Fairlie W D, Zhang H, Brown P K, Russell P K, Bauskin A R, Breit S N
Centre for Immunology, St. Vincent's Hospital and the University of New South Wales, Sydney, Australia.
Gene. 2000 Aug 22;254(1-2):67-76. doi: 10.1016/s0378-1119(00)00295-x.
The methylotrophic yeast, Pichia pastoris, has been used to express both human and murine macrophage inhibitory cytokine-1 (MIC-1), a transforming growth factor beta (TGF-beta) superfamily cytokine. This is the first report of the expression of a correctly folded TGF-beta superfamily protein in a microbial organism. The protein is secreted in its correctly folded dimeric form at milligram per litre quantities, which are significantly higher than we have been able to achieve using mammalian expression systems. Purification schemes are described, and the purified protein is immunologically identical to protein produced in a mammalian expression system. Protein expression was influenced by a number of factors, most significantly by the concentration of methanol used during the induction phase. However, with very high levels of MIC-1 induction, substantial amounts of MIC-1 monomer were also secreted.
甲基营养型酵母毕赤酵母已被用于表达人源和鼠源巨噬细胞抑制细胞因子1（MIC-1），一种转化生长因子β（TGF-β）超家族细胞因子。这是在微生物中表达正确折叠的TGF-β超家族蛋白的首次报道。该蛋白以正确折叠的二聚体形式分泌，产量可达每升数毫克，这明显高于我们使用哺乳动物表达系统所能达到的产量。文中描述了纯化方案，纯化后的蛋白与在哺乳动物表达系统中产生的蛋白在免疫学上相同。蛋白表达受多种因素影响，其中最显著的是诱导阶段所用甲醇的浓度。然而，在非常高的MIC-1诱导水平下，也会分泌大量的MIC-1单体。
