[A study of lipopolysaccharide derived from Bacteroides gingivalis]

It has been supposed that lipopolysaccharide (LPS) derived from the gram negative bacteria of subgingival plaque is one of the important etiologic factors in periodontal disease. The purpose of this study was to detect specifically the LPS from Bacteroides gingivalis (Bg) and to determine the effects of gram-positive bacteria on LPS in culture supernatant of Bg. Enzyme-linked immunosorbent assay was used for specific detection of LPS from Bg. LPS of Bg could be measured in concentrations as low as 4 micrograms/ml. LPS of Bg was not detected in gingival crevicular fluid from periodontal disease patients. There were no significant differences in the concentration of LPS between the culture supernatant of Bg and co-cultivation of Bg and gram-positive bacteria. In this study, gram-positive bacteria had no effects on release and degradation of LPS in the culture supernatant of Bg.