Adsorbed Salivary Acidic Proline-rich Proteins Contribute to the Adhesion of Streptococcus mutans JBP to Apatitic Surfaces

Abstract

Experimental pellicles formed on hydroxyapatite (HA) beads from parotid or submandibular saliva promoted the adhesion of Streptococcus mutans JBP cells to a greater extent than did pellicles prepared from buffer, human plasma, or serum. The nature of the salivary components responsible was studied by the preparation of pellicles from fractions of parotid saliva obtained by chromatography on Trisacryl GF 2000 columns. Two groups of fractions promoted attachment of the organism. Components migrating in the high-molecular-weight mucin fraction were most effective, but a later-eluting fraction also possessed adhesion-promoting activity. Subfractionation of the latter material indicated that the adhesion-promoting activity was associated with the acidic proline-rich proteins (PRPs). Pellicles prepared from 10-20-micrograms/mL solutions of pure PRP-1 were effective in promoting attachment of S. mutans JBP cells. PRP-3 was less effective, while human salivary statherin, fibrinogen, fibronectin, type 1 collagen, and the amino-terminal tryptic peptide derived from PRP-1 were ineffective. The quantities of 150-residue and 106-residue PRPs and of statherin, which became incorporated into experimental pellicles prepared from saliva, were estimated with use of radiolabeled protein tracers. The data obtained suggest that these proteins compete for similar binding sites on HA, and that their ratios in saliva would therefore influence the quantity of the larger PRPs that become incorporated into the pellicle. Such competition may contribute to the variability observed in the adhesion-promoting activities of different saliva samples.

Human Salivary Acidic Proline-Rich Proteins (APRP-1/2) In Adult Patients With Dental Caries

“…The N-terminal domain ensures coupling of APRP-1/2 to hydroxyapatite and formation of the acquired enamel pellicle. In parallel the C-terminal domain of APRP-1/2 binds to oral bacteria, promoting bacterial colonization of dental surface, which may play a significant role in pathogenesis of caries [9,20].…”

Inhibition of adhesion of Streptococcus mutans to hydroxylapatite by commercial dairy powders and individual milk proteins

“…Also, logistical problems are often associated with saliva collection as it is difficult if not impossible to collect all samples and perform assays on the same day. Freezing can have an undesirable influence on saliva, as adherence of S. mutans can vary between different samples from an individual after freezing [30]. In addition, precautions associated with the handling of bodily fluids are not required if PBS-HA is employed, and the adherence assay is more sensitive as there is little variation associated with using a buffer of which the exact composition is known.…”

Biological and molecular characterization of Streptococcus crista strains isolated from human dental biofilm by means of arbitrary primers - PCR (AP-PCR)

“…Therefore, because salivary amylase and mouth cells are components of the acquired pellicle, it could be suggested that adherence and amylase-binding are mechanisms used by S. crista for biofilm formation. As shown in other works (11,39,47), the biofilm helps cell-cell communication, which is important in the formation and development of the oral bacterial community composed by S. crista and other oral pathogens, as suggested by Xie et al (46). However, the exact role of S. crista has not been fully elucidated yet.…”