CLONING OF GENE FOR BETA-GLUCOSIDASE FROM RUMINOCOCCUS-ALBUS-7

A gene coding for beta-glucosidase from the rumen bacteria, Ruminococc us albus 7, was cloned into Escherichia call DHS alpha by using plasmi d pUC19, A R albus 7 genomic library was prepared in E. coli by using partially Sau3AI-digested DNA. Transformants were screened for beta-gl ucosidase activity on the basis of formation of blue colonies on LB ag ar plates containing 5-bromo-4-chloro-3-indolyl-beta-D-glucoside. A cl one containing beta-glucosidase activity was found and its recombinant DNA structure was found to contain a 3.1 kilobase insert, beta-Glucos idase activity against p-nitrophenyl-beta-D-glucoside (PNPG) expressed by the E. coli clone was found to be 42 times greater than that expre ssed by the original R albus 7.