Production of recombinant alpha-galactosidases in Thermus thermophilus.

ABSTRACT: A Thermus thermophilus selector strain for production of thermostable and thermoactive alpha-galactosidase was constructed. For this purpose, the native alpha-galactosidase gene (agaT) of T. thermophilus TH125 was inactivated to prevent background activity. In our first attempt, insertional mutagenesis of agaT by using a cassette carrying a kanamycin resistance gene led to bacterial inability to utilize melibiose (alpha-galactoside) and galactose as sole carbohydrate sources due to a polar effect of the insertional inactivation. A Gal(+) phenotype was assumed to be essential for growth on melibiose. In a Gal(-) background, accumulation of galactose or its metabolite derivatives produced from melibiose hydrolysis could interfere with the growth of the host strain harboring recombinant alpha

SUBMITTER: Fridjonsson O 

PROVIDER: S-EPMC93147 | biostudies-literature | 2001 Sep

REPOSITORIES: biostudies-literature