Objectives A redox potential-driven fermentation, maintaining dissolved oxygen at a prescribed level while simultaneously monitoring the changes of fermentation redox potential, was developed to guide the cultivation progress of recombinant protein expression. Results A recombinant E. coli harboring prolinase-expressing plasmid (pKK-PepR2) was cultivated using the developed process. Two distinct ORP valleys were noticeable based on recorded profile. The first ORP valley is equivalent to the timing for the addition of inducing agent, and the second ORP valley serves to guide the timing for cell harvesting. The final prolinase activity is 0.172 μmol/mg/min as compared to that of 0.154 μmol/mg/min where the optical density was employed to guide the timing of inducer addition and an empirically determined length of the cultivation. Conclusion The developed process can be further modified to become an automatic operation.

中文翻译：

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用于重组蛋白表达的氧化还原电位驱动发酵工艺的开发

目的开发一种氧化还原电位驱动的发酵，将溶解氧保持在规定水平，同时监测发酵氧化还原电位的变化，以指导重组蛋白表达的培养进程。结果使用开发的方法培养了携带表达脯氨酸酶的质粒（pKK-PepR2）的重组大肠杆菌。根据记录的轮廓可以看到两个不同的 ORP 谷。第一个 ORP 谷相当于添加诱导剂的时间，第二个 ORP 谷用于指导细胞收获的时间。最终的脯氨酸酶活性为 0.172 μmol/mg/min，而 0.154 μmol/mg/min 则采用光密度来指导添加诱导剂的时间和经验确定的培养长度。