Streptococcus mutans Adherence: Presumptive Evidence for Protein-Mediated Attachment Followed by Glucan-Dependent Cellular Accumulation

Abstract

Adherence of Streptococcus mutans to smooth surfaces has been attributed to the production of sucrose-derived d -glucans. However, several studies indicate that the bacterium will adhere in the absence of sucrose. The present data confirmed that S. mutans adherence to saliva-coated hydroxyapatite beads in the absence of sucrose is described by the Langmuir equation. The nature of the sucrose-independent adherence was studied with the Persea americana agglutinin as a selective adherence inhibitor. Pretreatment of the bacterium with P. americana agglutinin caused a 10-fold reduction in adherence, and the inhibition was not reversed with the addition of sucrose. Pretreatment of S. mutans with proteases also reduced adherence, regardless of the sucrose content, whereas periodate oxidation and glucanohydrolase treatment of the bacteria reduced sucrose-mediated adherence to the levels found for sucrose-independent adherence. The P. americana agglutinin, glucanohydrolase, and pepsin pretreatment of the cells did not eliminate sucrose-induced agglutination. Scanning electron microscopy showed that short streptococcal chains were bound to saliva-coated hydroxyapatite crystals in the sucrose-independent system, whereas the presence of sucrose caused larger bacterial clumps to be found. A two-reaction model of S. mutans adherence was developed from these data. It is proposed that one reaction is attachment to the tooth pellicle which is mediated by cell-surface proteins rather than glucans or teichoic acids. The other reaction is cellular accumulation mediated by sucrose-derived d -glucans and cell surface lectins. A series of sequential adherence experiments with P. americana agglutinin as a selective inhibitor provided presumptive evidence for the validity of our model of S. mutans adherence.

Interaction between surface protein antigens of Streptococcus mutans and human salivary components

“…This observation may be correlated with the ability of basic aminohexoses (and tris), but not the neutral acetylated aminohexoses, to inhibit the binding of Ag I/II to saliva-coated HA. Furthermore, the agglutinin fron-i Persea atnerieatia that inhibits adherence of S. muians to saliva-coated HA is also reported to have affinity for basic proteins (32). Consistent with the known ability of salivary proline-rich proteins to bind to HA (2), the 38,000 and 28,000 bands were among the parotid saliva proteins found to bind to HA.…”

“…However, the evidence suggests that initial colonization in the absence of sucrose is sparse, but permanent colonization, with accumulation of the organism, is greatly enhanced in the presence of sucrose (9,34). Initial adherence, even of low affinity, may be a necessary preliminary to the essentially irreversible adherence that results when glucans are formed by glucosyltransferase activity (32).…”

“…The adherence of 5. tnutans to salivacoated hydroxyapatite (HA) appears to be due to proteins present on the bacterial surfaee, because treatment of the cells with proteases reduces the binding (30,32). Galactosides also diminish adherence (14), but no appropriate lectinlike adhesin has yet been described in this species.…”

Inhibitory Effect ofBacillus velezensison Biofilm Formation byStreptococcus mutans

“…Adhesion of S. mutans occurs by sugar-dependent and sugar-independent mechanisms. Sugar-dependent attachment is mediated by glucan produced from sugars through glucosyltransferases, whereas sugar-independent attachment is mediated by physicochemical forces, such as electrostatic forces, hydrophobic interactions, and hydrogen bonding with the constituents of saliva (24). In this study, the addition of glucose improved the adhesion of S. mutans (Fig.…”

Identification of monoclonal antibody-binding domains within antigen P1 of Streptococcus mutans and cross-reactivity with related surface antigens of oral streptococci

“…These species are distinguished by differences in the guanine and cytosine content of their DNA, sugar fermentation, bacitracin sensitivity, colony morphology on sucrose-containing media, and cell protein profiles obtained by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. All species of mutans streptococci except S. rattus express a high-molecular-weight surface protein which is believed to function as an adhesin enabling the organisms to bind to the salivary pellicle or other plaque microorganisms on tooth surfaces (16,19,29,30,34,41,55). This 185,000-Mr protein was first identified on S. mutans serotype c strains and has been referred to by various investigators as P1 (3,18,28,33,34), antigen B (50,51), I/II (49,62), IF (24), PAc (45,46,57), and MSL-1 (13).…”