovis BCG Modulates Early Interaction with Human Phagocytes

Author

Tabouret, Guillaume, primary, Astarie-Dequeker, Catherine, additional, Demangel, Caroline, additional, Malaga, Wladimir, additional, Constant, Patricia, additional, Ray, Aurélie, additional, Honoré, Nadine, additional, Bello, Nana Fatimath, additional, Perez, Esther, additional, Daffé, Mamadou, additional, and Guilhot, Christophe, additional

Published
2010
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