LacLM beta-galactosidase (Lactobacillus reuteri) (LacLM)

LacLM beta-galactosidase is a heterodimeric enzyme produced by the probiotic bacterium Lactobacillus reuteri, belonging to the glycoside hydrolase family 2 (GH2) (Nguyen et al., 2006). The enzyme is composed of two subunits, LacL and LacM, which are encoded by overlapping genes and must associate to form a functional catalytic unit (Splechtna et al., 2006). Its primary biological function is the hydrolysis of lactose into the monosaccharides glucose and galactose, providing a mechanism to alleviate symptoms of lactose intolerance (UniProt P0C1U8). Additionally, LacLM is notable for its high transgalactosylation activity, which facilitates the synthesis of galacto-oligosaccharides (GOS) from lactose (Maischberger et al., 2010). These GOS function as prebiotics, promoting the growth of beneficial gut bacteria and supporting overall intestinal health. In a therapeutic context, the enzyme is utilized in enzyme replacement therapies and probiotic supplements to improve dairy digestion and modulate the gut microbiome (Iqbal et al., 2010).

Other names

Beta-galactosidaseLactaseLacL/LacM heterodimeric beta-galactosidaseGlycoside hydrolase family 2 beta-galactosidase

Hydrolysis of the beta-1,4-glycosidic bond in lactose via a double-displacement mechanism and synthesis of galacto-oligosaccharides through transgalactosylation (Nguyen et al., 2006).