Adhesive cell wall-associated glycoprotein of Streptococcus salivarius (K⁺) is a cell surface fibril

Abstract

The structure of a cell wall-associated glycoprotein, supposed to be involved in host-related adherence of Streptococcus salivarius (K⁺) strains, was investigated. The M_r of the two major subclasses of the glycoprotein was estimated to be in the range of 230 000 to 295 000, both in the presence of SDS and under non-denaturating conditions. Circular dichroism spectra indicated an α-helix content of 45%. Electron microscopic observation of rotary shadowed individual molecules showed fibrillar structures with an average length of 870 ± 40 Å and a width of 75 ± 6 Å. The glycoprotein is presumably identical with a class of long fibrils found on the surface of these cells.

Cell surface morphology, adhesion, oral microflora