ADHERENCE OF GLUCAN-POSITIVE AND GLUCAN-NEGATIVE STRAINS OF STREPTOCOCCUS-BOVIS TO HUMAN EPITHELIAL-CELLS

Adherence to buccal epithelial cells (BEC) and the role played in the binding by lipoteichoic acid (LTA) and other superficial components ha ve been studied in reference and clinical strains of Streptococcus bov is either glucan-positive biotype I or glucan-negative biotype II. To avoid the synthesis of glucan by biotype I strains, adherence was stud ied in bacteria grown in Todd-Hewitt broth, a sucrose deficient medium . Both biotypes were shown to bind to BEC and clinical isolates, irres pective of biotype attached to the same degree but in greater numbers than reference strains. Inhibition studies suggest that at least two m echanisms,-LTA and protein-mediated-are responsible for the adherence of both glucan-positive and negative strains of S. bovis. Moreover, in glucan-positive strains capsular polysaccharides may be also involved .