Beta-galactosidase LacLM (Lactobacillus reuteri) (LacLM)

LacLM beta-galactosidase is a heterodimeric enzyme derived from the probiotic bacterium Lactobacillus reuteri, belonging to the glycosyl hydrolase family 2 (GH2) (Nguyen et al., 2006). It is composed of two subunits, LacL and LacM, which are encoded by overlapping genes and function together to catalyze the hydrolysis of beta-galactosides (Splechtna et al., 2006). The enzyme's primary role is the breakdown of lactose into glucose and galactose, providing a metabolic pathway for the utilization of dairy sugars. Beyond hydrolysis, LacLM is highly valued for its transgalactosylation activity, which facilitates the synthesis of galacto-oligosaccharides (GOS) from lactose (Maischberger et al., 2010). These GOS products act as prebiotics, promoting the growth of beneficial bifidobacteria and lactobacilli in the human gut. In a therapeutic context, LacLM is utilized as an enzyme replacement therapy for individuals with lactose intolerance, helping to alleviate symptoms like bloating and diarrhea. It is also widely used in the food industry to produce lactose-reduced or lactose-free milk products. The enzyme's stability and high yield of prebiotic synthesis make it a significant focus for biotechnological applications in functional food development. Research into LacLM also explores its potential in modulating the gut microbiome to improve overall digestive health. Overall, LacLM represents a versatile biocatalyst with both direct therapeutic benefits and indirect health-promoting properties through prebiotic production.

Other names

Lactobacillus reuteri beta-galactosidaseLacLM heterodimeric beta-galactosidaseGH2 beta-galactosidaseLactaseBeta-D-galactosidase

The enzyme catalyzes the hydrolysis of beta-1,4-glycosidic bonds in lactose and other galactosides through a double-displacement mechanism involving a covalent galactosyl-enzyme intermediate (Nguyen et al., 2006).