Schumacher, U.K. *, Maennel, M., and Werner, H.,
Dept. Med. Microbiol., Eberhard-Karls-University, D-72076 Tübingen, Germany

Phospholipids and glycolipids have been shown to function as receptors for several respiratory tract pathogens. The adherence of 96 strains be-longing to eigth Bacteroides species as well as of 10 Bilophila wadsworthia isolates to four phospho-lipids and 12 glycolipids was determined using a microtiter plate assay. In comparison with the values of a Helicobacter pylori strain (DSM 4867), the results obtained were interpreted as positive when attaining 90% of the H.pylori values.

Binding to phosphatidylcholine (PC) and globo-triaosylceramide (Glo3) respectively was found in 36.5% and 35.4% of the strains as well as for asialoganglioside-gm2 (Gg3), asialoganglioside-gm1 (Gg4) and phophatidylethanolamine (PE) respectively in 28.1%, 14.6% and 12.5%. Adhesion to PC was found in all Bacteroides species, whereas binding to PE was only found in four Bacteroides species. Adhesion to Gg3, Gg4 and Glo3 was more frequently present in B.vulgatus and B.thetaiotaomicron strains than in B.fragilis isolates. Statistically significant differences were found in adhesion of B.vulgatus strains and B.fragilis isolates to Gg4 and Glo3 (p<0.05). Further testing of one B.caccae strain showed that preincubation with bismut salts inhibited adhesion to PC, PE, Gg3 and Gg4. Binding of three other tested strains to PC, Gg3 and Gg4 were reduced by protease treatment. Adhesion was not influenced by carbohydrates or pretreatment of bacterial cells with trypsin or periodate. None of the B.wadsworthia strains was found adhesive to any of the tested lipid compounds.

Phospholipid and glycolipid adhesive properties were found in intestinal Bacteroides species, predominantly in B.vulgatus, suggesting that lipid adhesion may play a role in establishing intestinal flora.