摘要
用2 L 全自动发酵罐观察 Ec 108(pPAHD 1)青霉素酰化酶基因的表达,发现对数前期生物量扩增时,溶解氧以相对饱和度≥80%为宜,而产酶阶段则要求相对饱和度约为5%。应根据溶氧曲线变化特征指导诱导剂苯乙酸的补加时机和剂量,以每次补加0.03～0.05%为佳。在罐压29 kPa、通气比1:0.5的恒温条件下,借助上述手段,可使最高酶活水平达342u/100 ml(NIPAB 法),比摇瓶发酵提高1.8倍。
The expression of penicillin G.acylase gene of hybrid strain Ec108 (pPAHDl)was studied in a 2-liter automatic fermenter.A relatively high levelof dissolved oxygen,which was no less than 80% saturation was needed inearly logarithmic growth phase of the bacteria,while a relatively low level around5% saturation was required in the stage of acylase production.The right timeand amount for the addition of phenylacetic acid,an inducer,could be decidedfrom the specific dissolved oxygen curve.For extending the period of effectivesynthesis of acylase,it was preferable to control the phenylacetic acid concentrationwithin 0.03～0.05% in each addition.Under fermenter's pressure 29kPa,andventilation ratio 1:0.5 at constant temperature,and with the dissolved oxygenand phenylacetic acid being controlled,the maximal acylase activity could reach342u/100ml at 28h(NIPAB method),which was 1.8 fold higher in comparisonwith the flaskshaking fermentation.
出处
《中国医药工业杂志》
CAS
CSCD
北大核心
1992年第4期145-148,共4页
Chinese Journal of Pharmaceuticals
关键词
青霉素酰化酶
表达
溶解氧
诱导剂
penicillin G acylase
expression
dissolved oxygen
inducer
