Isolation of rfb gene clusters directing the synthesis of O polysaccharides consisting of mannose homopolymers and serological analysis of lipopolysaccharides.
Four serotypes of two genera, Escherichia coli O8 and O9 and Klebsiella O3 and O5, produce the O polysaccharides consisting of mannose homopolymers. Previously, we reported the isolation and expression of E. coli O9 rfb in E. coli K-12 strains (Kido et al, J. Bacteriol., 171: 3629-3633, 1989). In this study, R' plasmids carrying his-rfb region of the other three strains were isolated and expressed in E. coli K-12 strain. Serological study of lipopolysaccharides (LPS) synthesized in E. coli K-12 strain was carried out. His-linked rfb genes from E. coli O9 and Klebsiella O3 directed the synthesis of O polysaccharides with the same antigenicity as those of the parental strains in E. coli K-12 strain. On the other hand, rfb genes from E. coli O8 and Klebsiella O5 directed the synthesis of O polysaccharides which were antigenically not identical but partially common to those of the parental strains. A rough strain derived from E. coli O8 synthesized LPS which showed the identical antigenicity as the wild strain when the his-rfb region of E. coli O8 was introduced. The results suggest that some genes located distantly from his are additionally required to complete the synthesis of O polysaccharides of E. coli O8 and Klebsiella O5.
Saeki
A
A
Department of Bacteriology, Nagoya University School of Medicine, Aichi, Japan.
Kido
N
N
Sugiyama
T
T
Ohta
M
M
Iwashita
T
T
Uchiya
K
K
Kato
N
N
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000276:immunology; D005798:Genes, Bacterial; D007709:Klebsiella / Q000145:classification / Q000235:genetics / Q000276:immunology; D008070:Lipopolysaccharides / Q000097:blood* / Q000737:chemistry; D008358:Mannose; D008969:Molecular Sequence Data; D005810:Multigene Family; D019081:O Antigens; D011135:Polysaccharides, Bacterial / Q000737:chemistry / Q000235:genetics*
D008070:Lipopolysaccharides; D019081:O Antigens; D011135:Polysaccharides, Bacterial; D008358:Mannose