E.coli ATCC 21990 변이주의 유가배양법에 의한 Aminoglycoside-3'-Phosphotransferase 생산

Production of Aminoglycoside-3'-Phosphotransferase by the Fed-Batch Cultivation of Mutant Obtained from E. coli ATCC 21990

Aminoglycoside-3'-phosphotransferase(APH(3'))를 생산하는 균주인 E.coli ATCC 21990을 산업적으로 이용하기 위해서 자외선 조사 및 NTG를 처리하고 고농도의 kanamycin B에 내성을 갖는 변이주인 E.coli M1과 M2를 선별하였다. E.coli M1은 단위 균체당 효소 생산성은 높으나 생육속도가 낮아 실용적이질 못했고 주 질소원인 yeast extract를 사용했을때 E.coli M1보다 E.coli M2가 생육속도가 훨씬 빨랐으며 약 2배의 APH(3')을 얻을 수 있었고 산소 가스를 사용하였을 경우는 약 2.5배의 APH(3')을 얻었다.

To maximize the production of aminoglycoside-3'-phosphotransferase of E. coli ATCC 21990 carrying R factor which encodes aminoglycoside-3'-phosphotransferase (APH(3')) phosphorylating the 3'-hydroxyl group of aminoglycoside, mutants M1 and M2, media composition and several factors affecting the enzyme production during fermentation were studied. Although the specific activity of APH(3') produced by a mutant M1 was increased as much as four times than that of E. coii ATCC 21990, the growth rate was decreased. The increase of the enzyme production was obtained by increased biomass during fermentation. A mutant M2 was obtained to increase the cell growth rate. Mutant M2 cells were cultivated with optimal media and pure oxygen gas in a fed-batch mode of fermentor operation. The specific activity of APH(3') was decreased, but total enzyme activity of APH(3') was increased as much as two point five times than that of mutant MI.