Parameters-based Association Analysis for Recombinant Phytase Expression in Genetically Engineered Pichia pastoris at Transition Phase
Parameters-based Association Analysis for Recombinant Phytase Expression in Genetically Engineered Pichia pastoris at Transition Phase
复制标题
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
G. Mei
中科院分区：
文献类型：
--
作者：
G. Mei
微生物发酵过程是一个多尺度参数的复杂生物系统。本报告描述了基于在线和离线参数的关联分析，重组植酸酶在基因工程毕赤酵母中的表达过渡期。通过对耗氧率（OUR）和溶解氧（DO）在线参数的关联分析，发现甘油和葡萄糖在转录水平上对aox基因（醇氧化酶）有不同程度的抑制作用，其中葡萄糖的抑制作用较强。从关键酶活性来看，在过渡期，重组毕赤酵母糖酵解途径和三羧酸循环途径的代谢通量较低，HMP途径的代谢通量较高，甲醇氧化成为主要途径。这些观察结果与在线和间接参数（如pH、OUR、CER和RQ）的关联分析数据一致。此外，该研究揭示了OUR和CER的逐渐增加标志着PAOX 1在过渡期的成功诱导。
Microbial fermentation process is a complex bio-system of multi-scale parameters. This report describes on-line and off-line parameters-based association analysis for recombinant phytase expression in genetically engineered Pichia pastoris at transition phase. According to the association analysis of on-line parameters of oxygen uptake rate (OUR) and dissolved oxygen (DO), the aox gene (alcohol oxidase) was repressed at transcription level by glycerol and glucose at different degrees, with glucose as a stronger repressor. Based upon the key enzymes' activities, at the transition phase, the recombinant Pichia patoris had lower metabolic fluxes for glycolysis pathway and tricarboxylic acids cycle pathway; higher metabolic flux for HMP pathway, with the oxidation of methanol became a major pathway. These observations were consistent with the data from the association analysis for on-line and indirect parameters such as pH, OUR, CER and RQ. Additionally, this study revealed that gradual increase of OUR and CER signaled the successful induction of the P AOX1 at the transition phase.