Cloning, expression and characterization of a novel cold-adapted β-galactosidase from the deep-sea bacterium Alteromonas sp. ML52

32Citations
Citations of this article
38Readers
Mendeley users who have this article in their library.

Abstract

The bacterium Alteromonas sp. ML52, isolated from deep-sea water, was found to synthesize an intracellular cold-adapted β-galactosidase. A novel β-galactosidase gene from strain ML52, encoding 1058 amino acids residues, was cloned and expressed in Escherichia coli. The enzyme belongs to glycoside hydrolase family 2 and is active as a homotetrameric protein. The recombinant enzyme had maximum activity at 35 °C and pH 8 with a low thermal stability over 30 °C. The enzyme also exhibited a Km of 0.14 mM, a Vmax of 464.7 U/mg and a kcat of 3688.1 S−1 at 35 °C with 2-nitrophenyl-β-D-galactopyranoside as a substrate. Hydrolysis of lactose assay, performed using milk, indicated that over 90% lactose in milk was hydrolyzed after incubation for 5 h at 25 °C or 24 h at 4 °C and 10 °C, respectively. These properties suggest that recombinant Alteromonas sp. ML52 β-galactosidase is a potential biocatalyst for the lactose-reduced dairy industry.

Cite

CITATION STYLE

APA

Sun, J., Yao, C., Wang, W., Zhuang, Z., Liu, J., Dai, F., & Hao, J. (2018). Cloning, expression and characterization of a novel cold-adapted β-galactosidase from the deep-sea bacterium Alteromonas sp. ML52. Marine Drugs, 16(12). https://doi.org/10.3390/md16120469

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free