Role of the rfe gene in the biosynthesis of the Escherichia coli O7-specific lipopolysaccharide and other O-specific polysaccharides containing N-acetylglucosamine.
We report that rfe mutants of wild-type strains of Escherichia coli O7, O18, O75, and O111 did not express O-specific polysaccharide unless the rfe mutation was complemented by a cloned rfe gene supplied in a plasmid. The O polysaccharides in these strains are known to have N-acetylglucosamine (GlcNAc) in their O repeats. In addition, in vitro transferase assays with bacterial membranes from either the O7 wild-type strain or its isogenic rfe mutant showed that GlcNAc is the first carbohydrate added onto the lipid acceptor in the assembly of the O7 repeat and that this function is inhibited by tunicamycin. Our results indicate that the rfe gene product is a general requirement for the synthesis of O polysaccharides containing GlcNAc.
Alexander
D C
DC
Department of Microbiology and Immunology, University of Western Ontario, London, Canada.
Valvano
M A
MA
D000117:Acetylglucosamine; D000371:Agglutination; D015153:Blotting, Western; D002240:Carbohydrate Sequence; D004755:Enterobacteriaceae / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D008070:Lipopolysaccharides / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D009154:Mutation; D019081:O Antigens; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000235:genetics; D013729:Terpenes / Q000378:metabolism; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics* / Q000378:metabolism; D014531:Uridine Diphosphate Galactose / Q000378:metabolism; D014537:Uridine Diphosphate N-Acetylglucosamine / Q000378:metabolism
D029968:Escherichia coli Proteins; D008070:Lipopolysaccharides; D019081:O Antigens; D011135:Polysaccharides, Bacterial; D013729:Terpenes; D014531:Uridine Diphosphate Galactose; D014537:Uridine Diphosphate N-Acetylglucosamine; D017855:Transferases (Other Substituted Phosphate Groups); C083617:wecA protein, E coli; C043081:decaprenoic acid; D000117:Acetylglucosamine