13 by: Hannah Mault

Student – Hannah Mault

Enzyme: Beta-galactosidase

E.C #: 3.2.1.23

Beta-galactosidase in a hydrolysis enzyme found in bacteria, yeast, fungi, plants, and animals. Beta galactosidase is a hydrolase enzyme that can be found in many different organisms.
Its main function is to hydrolyze lactose into glucose and galactose. It contains 2 important amino acid residues (glu537 and glu461) that mainly interact with the substrate during hydrolysis. For optimal function, it requires the presence of magnesium and sodium/potassium cofactors to help with binding and reactivity. Beta-galactosidase is specific to beta-galactoside substrates (galactose sugars containing a beta-glycosidic bond). A reduction in the function of beta-galactosidase is the main cause of lactose intolerance in humans.

References
1. Joaquin, T. Lactase Enzyme Biochemistry. YouTube, 2021. https://www.youtube.com/watch?v=LjkXYJe6SFU&t=38s
2. Juers D. H.; Huber, R.E.; Matthews, B.W. LacZ β-galactosidase: structure and function of an enzyme of historical and molecular biological importance. Protein Science: a Publication of the Protein Society. 2012, 21 (12), 1792-1807. https://europepmc.org/article/ MED/23011886
3. Kalathinathan, P.,Muthukaliannan, G. K.;Pulicherla, K.; Sain, A. A Review on the Various Sources of β-Galactosidase and its Lactose Hydrolysis Property. Curr Microbiol, 2023, 80, 122. https://doi.org/10.1007/ s00284-023-03220-4