文献类型：期刊文献

中文题名：pH对毕赤酵母表达重组人复合α干扰素的降解影响

英文题名：Effect of pH on Proteolytic Degradation of Consensus Interferon-α Expressed by Pichia pastoris

作者：张盛[1];郝玉有[1];储炬[1];王永红[1];郭美锦[1];张嗣良[1];庄英萍[1]

机构：[1]华东理工大学生物反应器工程国家重点实验室,上海200237

年份：2008

卷号：24

期号：1

起止页码：164

中文期刊名：生物工程学报

外文期刊名：Chinese Journal of Biotechnology

收录：CSTPCD;;Scopus;北大核心:【北大核心2004】；CSCD:【CSCD2011_2012】；PubMed;

基金：国家自然科学基金(No.30560006);上海市曙光跟踪计划(No.06GG07)~~

语种：中文

中文关键词：pH;cIFN;降解;流式细胞仪

外文关键词：pH, consensus interferon, protease, degradation, flow cytometry, Pichia pastoris

摘要：使用Pichiapastoris表达重组人复合0c干扰素（cIFN）会发生降解、聚合等不均一表达的现象。在5L发酵罐中考察了不同诱导pH对cIFN表达产生降解的影响，结果发现在适合酵母生长的pH3．0-7．0范围内，当诱导pH为4．0~5．0时，cIFN不均一表达现象最少，生物活性达到2．5×1O^8IU／mL。通过测定发酵液中总蛋白酶活和细胞活性寻找了cIFN降解出现的原因：发现低诱导pH下细胞死亡率升高释放更多酶系，高诱导pH下蛋白酶活性明显增大，两者都使蛋白酶作用加强，加剧cIFN的降解；特别是诱导pH为7．0时，适宜的pH使蛋白酶酶活陡升，将cIFN完全降解。
We observed the heterogeneity of consensus interferon （clFN） expressed by Pichia Pastoris, such as aggregation and degradation. The effect of induction pH on degradation of cIFN was studied in a 5-L bioreactor. The heterogeneity of cIFN was less serious when induced at pH 4.0-5.0. The bioactivity of the fermentation supematant reached 2.5×10^8 IU/mL when pH was controlled between 4.0 and 5.0. To seek the reason of cIFN degradation, we analyzed the activity of protease and cell mortality by flow cytometry. At lower pH, cell mortality was higher and more protease was released. Protease activity increased at higher pH. The proteolytic degradation of cIFN was enhanced at either high or low pH. The cIFN was degraded entirely when pH was 7.0, where the protease had its optimal pH.