ADHERENCE OF CANDIDA-ALBICANS TO A CELL-SURFACE POLYSACCHARIDE RECEPTOR ON STREPTOCOCCUS-GORDONII

Candida albicans ATCC 10261 and CA2 bound to cells of the oral bacteri a Streptococcus gordonii, Streptococcus oralis, and Streptococcus sang uis when these bacteria were immobilized onto microtiter plate wells, but they did not bind to cells of Streptococcus mutans or Streptococcu s salivarius, Cell wall polysaccharide was extracted with alkali from S. gordonii NCTC 7869, the streptococcal species to which C, albicans bound with highest affinity, and was effective in blocking the coaggre gation of C. albicans and S. gordonii cells in the fluid phase. When f ixed to microtiter plate wells, the S, gordonii polysaccharide was bou nd by all strains of C. albicans tested, The polysaccharide contained Rha, Glc, GalNAc, GlcNAc, and Gal and was related compositionally to p reviously characterized cell wall polysaccharides from strains of S. o ralis and S. sanguis. The adherence of yeast cells to the immobilized polysaccharide was not inhibitable by a number of saccharides, Antiser um raised to the S. gordonii NCTC 7869 polysaccharide blocked adherenc e of C. albicans ATCC 10261 to the polysaccharide, The results identif y a complex cell wall polysaccharide of S. gordonii as the coaggregati on receptor for C. albicans. Adherent interactions of yeast cells with streptococci and other bacteria may be important for colonization of both hard and soft oral surfaces by C. albicans.