MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF A SECRETED LIPASE IN LEISHMANIA

利什曼原虫分泌的脂肪酶的分子和生物化学特征

• 批准号: 7381355
• 负责人: ALISON M SHAKARIAN
• 金额: $ 10.44万
• 依托单位: UNIVERSITY OF RHODE ISLAND
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7381355
• 关键词: MOLECULAR; BIOCHEMICAL; CHARACTERIZATION; SECRETED; LIPASE

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The proposed research is designed to contribute to the understanding of mechanisms of Leishmania survival, growth and development. The disease spectrum of leishmaniasis ranges from mild self-limiting cutaneous ulcers to a potentially fatal visceral infection, each dependant on the species of infectious parasite. Specific proteins secreted by Leishmania enable the organisms to sense, respond to, and alter their environment. Such secreted proteins are thus potential targets for the development of new compounds to prevent or treat this diseases. Currently there is no vaccine available for the prevention of transmission of these parasites. Toxic antimony compounds have been used unsuccessfully. Lipases are lipolytic enzymes that hydrolyze the ester bond of triglycerides. In other systems, lipase activity is involved in the reorganization of membrane structure, cell signaling or nutrient acquisition. These observations suggest that lipase activity is essential for Leishmania although presently the biological significance of this enzyme has not been proven experimentally. The working hypothesis, that lipase is essential to Leishmania, will be tested. The following approaches to determine the role of this enzyme in the parasite life cycle are planned: 1) The full-length copy of the lipase gene will be identified and characterized; the expression of lipase will be examined though out the parasite developmental life cycle and the phylogenic conservation of lipase among kinetoplastid protozoa will be determined. 2) Null-mutants deficient in lipase activity will be generated and tested for viability. 3) The lipase gene will be expressed as a recombinant protein and assayed for substrate preference. In addition, various classes of organophosphate inhibitors of lipase will be tested to determine the sensitivity of the leishmanial lipase to these compounds.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。拟议的研究旨在有助于了解利什曼原虫生存，生长和发育的机制。利什曼病的疾病谱范围从轻度自限性皮肤溃疡到潜在致命的内脏感染，每种都取决于感染性寄生虫的种类。利什曼原虫分泌的特定蛋白质使生物体能够感知，响应和改变它们的环境。因此，这种分泌的蛋白质是开发新化合物以预防或治疗这种疾病的潜在靶标。目前还没有预防这些寄生虫传播的疫苗。有毒的锑化合物已被使用，但未成功。脂肪酶是水解甘油三酯的酯键的脂解酶。在其他系统中，脂肪酶活性涉及膜结构的重组、细胞信号传导或营养物质获取。这些观察结果表明，脂肪酶的活性是必不可少的利什曼原虫，虽然目前这种酶的生物学意义尚未得到实验证明。工作假设，脂肪酶是必不可少的利什曼原虫，将进行测试。计划采用以下方法确定该酶在寄生虫生活周期中的作用：1）将鉴定和表征脂肪酶基因的全长拷贝;将在寄生虫发育生活周期中检查脂肪酶的表达，并将确定动质体原生动物中脂肪酶的促生长保守性。2)将产生脂肪酶活性缺陷的空突变体并检测活力。3)脂肪酶基因将表达为重组蛋白，并测定底物偏好。此外，将测试脂肪酶的各种类型的有机磷酸酯抑制剂，以确定利什曼原虫脂肪酶对这些化合物的敏感性。