Dextran Production as a Possible Virulence Factor in Streptococcal Endocarditis 1

Summary

The hypothesis that dextran production from sucrose by Streptococcus sanguis contributes to the infectivity of this organism in the development of bacterial endocarditis was tested in a rabbit model of experimental endocarditis using a dextran producing strain and an ultraviolet induced dextran-negative mutant. Sucrose grown dextran producing organisms were more infective than organisms grown in broth solutions without sucrose, whereas sucrose did not increase the infectivity of the dextran negative mutant. Dextran production appears to be a virulence factor in the production of streptococcal endocarditis.