Cell surface mutants of Streptococcus sanguis with altered adherence properties

Abstract

Two mutants of Streptococcus sanguis (Challis) with altered cell‐surface hydrophobicities were isolated after mutagenesis with ethyl methanesulphonate. Cells of one mutant were more hydrophobic than those of the parent strain and they adhered better to hexadecane, octyl‐Sepharose, hydroxylapatite, saliva‐treated hydaroxylapatite, and to Actinomyces viscosus. The second mutant had reduced hydrophobicity, and cells adhered less well to all the above surfaces except the actinomycetes, adsorption to which was similar to that of the wild‐type strain. The differences in hydrophobicity of the mutants were associated with alterations in amount and exposure of surface proteins, in particular two envelope proteins (Mr 43,000 and 45,000). The properties of the mutants support the contention that hydrophobic forces are determinants in S. sanguis adherence.

Gene disruption identifies a 290 kDa cell‐surface polypeptide conferring hydrophobicity and coaggregation properties in Streptococcus gordonii

“…Cell surface proteins of streptococci are currently receiving much interest both in relation to bacterial colonization and virulence, and as candidates for the development of effective vaccines against streptococcai infections. In this study, antiserum directed to a 43 kDa surface-exposed protein of S. gordonii DL1-Challis, that was previously implicated in hydrophobicity and coaggregation reactions (Jenkinson and Carter, 1988), was used to screen an expression library of S. gordonii DNA. A gene fragment was cloned that turned out unexpectedly to encode the Cterminus of a much larger 290 kDa polypeptide.…”

“…Mutants with either reduced or increased cell-surface hydrophobicity were isolated following ethylmethane sulphonate mutagenesis of S. gordonii (Jenkinson and Carter, 1988). A mutant with increased surtace hydrophobicity, designated strain OB74, coaggregated better with oral actinomyces (Jenkinson and Carter, 1988) and this was associated with alterations in the amount and exposure of two streptococcal cell-surtace proteins of 43 and 45 kDa (Jenkinson and Carter, 1988). The results in this paper describe the identification of a kOa 218-I 2 3 4 5…”

“…Several cell surface proteins have been implicated in adherence, hydrophobicity and aggregation reactions in S, gordonii (Jenkinson, 1986;1987;Jenkinson and Easingwood, 1990). Mutants with either reduced or increased cell-surface hydrophobicity were isolated following ethylmethane sulphonate mutagenesis of S. gordonii (Jenkinson and Carter, 1988). A mutant with increased surtace hydrophobicity, designated strain OB74, coaggregated better with oral actinomyces (Jenkinson and Carter, 1988) and this was associated with alterations in the amount and exposure of two streptococcal cell-surtace proteins of 43 and 45 kDa (Jenkinson and Carter, 1988).…”

Expression of the Surface Properties of the Fibrillar Streptococcus salivarius HB and Its Adhesion Deficient Mutants Grown in Continuous Culture under Glucose Limitation

“…Protein bands at 43 and 45 kDa have recently been suggested to be involved with adhesion and surface hydrophobicity in S . sanguis Challis (Jenkinson & Carter, 1988). The cell surface proteins from S .…”

Saliva-Bacterium Interactions in Oral Microbial Ecology

“…Surface hydrophobicity has also been associated with the presence of fimbriae Handley and Tipler, 1986). A mutant of S. sanguis with increased surface hydrophobicity adhered better to saliva-coated hydroxyapatite, while a mutant with lower hydrophobicity adhered less well to saliva-coated hydroxyapatite (Jenkinson and Carter, 1988). Also, the nonpolar compound p-dioxane was found to enhance the rate and extent of bacterial adhesion, suggesting a role for hydrophobic interactions in this process (Olsson et al, 1990).…”