Kern G, Handel T, Marqusee S
Department of Molecular and Cell Biology, University of California, Berkeley, 94720, USA.
Protein Sci. 1998 Oct;7(10):2164-74. doi: 10.1002/pro.5560071014.
The RNase H domain from HIV-1 (HIV RNase H) encodes an essential retroviral activity. Refolding of the isolated HIV RNase H domain shows a kinetic intermediate detectable by stopped-flow far UV circular dichroism and pulse-labeling H/D exchange. In this intermediate, strands 1, 4, and 5 as well as helices A and D appear to be structured. Compared to its homolog from Escherichia coli, the rate limiting step in refolding of HIV RNase H appears closer to the native state. We have modeled this kinetic intermediate using a C-terminal deletion fragment lacking helix E. Like the kinetic intermediate, this variant folds rapidly and shows a decrease in stability. We propose that inhibition of the docking of helix E to this folding intermediate may present a novel strategy for anti HIV-1 therapy.
来自HIV-1的核糖核酸酶H结构域（HIV核糖核酸酶H）编码一种必需的逆转录病毒活性。分离出的HIV核糖核酸酶H结构域的重折叠显示出一种动力学中间体，可通过停流远紫外圆二色性和脉冲标记氢/氘交换检测到。在这个中间体中，链1、4和5以及螺旋A和D似乎是有结构的。与来自大肠杆菌的同源物相比，HIV核糖核酸酶H重折叠的限速步骤似乎更接近天然状态。我们使用缺乏螺旋E的C末端缺失片段对这个动力学中间体进行了建模。与动力学中间体一样，这个变体折叠迅速且稳定性降低。我们提出，抑制螺旋E与这个折叠中间体的对接可能是一种抗HIV-1治疗的新策略。
