Glutamate production from Delta b-glucan using endoglucanase-secreting Corynebacterium glutamicum

We demonstrate glutamate production from Delta *b-glucan using endoglucanase (EG)-expressing Corynebacterium glutamicum. The signal sequence torA derived from Escherichia coli K12, which belongs to the Tat pathway, was suitable for secreting EG of Clostridium thermocellum using C. glutamicum as a host. Using the torA signal sequence, endoglucanase from Clostridium cellulovorans 743B was successfully expressed, and the secreted EG produced 123 mg of reducing sugar from 5 g of Delta *b-glucan at 30 degree C for 72 h, which is the optimal condition for C. glutamicum growth. Subsequently, glutamate fermentation from Delta *b-glucan was carried out with the addition of Aspergillus aculeatus Delta *b-glucosidase produced by recombinant Aspergillus oryzae. Using EG-secreting C. glutamicum, 178 mg/l of glutamate was produced from 15 g of Delta *b-glucan. This is the first report of glutamate fermentation from Delta *b-glucan using endoglucanase-secreting C. glutamicum.