Occurrence of 2-O-methyl-N-(3-deoxy-L-glycero-tetronyl)-D-perosamine (4-amino-4,6-dideoxy-D-manno-pyranose) in lipopolysaccharide from Ogawa but not from Inaba O forms of O1 Vibrio cholerae.

A structural study by GC-MS, methylation analysis, and 1H and 13C NMR was carried out on alpha (1-->2)-linked linear N-(3-deoxy-L-glycero-tetronyl)-D-perosamine homopolymer constituting the O-polysaccharide chain of lipopolysaccharide from O1 Vibrio cholerae Ogawa and Inaba O forms. Occurrence of 2-O-methyl-N-(3-deoxy-L-glycero-tetronyl)-D-perosamine was demonstrated at the non-reducing terminus of the perosamine-homopolymer of lipopolysaccharide from the Ogawa O form in contrast to the presence of N-(3-deoxy-L-glycero-tetronyl)-D-perosamine at the nonreducing terminus for the Inaba O form.