Growth in the presence of sucrose may decrease attachment of some oral bacteria to abiotic surfaces

Synthesis of cell-bound glucan from dietary sucrose by oral pathogenic bacteria may influence bacterial cell surface properties and colonization of surfaces. This study investigated the effects of the addition of 2 % sucrose to culture medium on cell surface properties (hydrophobicity, charge, and auto-aggregation) and colonization activities (attachment and biofilm formation) on three abiotic surfaces (hydroxyapatite, glass, and stainless steel) of two Streptococcus mutans strains, one Streptococcus salivarius strain, one Streptococcus mitis strain, and one Actinomyces naeslundii strain. The results showed that the additional sucrose reduced the hydrophobicity of three strains (44-62 %) and increased that of one strain (31 %). Cellular aggregation of one strain was decreased (13 %) and that of another increased (21 %). No change in the surface charge of strains was apparent. Additional sucrose also inhibited the attachment of three strains (0.6-1.3 log CFU cm−2) and enhanced that of one strain (0.5-1.3 log CFU cm−2) to glass and stainless steel. The attachment of two strains to hydroxyapatite was reduced (0.9-1.3 log CFU cm−2). Biofilm formation by four strains was enhanced on all surfaces (0.4-1 log CFU cm−2). No relationship between changes in cell surface properties and changes in colonization activities was apparent. Sucrose does not always enhance oral bacterial colonization of abiotic surfaces