Effects of Basic and Acidic Synthetic Polypeptides on the Adherence of the Oral Bacteria, Streptococcus Mutans and Streptococcus Sanguis, to Hydroxyapatite

摘要

The ability of cariogenic organisms to become attached to tooth enamel is commonly acknowledged to be a first step in the process of dental caries. Attachment of bacterial cells to the teeth has been ascribed, at least in part, to electrostatic effects Rolla (1977) observed that bovine serum albumin and protamine, which respectively bear net negative and positive charges at neutral pH, correspondingly reduce or enhance the attachment of Streptococcus mutans to hydroxyapatite(HA). Rolla attributed his findings to electrostatic interactions of these proteins with negatively-charged bacterial cells. Two basic and two acidic synthetic polypeptides that bind strongly to hydroxyapatite at neutral pH were tested to determine their influence on absorption of two Streptococcus mutans and two Streptococcus sanguis strains to hydroxyapatite. The absorption of the strains was significantly enhanced or reduced by the basic and acidic agents, respectively. Study of acidic polypeptides provided evidence of competition between the polypeptides and the bacterial cells for hydroxyapatite absorption sites.