Glucan-binding protein (Gbp) (GBP)

Streptococcus mutans glucan-binding proteins (GBPs) are a family of non-enzymatic proteins, including GbpA, GbpB, GbpC, and GbpD, that are essential for the formation and structural integrity of dental biofilms [2, 6]. Unlike glucosyltransferases (Gtfs) that synthesize glucans from sucrose, GBPs act as receptors or scaffolding elements that bind to these extracellular polysaccharides, facilitating bacterial adhesion and aggregation on the tooth surface [8, 10]. GbpA and GbpD are secreted proteins that contribute to the three-dimensional architecture of the biofilm, while GbpC is cell-wall anchored and mediates dextran-dependent aggregation [12, 15]. GbpB is unique as it appears to be essential for cell wall maintenance and growth, sharing homology with peptidoglycan hydrolases [9, 11]. These proteins are significant therapeutic targets because their inhibition can prevent the transition of S. mutans into a virulent biofilm state without necessarily killing the bacteria, thereby reducing the risk of dental caries and systemic infections like endocarditis [13, 16]. Experimental strategies targeting GBPs include small-molecule inhibitors like G43, DNA aptamers, and vaccines aimed at inducing protective mucosal immunity [4, 7, 16].

Other names

Glucan-binding protein AGlucan-binding protein BGlucan-binding protein CGlucan-binding protein DGbpAGbpBGbpCGbpDNon-Gtf glucan-binding proteinIDG-60Dextran-binding protein

Inhibition of glucan binding, disruption of biofilm architecture, prevention of bacterial attachment to the tooth surface, and inhibition of cell wall synthesis.