Infectivity of a glucan synthesis-defective mutant of Streptococcus gordonii (Challis) in a rat endocarditis model.
Streptococcus gordonii, a member of the human indigenous oral microflora, colonizes smooth tooth surfaces and contributes to dental plaque formation. Although it is not recognized as being a cariogenic pathogen, it may cause endocarditis following invasion of the bloodstream. Using allelic exchange mutagenesis, we have constructed a mutant of S. gordonii (Challis) which is defective in its single functional glucosyltransferase gene and, hence, is unable to synthesize glucan exopolymers from sucrose. When examined in a rat endocarditis model, the sucrose-grown mutant did not differ significantly from S. gordonii wild-type, suggesting that glucan polymers did not contribute to infectivity. This result was in striking contrast to that previously observed with a polymer-defective S. mutans mutant.
Wells
V D
VD
Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond 23298-0678.
Munro
C L
CL
Sulavik
M C
MC
Clewell
D B
DB
Macrina
F L
FL
D000818:Animals; D004195:Disease Models, Animal; D004696:Endocarditis / Q000382:microbiology*; D005936:Glucans / Q000096:biosynthesis*; D005964:Glucosyltransferases / Q000172:deficiency* / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D013291:Streptococcus / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity*; D013395:Sucrose / Q000378:metabolism; D014774:Virulence
D005936:Glucans; D013395:Sucrose; D005964:Glucosyltransferases