0000000000237321
AUTHOR
Christophe D'enfert
CandidaDB: a genome database for Candida albicans pathogenomics.
CandidaDB is accessible at http://genolist.pasteur.fr/CandidaDB.; International audience; CandidaDB is a database dedicated to the genome of the most prevalent systemic fungal pathogen of humans, Candida albicans. CandidaDB is based on an annotation of the Stanford Genome Technology Center C.albicans genome sequence data by the European Galar Fungail Consortium. CandidaDB Release 2.0 (June 2004) contains information pertaining to Assembly 19 of the genome of C.albicans strain SC5314. The current release contains 6244 annotated entries corresponding to 130 tRNA genes and 5917 protein-coding genes. For these, it provides tentative functional assignments along with numerous pre-run analyses th…
Mise au point d’un modèle de co-culture cellules entérocytes et d’un modèle de colonisation digestive stable chez la souris immuno-compétente permettant d’étudier les interactions cellulaires et moléculaires in vitro et in vivo de C. albicans avec la muqueuse digestive
National audience
Rbt1 Protein Domains Analysis in Candida albicans Brings Insights into Hyphal Surface Modifications and Rbt1 Potential Role during Adhesion and Biofilm Formation
Cell wall proteins are central to the virulence of Candida albicans. Hwp1, Hwp2 and Rbt1 form a family of hypha-associated cell surface proteins. Hwp1 and Hwp2 have been involved in adhesion and other virulence traits but Rbt1 is still poorly characterized. To assess the role of Rbt1 in the interaction of C. albicans with biotic and abiotic surfaces independently of its morphological state, heterologous expression and promoter swap strategies were applied. The N-terminal domain with features typical of the Flo11 superfamily was found to be essential for adhesiveness to polystyrene through an increase in cell surface hydrophobicity. A 42 amino acid-long domain localized in the central part o…
Candida albicans interaction with M cells in an in vitro model of the human intestinal Follicle Associated Epithelium (FAE)
National audience; Candida albicans (C. albicans) is a microorganism belonging to the commensal flora of the intestinal, oral and vaginal mucosal surfaces in healthy humans. This commensalism results from a balance between the virulence factors of the yeast and defense mechanisms of the host. However, disturbance of this balance in a vulnerable patient may result in intense mucosal colonization that promotes invasion of epithelial cells, translocation across the intestinal epithelial barrier and, eventually hematogenous dissemination. A better understanding of the mechanisms by which C. albicans interacts with the intestinal mucosa will improve our knowledge of the physiopathology of dissem…
Using a Multi-Locus Microsatellite Typing method improved phylogenetic distribution of Candida albicans isolates but failed to demonstrate association of some genotype with the commensal or clinical origin of the isolates.
EA MERS CT3 Enjeu 3; International audience; The dimorphic yeast Candida albicans is a component of the normal microflora at the mucosal surfaces of healthy individuals. It possesses an array of phenotypic properties considered as virulence traits that contribute to pathogenicity of the yeast in immuno-compromised patients. We addressed the question of the pathogenicity of lineages of C. albicans with regard to their genotype in three series of C. albicans isolates (a series of commensal isolates collected in healthy individuals, a group of bloodstream isolates and a group of non-bloodstream clinical isolates) using a Multi-Locus Microsatellite Typing (MLMT) approach based on the analysis o…
Candida albicansis able to use M cells as a portal of entry across the intestinal barrierin vitro
Candida albicans is the most frequent yeast responsible for systemic infections in humans. These infections mainly originate from the gastrointestinal tract where C. albicans can invade the gut epithelial barrier to gain access to the bloodstream. Along the gut, pathogens can use Microfold (M) cells as a portal of entry to cross the epithelial barrier. M cells are specialized cells mainly located in the follicule-associated epithelium of Peyer patches. In this study, we used scanning electron and fluorescence microscopy, adhesion and invasion assays and fungal mutants to investigate the interactions of C. albicans with M cells obtained in an established in vitro model whereby enterocyte-lik…
Les cellules M : une porte d’entrée pour le franchissement de la barrière intestinale par Candida albicans
Candida albicans est un pathogene opportuniste pouvant provoquer des infections systemiques chez des patients immunodeprimes. L’origine de ces infections est principalement d’origine endogene, notamment a partir du tractus gastro-intestinal, ou le champignon peut penetrer a travers la barriere epitheliale intestinale pour gagner ensuite la circulation sanguine. Au niveau de la muqueuse intestinale, les enterocytes forment une monocouche de cellules assurant l’integrite et l’impermeabilite du tissu digestif. Au niveau des plaques de Peyer notamment, les cellules Microfold (ou cellules M) sont associees aux enterocytes et jouent un role important dans l’homeostasie digestive. En effet, ces ce…
Systematic gene overexpression in Candida albicans identifies a regulator of early adaptation to the mammalian gut.
International audience; Candida albicans is part of the human gastrointestinal (GI) microbiota. To better understand how C. albicans efficiently establishes GI colonisation, we competitively challenged growth of 572 signature-tagged strains (~10% genome coverage), each conditionally overexpressing a single gene, in the murine gut. We identified CRZ2, a transcription factor whose overexpression and deletion respectively increased and decreased early GI colonisation. Using clues from genome-wide expression and gene-set enrichment analyses, we found that the optimal activity of Crz2p occurs under hypoxia at 37°C, as evidenced by both phenotypic and transcriptomic analyses following CRZ2 geneti…