title: The cell surface-exposed glycopeptidolipids confer a selective advantage to the smooth variants of Mycobacterium smegmatis in vitro.
abstract: The cell surface of mycobacteria is quite rich in lipids. Glycopeptidolipids, surface-exposed lipids that typify some mycobacterial species, have been associated with a phenotypic switch between rough and smooth colony morphotypes. This conversion in Mycobacterium smegmatis is correlated with the absence/presence of glycopeptidolipids on the cell surface and is due to insertion sequence mobility. Here, we show that the occurrence of a high amount of glycopeptidolipids in the smooth variant leads to lower invasion abilities and lower internalization by macrophages. We further show that the high production of glycopeptidolipids on the cell surface can confer a selective advantage to the smooth variant when grown in vitro. This higher fitness under the laboratory condition might explain the selection of smooth variants in several independent laboratories. The implications of these findings are discussed.
authors.affiliation: Faculté de Médecine, Université Paris Descartes, Paris, France.
authors.forename: Dana
authors.initials: D
authors.lastname: Kocíncová
authors.forename: Nathalie
authors.initials: N
authors.lastname: Winter
authors.forename: Daniel
authors.initials: D
authors.lastname: Euphrasie
authors.forename: Mamadou
authors.initials: M
authors.lastname: Daffé
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Reyrat
authors.forename: Gilles
authors.initials: G
authors.lastname: Etienne
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology / Q000382:microbiology*; D006017:Glycolipids / Q000737:chemistry* / Q000378:metabolism; D006020:Glycopeptides / Q000737:chemistry* / Q000378:metabolism; D008264:Macrophages / Q000276:immunology / Q000382:microbiology*; D051379:Mice; D020102:Mycobacterium smegmatis / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D010587:Phagocytosis / Q000276:immunology
chemical_list: D006017:Glycolipids; D006020:Glycopeptides