A psychrotrophic bacterium producing a cold-active β-galactosidase was isolated from Spitsbergen soil and classified as Arthrobacter sp. S3*. The gene encoding β-galactosidase was isolated from the genomic DNA library, sequenced, cloned, expressed in Escherichia coli, purified by ion exchange chromatography and characterized. The Arthrobaster sp. S3* β-galactosidase is a homotrimeric enzyme composed of 74,4 kDa subunits. It is optimally active at pH 6.5-7.5 and 40°C, and exhibits 38-44% of the maximum activity at 5-10°C. This enzyme is activated by Mg2+ and Ca2+ ions, and inhibited by Mn2+, Ni2+ and Co2+ ions. The properties of Arthrobacter sp. S3* β-galactosidase suggests that this enzyme could be useful for low-lactose milk production.
Authors
Additional information
- Category
- Publikacja w czasopiśmie
- Type
- artykuł w czasopiśmie indeksowanym TR Master Journal List
- Language
- angielski
- Publication year
- 2010
