Genetic characterization of the Escherichia coli O66 antigen and functional identification of its wzy gene.
Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.
Cheng
Jiansong
J
TEDA School of Biological Sciences and Biotechnology, Nankai University, 23# Hong Da Street, TEDA, Tianjin 300457, P. R. China.
Liu
Bin
B
Bastin
David A
DA
Han
Weiqing
W
Wang
Lei
L
Feng
Lu
L
D004926:Escherichia coli / Q000235:genetics* / Q000276:immunology*; D029968:Escherichia coli Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D016695:Glycosyltransferases / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D019081:O Antigens / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012760:Shigella / Q000235:genetics
D029968:Escherichia coli Proteins; D019081:O Antigens; D016695:Glycosyltransferases; C513753:Wzy polymerase, E coli