Bifidobacterium breve 203, an isolate which assimilates β -D-glucosides weakly, came to grow well on cellobiose (B. breve clb strain) or gentiobiose (B. breve gnt strain) after successive transfers in medium containing cellobiose or gentiobiose as a carbon source. The elevation of the assimilating ability of B. breve clb, which might reflect both higher cellobiose consuming- and β -D-glucosidase I activities than those of the original B. breve 203, was specific to cellobiose. In the case of B. breve gnt, the elevated assimilating ability was specific to gentiobiose, with higher gentiobiose consuming- and β -D-glucosidase II activities. Subsequent transfers (10 times) of B. breve clb in medium with glucose as a carbon source resulted only in a decrease in cellobiose consumption by the intact cells, while similar treatment of B. breve gnt resulted in decreases in both gentiobiose consumption and β - D-glucosidase II activity. β -D-Glucosidase I partially purified from B. breve clb grown on glucose as a carbon source showed the same properties as the enzyme from B. breve 203 in molecular weight, optimum pH for the reaction, effects of divalent cations and sulfhydryl reagents, substrate specificity, β -D-fucoside-transferring activity and so on.
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Agricultural and Biological Sciences(all)