Overproduction f Pseudomonas sp. LBC505 Endoglucanase in Escherichia coli and Bacillus Subtilis

다국어 초록 (Multilingual Abstract)

Endoglucanase gene of Pseudomonas sp. LBC505 was previously cloned in pUC19 to yield plasmid pLC1. overproduction of endoglucanase was attempted by following ways. First, the endoglucanase gene of Pseudomonas sp. LBC505 cloned in pUC19(pLC1) was tandemly inserted, step by step, into a expression vector pKK223-3 in a directly repeated form to enhance productivity of endoglucanase. Escherichia coli containing pKCC30 among the resulting plasmids showed the higher yield of the endoglucanase. E.coli harboring pKCC30 which had three inserted endoglucanase genes expressed about 12.3 times as much CMCase activity as E.coli harboring pLC1. Second, the endoglucanase gene was subcloned into Bacillus subtilis expression vector pgnt41 for both overproduction and extracellular secretion of the endoglucanase. A resulting plasmid pgntc15 in Bacillus subtilis expressed 4.3-fold higher levels of CMCase activity than that of E.coli harboring pLC1 and the endoglucanase produced was entirely secreted into the culture medium.