基因工程菌A_(56)(pPA_(22))生物合成青霉素酰化酶的发酵工艺研究

STUDIES ON THE BIOSYNTHETIC TECHNOLOGY OF PENICILLIN ACYLASE OF E.OOLI A_(56)(pPA_(22)) GENE

青霉素酰化酶基因工程菌E.coli A_(56)(pPA_(22))中试研究,在500升发酵罐考察该菌株生物合成青霉素酰化酶的工艺条件,发酵温度22.5℃,通气比1∶0.4,搅拌转速70转/分。同时还考察了不同浓度苯乙酸和苯乙酸加入时间。试验证明低浓度的溶解氧对酰化酶合成有利。发酵过程pH控制范围:生长期7.2～7.5,酶合成期7.5～8.0,发酵末期8.2～8.5。500升发酵罐最高酶产量达215.9u/100ml。

The Pencillin acylase gene E. coli A_(56) (pPA_(22)) was studies in piolot plant. It was investigated the strain on biosynthesis of Pencillin acylase in 500 litre fermenter. The optimum index of seed culture quality and fermentation condition was studied and confirmed: the optimum temperature for Pencillin acylase synthesis was 22.5℃, the ratio of aeration is 1:0.4, the agitation speed is 70 r.p.m. Pencillin acylase is induced by phenylacetic acid (PAA). The effect of PAA had been studied at different concentrations and adding times. The effect of dissolved oxygen was examined, rather low level dissolved oxygen seems preferable to the Pencillin acylase synthesis.The pH value was controlled at 7.2-7.5 in trophophase at7.5-7.8 in idiophase, and at 8.2-8.5 in the end of fermentation respectively. The higher productivity of Penicillin acylase(215.9u/100ml)was obtained in pilot-plant.