摘要
大肠杆菌发酵表达的TRAIL蛋白经过两步纯化可得到纯度95%以上的活性蛋白,得率为40%。天然TRAIL蛋白为同源三聚体形式,在三聚体中心隐蔽结合Zn^(2+),Zn^(2+)可维持TRAIL蛋白天然结构的稳定性。研究发现在纯化后的重组可溶性TRAIL蛋白中添加Zn^(2+),并且Zn^(2+)与TRAIL单体的摩尔比例达到2:1时,TRAIL蛋白的活性达到最高。本文初步研究了TRAIL蛋白的体外活性稳定性问题,发现在添加了最适Zn^(2+)后的TRAIL蛋白保存溶液中添加25mmol/L LArg与50mmol/L L-Glu有助于抑制TRAIL蛋白活性下降、并可能长期稳定蛋白活性。
A simple and efficient process of two-step purification of soluble TRAIL protein was established. The purity of 95% and the total recovery of 40% were obtained. This process was suitable for industrialized manufacturing crystallographic. Studies showed that the soluble TRAIL had a homotrimeric structure, and an internal zinc atom was bound by the cysteine residues at position 230 of each subunit, which was crucial for trimer stability and biologic activity. TRAIL was not a stable protein, but a phenomenon was demonstrated that the addition Zn^2＋ of molar ratio to TRAIL monomer with 2 ： 1 in purified TRAIL solution and simultaneous addition of 25 mmol/L L-Arg and 50 mmol/L L-GIu to the purified TRAIL could dramatically stabilize its activity and reduce aggregation and precipitation.
出处
《工业微生物》
CAS
CSCD
2011年第1期9-14,共6页
Industrial Microbiology
基金
上海市重点学科建设项目资助(B505)
