STREPTOCOCCUS-MUTANS MAJOR ADHESION SURFACE PROTEIN, P1 (I II), DOES NOT CONTRIBUTE TO ATTACHMENT TO VALVULAR VEGETATIONS OR TO THE DEVELOPMENT OF ENDOCARDITIS IN A RAT MODEL/

Streptococcus mutans P1 antigen functions as an adhesion factor for bi nding to salivary pellicle on tooth surfaces. It induces increased ant ibody titres in patients with Strep. mutans endocarditis. A mutant of Strep. mutans deficient in the function of the gene (spa P) encoding t he surface antigen P1, and its isogenic parental strain, were used in a rat endocarditis experiment. Absence of P1 did not decrease adhesion to vegetations determined 1 h after intravenous infection. The number of bacteria recovered from valvular vegetations after 48 h from anima ls with manifest endocarditis did not differ between the strains. Cons equently, the P1 antigen appears to be unimportant both for adhesion a nd virulence in endocarditis caused by Strep. mutans. Copyright (C) 19 97 Published by Elsevier Science Ltd.