疏水层析法复性重组人γ干扰素

Refolding of recombinant human interferon-γ by hydrophobic interaction chromatography

重组人γ-干扰素(rhIFN-γ)在大肠杆菌中高效表达,并形成包涵体.利用疏水作用层析(HIC)法对rhIFN-γ进行复性.采用了等尿素梯度和线性尿素梯度两种复性方法,考察了线性尿素梯度下尿素梯度长度、尿素终浓度、流速和上样量对rhIFN-γ复性的影响.在优化的线性尿素梯度复性条件下,尿素浓度在10个柱体积内从6mol·L-1下降到2mol·L-1,流速为1ml·min-1、上样量为0.568mg时,rhIFN-γ的活性收率比稀释复性法提高6.5倍,蛋白质量收率为36%,比活达1.9×108IU·mg-1.

The recombinant human interferon-γ (rhIFN-γ) was overexpressed as inclusion bodies in Escherichia coli. After ultrasonic homogenization and centrifugation, inclusion bodies of rhIFN-γ were obtained. The inclusion bodies were then purified by coupling wash steps in Triton X-100 and finally were dissolved in 8 mol·L -1 urea. A refolding process by hydrophobic interaction chromatography (HIC) was proposed. Refolding methods with no urea gradient and linearly decreasing urea gradient were performed.The effects of final urea concentration, urea gradient length, flow rate and protein loading on the refolding were investigated in detail. Under the optimum condition in the refolding with linearly decreasing urea gradient, the activity yield of rhIFN-γ was 6.5 times of that in the dilution refolding process and the protein mass yield was up to 36% with specific activity 1.9×108 IU·mg -1.