A comparative study of the sugar composition of O-antigenic lipopolysaccharides isolated from Vibrio alginolyticus and Vibrio parahaemolyticus.

A comparative study of the sugar composition of O-antigenic lipopolysaccharides (LPS) isolated from Vibrio alginolyticus and those from V. parahaemolyticus was carried out. 3-Deoxy-D-mannooctulosonic acid, 2-keto-3-deoxy octonate (KDO), a regular sugar constituent of gram-negative bacterial LPS, was totally absent from LPS of all V. alginolyticus strains examined as it was from those of V. parahaemolyticus. Furthermore, a KDO-like thiobarbituric acid test-positive substance, identical with that of either V. parahaemolyticus 07 or 012, was also found in LPS from three strains, 505-78, 905-78, and 1013-79 (designated tentatively as group I), out of the five strains of V. alginolyticus tested. LPS from the members of group I contained, as component sugars, glucose, galactose, L-glycero-D-manno-heptose, glucosamine, galactosamine, the KDO-like substance, and an unidentified amino sugar P1. Thus, LPS of the members of group I possessed a similar sugar composition which is similar to that of LPS from either V. parahaemolyticus 97 or 012. LPS of strain 1027-79, one of the other two strains (designated tentatively as group II), contained as component sugars, glucose, L-glycero-D-mannoheptose, glucosamine, galactosamine, galactosamine, and the other unidentified amino sugar P2, while LPS of strain 53-79, the other member of group II, contained galactose as an additional component. The results indicate that LPS of strain 1027-79 has a sugar composition similar to that of V. parahaemolyticus 09 LPS.