Saliva-Bacterium Interactions in Oral Microbial Ecology

Abstract

Saliva is thought to have a significant impact on the colonization of microorganisms in the oral cavity. Salivary components may participate in this process by one of four general mechanisms: binding to microorganisms to facilitate their clearance from the oral cavity, serving as receptors in oral pellicles for microbial adhesion to host surfaces, inhibiting microbial growth or mediating microbial killing, and serving as microbial nutritional substrates. This article reviews information pertinent to the molecular interaction of salivary components with bacteria (primarily the oral streptococci and Actinomyces) and explores the implications of these interactions for oral bacterial colonization and dental plaque formation. Knowledge of the molecular mechanisms controlling bacterial colonization of the oral cavity may suggest methods to prevent not only dental plaque formation but also serious medical infections that may follow microbial colonization of the oral cavity.

Cross-feeding and interkingdom communication in dual-species biofilms of Streptococcus mutans and Candida albicans

“…The microtitre plates (Thermo Fisher Scientific, Rochester, NY, USA) used for biofilm formation were coated with artificial saliva for 1 h at 37 1C to mimick the conditions in the oral cavity (Wong and Sissons, 2001). Natural saliva has a crucial role for the colonization of dental enamel (Scannapieco, 1994). Following the removal of artificial saliva, the inoculum was pipetted into the coated well (1 ml for 24-well microtitre plates and 0.2 ml for 96-well microtitre plates).…”

Differential metabolic activity by dental plaque bacteria in association with two preparations of MUC5B mucins in solution and in biofilms

“…In the latter process, salivary mucins contribute substantially to the formation of the acquired pellicle, or conditioning film, in the oral cavity (Nieuw Amerongen et al, 1989;Tabak, 1995) and can influence the establishment and selection of the oral microflora by promoting the adhesion of certain bacteria and facilitating the clearance of other species (e.g. Marsh, 2003;Scannapieco, 1994). The attached bacteria then grow and modify the local environment, making the site suitable for the colonization of more fastidious species.…”

Local and Systemic Up-regulation of TNFα, IL-1β and IL-6 in Mice Intratracheally Inoculated with Porphyromonas gingivalis

“…Many other bacteria that can induce lung inflammation are also present in the oral cavity (Scannapieco 1994;russell et al 1999). Gingival fluid and saliva flow constantly rinse out bacteria from the dental plaque, so the aspiration of saliva is a possible cause of recurring lung inflammation leading to irreversible tissue damage (Scannapieco 1994;2005). Additionally, enzymes released from diseased periodontal tissues influence bacterial colonization of the respiratory epithelium by decomposing salivary and airway mucin, which normally traps bacteria and prevents their binding to respiratory epithelium (Scannapieco and Genco 1999).…”

“…When periodontal disease is established, periodontopathogenic bacteria such as P. gingivalis are numerous. Many other bacteria that can induce lung inflammation are also present in the oral cavity (Scannapieco 1994;russell et al 1999). Gingival fluid and saliva flow constantly rinse out bacteria from the dental plaque, so the aspiration of saliva is a possible cause of recurring lung inflammation leading to irreversible tissue damage (Scannapieco 1994;2005).…”