Two different O-polysaccharides from Escherichia coli O86 are produced by different polymerization of the same O-repeating unit.
The structure of a new O-polysaccharide from Escherichia coli O86:K62:B7 was determined using NMR and methylation analysis. The structure is as follows: [carbohydrate: see text]. Comparison with the previously published structure from E. coli O86:K2:H2 revealed that the O-polysaccharides from these two E. coli O86 serotypes share the same branched pentasaccharide repeating unit. However, they differ in the anomeric configuration of the linkage, the linkage position, and the identity of the residue through which polymerization occurs. The immunochemical activity of these two forms of LPS toward anti-B antibody was studied and compared. The results showed that LPS from E. coli O86:K2:H2 strain possesses higher blood group B reactivity. The immunoreactivity difference was explained by modeling of the O-repeating unit tetrasaccharide fragments. This finding provides a good system for the further study of O-polysaccharide biosynthesis especially the repeating unit polymerization mechanism.
Yi
Wen
W
Department of Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
Bystricky
Peter
P
Yao
Qingjia
Q
Guo
Hongjie
H
Zhu
Lizhi
L
Li
Hanfen
H
Shen
Jie
J
Li
Mei
M
Ganguly
Soumya
S
Bush
C Allen
CA
Wang
Peng G
PG
D000017:ABO Blood-Group System / Q000276:immunology; D000937:Antigen-Antibody Reactions; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004926:Escherichia coli / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007536:Isomerism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D019081:O Antigens / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification
D000017:ABO Blood-Group System; D019081:O Antigens