title: Characterization of the recombinant Candida albicans β-1,2-mannosyltransferase that initiates the β-mannosylation of cell wall phosphopeptidomannan.
abstract: The presence of β-mannosides in their cell walls confers specific features on the pathogenic yeasts Candida albicans and Candida glabrata compared with non-pathogenic yeasts. In the present study, we investigated the enzymatic properties of Bmt1 (β-mannosyltransferase 1), a member of the recently identified β-mannosyltransferase family, from C. albicans. A recombinant soluble enzyme lacking the N-terminal region was expressed as a secreted protein from the methylotrophic yeast Pichia pastoris. In parallel, functionalized natural oligosaccharides isolated from Saccharomyces cerevisiae and a C. albicans mutant strain, as well as synthetic α-oligomannosides, were prepared and used as potential acceptor substrates. Bmt1p preferentially utilizes substrates containing linear chains of α-1,2-linked mannotriose or mannotetraose. The recombinant enzyme consecuti-vely transfers two mannosyl units on to these acceptors, leading to the production of α-mannosidase-resistant oligomannosides. NMR experiments further confirmed the presence of a terminal βMan (β-1,2-linked mannose) unit in the first enzyme product. In the future, a better understanding of specific β-1,2-mannosyltransferase molecular requirements will help the design of new potential antifungal drugs.
authors.forename: Emeline
authors.initials: E
authors.lastname: Fabre
authors.forename: Ghenima
authors.initials: G
authors.lastname: Sfihi-Loualia
authors.affiliation: ‡Département de Chimie, École Normale Supérieure, Université Paris 6, UMR CNRS 7203, 75005 Paris, France.
authors.forename: Marilyne
authors.initials: M
authors.lastname: Pourcelot
authors.forename: Bernadette
authors.initials: B
authors.lastname: Coddeville
authors.forename: Frédéric
authors.initials: F
authors.lastname: Krzewinski
authors.forename: Julie
authors.initials: J
authors.lastname: Bouckaert
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Maes
authors.forename: Thomas
authors.initials: T
authors.lastname: Hurtaux
authors.affiliation: †CNRS, UMR 8576, F-59650 Villeneuve d'Ascq, France.
authors.forename: Romaric
authors.initials: R
authors.lastname: Dubois
authors.forename: Chantal
authors.initials: C
authors.lastname: Fradin
authors.affiliation: ‡Département de Chimie, École Normale Supérieure, Université Paris 6, UMR CNRS 7203, 75005 Paris, France.
authors.forename: Jean-Maurice
authors.initials: JM
authors.lastname: Mallet
authors.forename: Daniel
authors.initials: D
authors.lastname: Poulain
authors.forename: Florence
authors.initials: F
authors.lastname: Delplace
authors.forename: Yann
authors.initials: Y
authors.lastname: Guerardel
mesh_terms: D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics; D002473:Cell Wall / Q000201:enzymology*; D008351:Mannans / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008358:Mannose / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008364:Mannosyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010748:Phosphopeptides / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D008351:Mannans; D010748:Phosphopeptides; D011994:Recombinant Proteins; C072108:phosphopeptidomannan; D008364:Mannosyltransferases; C106904:beta-1,2-mannosyltransferase IV; D008358:Mannose