摘要
在10 L发酵罐中利用重组毕赤酵母诱导表达猪α干扰素(pIFN-α),考察甲醇/山梨醇共混诱导策略对pIFN-α表达水平提高和能量(NADH)再生效率的影响。结果表明:在诱导稳定期,甲醇/山梨醇共混诱导可弱化细胞的甲醇代谢,有利于缓解毒副中间产物(过氧化氢、甲醛等)的生成积累;以0.785 g/(L.h)的速率缓慢共混流加山梨醇时,pIFN-α抗病毒活性最大,最高活性可达1.8×107IU/mL,与30℃常温甲醇单独诱导(最高活性1.0×104IU/mL)和20℃低温甲醇单独诱导(最高活性1.4×106IU/mL)相比,活性均大幅提高,且胞外pIFN-α的降解减缓;发酵体系的抗高甲醇浓度冲击能力有效提高,发酵生产的稳定性增强;能量利用效率大幅提高,NADH的再生利用效率提高了29%~84%。
Abstract: The effects of methanol/sorbitol co-feeding strategy on porcine interferon-a (pIFN-a) produc- tion by recombinant Pichia pastoris and the relevant energy (NADH) regeneration efficiency during induc- tion phase were investigated in a 10-L fermentor. The results showed that methanol/sorbitol co-feeding weakened the methanol metabolism in cells and relieved accumulation of the toxic intermediate metabo- lites (formaldehyde, H202, etc. ). Compared with 30 ℃pure methanol induction strategy (maximum pIFN-a antiviral activity 1.0 × 104 IU/mL ) and 20℃ low temperature pure methanol induction strategy (maximum pIFN-a antiviral activity 1.4 × 106 IU/mL) , methanol/sorbitol co-feeding strategy and sorbi- tol feeding rate at 0. 785 g/(L·h) could improve pIFN-a antiviral activity, and the highest pIFN-a anti- viral activity reached 1.8 × 107 IU/mL. In addition, the targeted protein degradation was also relieved when using the co-feeding strategy. With the co-feeding strategy, the resistant ability against high metha-nol concentration of the fermentation process was enhanced for ensuring the fermentation stability. Using the co-feeding strategy, energy utilization rate was improved and NADH reutilization efficiency was raised from 29% to 84%.
出处
《生物加工过程》
CAS
CSCD
2012年第2期55-62,共8页
Chinese Journal of Bioprocess Engineering
基金
国家重点基础研究发展计划(973计划)资助项目(2007CB714303)
上海科学技术委员会农业科技重点基金资助项目(073919108)
关键词
山梨醇
毕赤酵母
猪Α干扰素
sorbitol
Pichia pastoris
porcine interferon-a