HIV 1 PROTEASE W/ INHIBITOR ACETYL PEPSTATIN: ISOTHERMAL TITRATION CALORIMETRY

HIV 1 蛋白酶含抑制剂乙酰胃酶抑素：等温滴定量热法

• 批准号: 6122013
• 负责人: JASON S BARDI
• 金额: --
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-08-05 至 1998-08-04
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6122013
• 关键词: AIDS; behavioral /social science research tag; biological products; biomaterials; biomedical resource; communicable diseases; human tissue; immunology; lymphatic system; psychology; sexually transmitted diseases; technology /technique development; virus

Human Immunodeficiency Virus (HIV), which causes Acquired Immune Deficiency Syndrome (AIDS), replicates by packaging RNA copies of its genome into infectious particles (or virions) comprised of membrane and at least nine different proteins. This packaging, together with the entry of the virion into a cell, the reverse transcription of the viral RNA into DNA, and the subsequent insertion of this DNA into the host cell's chromosome comprises what might be thought of as the HIV life cycle. Any molecule that is essential to this process could be a potential target for antiretroviral therapy. HIV protease is the enzyme responsible for processing the gag/pol polyprotein into the various structural and enzymatic proteins necessary for the packaging of HIV into virions. If the effect of this enzyme is inhibited, infected cells are not able to produce virions to infect more cells. In clinical settings, there is a well correlated decrease in viral load in peripheral blood lymphocytes in patients taking protease inhibitors. However, HIV has no proofreading mechanism associated with its reverse transcriptase enzyme, and so the reverse transcription process is highly error prone. As a result of this, viral copies arise with mutations in the HIV protease enzyme that confer resistance to inhibitors. In patients this is seen as an increase in the viral load of the resistant viruses, which somehow retain affinity for the polyprotein cleavage sites that act as substrate while losing affinity for the protease inhibitors. We have used isothermal titration calorimetry to characterize the binding of the protease and the acetylated inhibitor pepstatin A. By performing similar characterizations on mutants of the protease with various inhibitors and substrates, we should be able to map the molecular origin of HIV drug resistance, which will be invaluable for the next generation of protease inhibitors.

人类免疫缺陷病毒（HIV），导致获得性免疫 缺乏综合征（艾滋病），复制包装RNA拷贝，其 基因组转化为由膜组成的感染性颗粒（或病毒体） 和至少九种不同的蛋白质 这种包装，连同 病毒体进入细胞，逆转录病毒， 病毒RNA进入DNA，随后将此DNA插入到 宿主细胞的染色体包含可能被认为是艾滋病毒的物质 生命周期 任何对这一过程至关重要的分子都可能是 抗逆转录病毒治疗的潜在靶点。 HIV蛋白酶是 负责将gag/pol多蛋白加工成 包装所需的各种结构蛋白和酶蛋白 转化为病毒体。 如果这种酶的作用被抑制， 被感染的细胞不能产生病毒体来感染更多的细胞。 在临床环境中，病毒感染的减少与此密切相关。 服用蛋白酶患者外周血淋巴细胞负荷 抑制剂的 然而，艾滋病毒没有相关的校对机制， 与它的逆转录酶， 转录过程非常容易出错。 结果， 病毒拷贝是由HIV蛋白酶的突变引起的， 赋予对抑制剂的抗性。 在患者中，这被视为 抵抗病毒的病毒载量增加， 保持对多蛋白切割位点的亲和力， 底物，同时失去对蛋白酶抑制剂的亲和力。 我们有 使用等温滴定量热法来表征 蛋白酶和乙酰化抑制剂胃酶抑素A。通过执行 类似的表征的突变体的蛋白酶与各种 抑制剂和底物，我们应该能够绘制出 艾滋病毒耐药性的起源，这将是非常宝贵的下一个 蛋白酶抑制剂的产生。