The heterocyclic amine binding receptors of Lactobacillus gasseri cells.

Lactobacillus gasseri is a common inhabitant of human intestine. The L. gasseri strains SBT10239 and SBT10241 have shown high antimutagenicity and binding properties with different heterocyclic amines. In order to identify the cell wall components involved in binding with the heterocyclic amines, the cells and cell walls of L. gasseri strains were subjected to different chemical and enzymatical treatments, prior to the binding experiments. The results indicated that the binding receptors for heterocyclic amines are the carbohydrate moieties of the cell wall. Binding of the heterocyclic amines with L. gasseri cell walls and the carbohydrate content showed high correlation coefficient, whereas it was insignificant or negative with protein content. The lectin binding studies revealed that the glucose molecules of the cell wall has a significant role in binding the heterocyclic amines. The inhibition caused by the lectin Concanavalin A was reversed when treated with methyl glucoside, a competitive inhibitor of Concanavalin A and restored the binding of heterocyclic amine with the cells.