Identification Of N-3-Hydroxypropionyl-2-O-Methyl-D-Perosamine As A Specific Constituent Of The Lipopolysaccharide From Vibrio Bio-Serogroup 1875 Which Has Ogawa Antigen Factor B Of Vibrio Cholerae O1

A marine vibrio, designated Vibrio bio-serogroup 1875 Original (1875 Original), has both the Ogawa antigen factor B and the Inaba antigen factor C of Vibrio cholerae O1, in addition to its own O antigen factor. Its variant strain (1875 Variant) has the Inaba antigen factor C. The O polysaccharide chain (O-chain) of the lipopolysaccharide (LPS) isolated from this vibrio has been shown to consist of an --> (1 2)-linked homopolymer of N-3-hydroxypropionyl-D-perosamine. The present structural study revealed the presence of N-3-hydroxypropionyl-2-O-methyl-D-perosamine at the non-reducing terminus of the O-chain from the LPS of 1875 Original but not from that of the 1875 Variant. Since 2-O-methyl-D-perosamine is known as an Ogawa-specific constituent of the O-chain from V. cholerae O1 Ogawa O form, it appears that the presence of 2-O-methyl-D-perosamine at the non-reducing terminus of the --> (1 2)-linked D-perosamine homopolymer that forms the O-chain is responsible for the expression of the serological specificity of the Ogawa antigen factor B of 1875 Original.