Mutan (alpha-1,3-glucan)

Mutan is a water-insoluble polysaccharide primarily composed of alpha-1,3-linked glucose residues, synthesized by Streptococcus mutans and other oral streptococci via glucosyltransferase (Gtf) enzymes [2, 5]. It serves as a fundamental structural component of the extracellular polymeric substance (EPS) matrix in dental plaque, facilitating the stable adherence of cariogenic bacteria to tooth surfaces and mediating inter-bacterial aggregation [8, 11]. By providing a protective and cohesive scaffold, mutan promotes the development of biofilms that trap organic acids produced during sugar fermentation, which eventually leads to the demineralization of tooth enamel and the formation of dental caries [3, 9]. Beyond its structural role, mutan has been shown to induce inflammatory responses by stimulating osteoclast differentiation, potentially contributing to alveolar bone loss in periodontal disease [21]. In therapeutic contexts, mutan is considered a key target for anti-biofilm strategies, where enzymes such as mutanase (alpha-1,3-glucanase) are utilized to hydrolyze its glycosidic bonds, thereby destabilizing the plaque matrix and enhancing the efficacy of mechanical cleaning and antimicrobial agents [7, 14].

Other names

alpha-1,3-linked glucanWater-insoluble glucanInsoluble streptococcal glucanMutan polysaccharide

Enzymatic hydrolysis of alpha-1,3-glycosidic linkages to degrade the dental biofilm matrix, or inhibition of its synthesis to prevent bacterial colonization [9, 14].