Binding specificity of Lactobacillus to glycolipids

Lactobacillus, a representative useful bacterium, in the intestinal tract was found to bind to some specific glycosphingolipids, like the pathogenic intestinal bacteria. Thin layer chromatography overlay assays using rabbit antiserum against Lactobacillus casei revealed that the bacteria bound to GA1 and trihexosylceramide strongly, but not to any gangliosides. The bacteria generally bound to glycosphingolipids having short sugar chains and galactosyl moiety in the non-reducing terminal. L.casei did not bind to GM1, but bound to the product after sialidase treatment, GA1. This indicated that sialic acid inhibited the adhesion of L.casei to tissues. L.casei actually bound nonacid glycosphingolipids but not acid glycosphingolipids extracted from the small intestinal mucosa of rats.