Transport of N-acetyl-D-mannosamine and N-acetyl-D-glucosamine in Escherichia coli K1: effect on capsular polysialic acid production.
N-Acetyl-D-mannosamine (ManNAc) and N-acetyl-D-glucosamine (GlcNAc) are the essential precursors of N-acetylneuraminic acid (NeuAc), the specific monomer of polysialic acid (PA), a bacterial pathogenic determinant. Escherichia coli K1 uses both amino sugars as carbon sources and uptake takes place through the mannose phosphotransferase system transporter, a phosphoenolpyruvate-dependent phosphotransferase system that shows a broad range of specificity. Glucose, mannose, fructose, and glucosamine strongly inhibited the transport of these amino-acetylated sugars and GlcNAc and ManNAc strongly affected ManNAc and GlcNAc uptake, respectively. The ManNAc and the GlcNAc phosphorylation that occurs during uptake affected NeuAc synthesis in vitro. These findings account for the low in vivo PA production observed when E. coli K1 uses ManNAc or GlcNAc as a carbon source for growth.
Revilla-Nuin
Beatriz
B
Departamento de Bioquímica y Biología Molecular, Universidad de León, Campus de Vegazana, 24007 León, Spain.
Reglero
Angel
A
Martínez-Blanco
Honorina
H
Bravo
Ignacio G
IG
Ferrero
Miguel A
MA
Rodríguez-Aparicio
Leandro B
LB
D000117:Acetylglucosamine / Q000378:metabolism*; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D002455:Cell Division; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism*; D006595:Hexosamines / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010770:Phosphotransferases / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis; D012794:Sialic Acids / Q000096:biosynthesis*; D013696:Temperature; D013997:Time Factors
D006595:Hexosamines; D011135:Polysaccharides, Bacterial; D012794:Sialic Acids; C021319:polysialic acid; D010770:Phosphotransferases; D000117:Acetylglucosamine; C002022:N-acetylmannosamine