Center for Advanced Biotechnology and Medicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854-8021, USA.
Pfizer Global Research and Development, La Jolla Laboratories, San Diego, CA 92121, USA.
Structure. 2009 Dec 9;17(12):1625-1635. doi: 10.1016/j.str.2009.09.016.
Novel inhibitors are needed to counteract the rapid emergence of drug-resistant HIV variants. HIV-1 reverse transcriptase (RT) has both DNA polymerase and RNase H (RNH) enzymatic activities, but approved drugs that inhibit RT target the polymerase. Inhibitors that act against new targets, such as RNH, should be effective against all of the current drug-resistant variants. Here, we present 2.80 A and 2.04 A resolution crystal structures of an RNH inhibitor, beta-thujaplicinol, bound at the RNH active site of both HIV-1 RT and an isolated RNH domain. beta-thujaplicinol chelates two divalent metal ions at the RNH active site. We provide biochemical evidence that beta-thujaplicinol is a slow-binding RNH inhibitor with noncompetitive kinetics and suggest that it forms a tropylium ion that interacts favorably with RT and the RNA:DNA substrate.
需要新型抑制剂来对抗 HIV 耐药变体的快速出现。HIV-1 逆转录酶 (RT) 具有 DNA 聚合酶和核糖核酸酶 H (RNH) 酶活性，但已批准的抑制 RT 的药物针对聚合酶。针对新靶点（如 RNH）的抑制剂应该对所有当前的耐药变体有效。在这里，我们展示了 HIV-1 RT 和分离的 RNH 结构域的 RNH 活性部位结合的 RNH 抑制剂 beta-thujaplicinol 的 2.80 A 和 2.04 A 分辨率晶体结构。beta-thujaplicinol 在 RNH 活性部位螯合两个二价金属离子。我们提供了生化证据表明 beta-thujaplicinol 是一种具有非竞争动力学的慢结合 RNH 抑制剂，并提出它形成一个与 RT 和 RNA:DNA 底物相互作用良好的三价氧离子。
