Effect of Ammonium Concentration on the Cultivation of Recombinant Escherichia coli Producing Penicillin G acylase

培養基中銨濃度對基因改質大腸桿菌醱酵生產盤尼西林醯胺酵素之影響

劉永銓(Yung-Chuan Liu) ； 陳光宇(Kaung-Yu Cheng)

《Journal of the Chinese Institute of Chemical Engineers》 31卷6期 (2000/11) Pp. 601-607

https://doi.org/10.6967/JCICE.200011.0601

摘要

本研究以一經基因改變帶有pGL-5質體之大腸桿菌，醱酵生產盤尼西林醯胺酵素（PGA），並探討不同銨濃度對醱酵造成之影響。在培養基中三種不同硫酸銨濃度分別為0.5%，3%，5%，結果顯示在這些不同硫酸銨濃度下，醱酵全程中均僅有小量醋酸、乳酸及丙酮酸副產物產生，然而在3%硫酸銨時，有較多之乳酸之累積。而在5%硫酸銨時，於醱酵10小時後開始有大量丙酮酸之累積。培養基中硫酸銨濃度愈高，菌體生長之遲滯期愈長。在3%及5%硫酸銨之培養時，菌體生長速度均為後對數生長期大於前-中對數生長期。在5%硫酸銨下，菌體生長及PGA之生產明顯受到抑制。

並列摘要

The effect of ammonium on the cultivation of r E. coli UP1, a penicillin G acylase (PGA) hyper-producer, was investigated. While r E. coli UPl was grown under three different concentrations of ammonium, i.e., 0.5%, 3% and 5% ammonium sulfate, respectively, it was found that the higher the ammonium sulfate concentration, the longer the lag phase. Cell growth and PGA activity expression were not inhibited in the 0.5-3% ammonium sulfate cases, whereas significant regulation of cell growth was found in the 5 % ammonium sulfate case. The time profile of organic acids was affected by the ammonium sulfate concentration in the medium. In the 3% ammonium case, a higher amount of lactic acid was observed. In contrast, traces of pyruvic acid were detected during fermentation except for the case with 5% ammonium sulfate, where pyruvic acid accumulated significantly from 10 h of fermentation.

並列關鍵字

Penicillin G acylase ； E. coli ； Ammonium ； Metabolic Pathway