感光受体外周蛋白结合蛋白对虫荧光素酶体外折叠的促进作用

Improvement of luciferase refolding in vitro by peripherin-binding protein

目的 探讨感光受体外周蛋白结合蛋白 (PBP)在体外是否有促进变性蛋白质复性的作用。虫荧光素酶用盐酸胍变性 ,然后在 PBP、HSP70、HSP6 0存在下进行体外复性 ,用虫荧光素酶分析系统检测该酶的复性程度。结果显示 PBP对虫荧光素酶的复性能力很低 ,当与 HSP70同时作用时 ,酶活力明显高于 PBP或 HSP70组 ,而 PBP与 HSP6 0组合对酶的复性能力较HSP6 0组未见有明显差异 ;当 PBP,HSP70 ,HSP6 0三者同时存在时 ,酶活力恢复率最高。去除复性缓冲液中的 ATP及其再生系统 ,酶活力的复性率明显下降。结果表明 PBP具有协助 HSP70 ,在 ATP依赖的情况下促进变性虫荧光素酶体外复性的分子伴侣功能。

Objective The possibility of peripherin binding protein (PBP) to improve the refolding of denatured luciferase in vitro was investigated. Luciferase was denatured with 6mol/L guanidine hydrochlori and then added into refolding buffer containing different molecular chaperone including PBP, HSP70, HSP60 and their combinations. Sample was analyzed with luciferase assay solution. The enzyme activity raised a little after PBP or HSP70 being added, however, the recovery of enzyme activity had significantly raised when the reaction was conducted with PBP plus HSP70. But PBP+HSP60 and HSP70+HSP60 have no such effect compare to HSP60. PBP+HSP70+HSP60 has the most refolding yield of denatured enzyme in all molecular chaperones. The refolding was markedly decreased after ATP being depleted . It is concluded that PBP cooperates with HSP70 and to improve productive folding of chemically denatured luciferase in ATP dependent in vitro.