Glycoside hydrolase family 2 exo-β-1,6-galactosidase LpGal2 from Lactobacillus plantarum: Cloning, expression, and enzymatic characterization

Lactobacillus plantarum is a useful microorganism that metabolizes galactose-containing polysaccharides. Genome analysis has shown that L. plantarum contains four β-galactosidase-related genes. Here, we cloned the β-galactosidase gene that encodes the glycoside hydrolase family 2 (GH2) enzyme LpGal2. Recombinant LpGal2 (rLpGal2, 72 kDa) is a homodimer with maximal enzymatic activity at pH 7.0 and 50 °C. Under these conditions, rLpGal2 hydrolyzes...