L-异亮氨酸菌种选育及发酵条件优化

Breeding of L-Isoleucine Producer and its Optimal Fermentation Conditions

以栖糖蜜棒杆菌（Corynedacterium melassecola）ATCC17965为出发菌株。根据代谢控制发酵原理。经硫酸二乙酯和60^Co诱变处理。定向选育出一株L-异亮氨酸产生菌131-5（SG^r＋LeuME^r＋Leu＋AHV^r＋Suc^g＋Eth^r）。在培养基未经优化的情况下产L-异亮氨酸14-15g／L．同时，考察了培养基及发酵每件对茼株产酸的影响，在优化的培养基和发酵条件下积累L-异亮氨酸19．2g／L．最高时可迭21．3g／L．

Original strain Corynebacterium rnelassecola ATCC17965 was mutated by DES and 60^ Co, then a L-Isoleueine producing strain named 131-5 （SG^r＋ Leu-ME^r ＋ Leu ＋ AHV ＋ Sue^g＋ Eth^r）, was obtained. This strain could produce 14 - 15 g/L of L-Isoleueine. The effects of medium and fermentation conditions on the L-Ile producing strain were also studied. 131-5 could accumulate 19.2g/L of L-Isoleueine averagely and a highest L-Isoleueine level of 21.3g/L could be obtained under the optimal fermentation conditions.