Description
General description
β-Galactosidase is a member of the glycoside hydrolase clan A (GH-A) family. It is widely present in microorganisms, which includes both prokaryotes and eukaryotes.
Application
β-Galactosidase from Aspergillus oryzae has been used:
in in vitro nuclear magnet resonance (NMR)
as a standard in the β-galactosidase assay to determine the concentration of cell-associated β-galactosidase
to modify sugar residues on the surface of the mutant slime cells to study the adhesive properties
for enzymatic hydrolysis of lactose
for reversed-phase (RP) adsorption
in the hydrolysis of whey lactose
Biochem/physiol Actions
β-Galactosidase acts on the terminal β-D-galactosyl moieties of disaccharides, glycoconjugates, and polysaccharides. It is useful in mediating transglycosylation reactions such as the synthesis of galactooligosaccharides (GOS). β-Galactosidases might be used for glycobiological and biotechnological applications.
β-galactosidase cleaves lactose into its monosaccharide components, glucose and galactose. It also catalyses the transglycosylation of glucose into allolactose, the inducer of β-galactosidase, in a feedback loop.
Other Notes
One unit will hydrolyze 1.0 μmole of lactose per minute at pH at 4.5 at 30 °C.