FATTY ACID BIOSYTHESIS IN CRYPTOSPORIDIUM PARVUM

小隐孢子虫中的脂肪酸生物合成

• 批准号: 6336055
• 负责人: GUAN ZHU
• 金额: $ 19.65万
• 依托单位: TEXAS A&M UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-15 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6336055
• 关键词: Cryptosporidium; enzyme activity; fatty acid biosynthesis; fatty acid synthase; gene expression; laboratory rabbit; microorganism metabolism; protein localization

DESCRIPTION: (Adapted from Applicant's Abstract) Cryptosporidium parvum causes one of the opportunistic infections (OI) in AIDS patients for which no treatment is yet known. Although many drugs have been tested against the OI, knowledge about the presence of target enzymes, biosynthetic pathways, and expression or regulation are virtually unknown. The applicant's preliminary data indicate that several fatty acid synthase (FAS) genes are present in C. parvum (CpFAS) and that their size, organization and functional domains differ from those of humans. These genes appear to be functional, since their transcripts were detected in sporozoites and intracellular stages and the growth of C. parvum in vitro was inhibited by a FAS inhibitor. The discovery of CpFAS genes suggests that this apicomplexan might synthesize fatty acids de novo, thus providing clues for drug development against cyptosporidiosis. Because most parasitic protozoa are auxotrophs for fatty acids, this discovery also opens a new vista for protozoan biochemistry. The investigator's long term goal is to study the potential of apicomplexan fatty acid biosynthesis as a useful target for drug development. The specific aims of this proposal are: 1.Characterize the CpFAS gene structure, transcription level and subcellular localization during the life cycle of the parasite. 2. Elucidate the function of CpFAS by the analysis of substrate preference, intermediate and final fatty acid products using recombinant CpFAS proteins expressed in bacteria or yeast 3.Determine whether fatty acid biosynthesis can serve as a rational target for drug development by screening FAS analogues against C. parvum in vitro and in vivo. Completion of these specific aims will either support or refute the investigator's hypothesis that fatty acid biosynthesis in C. parvum is sufficiently different from its host to be exploited for drug design target against cryptosporidiosis. The outcome expected is to overcome a major obstacle for therapy against this OI of AIDS patients.

描述：（改编自申请人的摘要）小隐孢子虫的原因 艾滋病患者中的机会性感染 (OI) 之一，目前尚无 治疗方法尚不清楚。尽管许多药物已经针对成骨不全症进行了测试， 关于目标酶的存在、生物合成途径和 表达或调节实际上是未知的。申请人的初步 数据表明，一些脂肪酸合酶（FAS）基因存在于 C. parvum (CpFAS) 以及它们的大小、组织和功能域不同 来自人类。这些基因似乎是有功能的，因为它们 在子孢子和细胞内阶段检测到转录本 FAS 抑制剂可抑制 C. parvum 的体外生长。的发现 CpFAS 基因表明这种 apicomplexan 可能合成脂肪酸 novo，从而为抗隐孢子虫病的药物开发提供线索。 由于大多数寄生原生动物都是脂肪酸营养缺陷型，这一发现 也为原生动物生物化学开辟了新的前景。研究者的长期 目标是研究 apicomplexan 脂肪酸生物合成作为生物合成的潜力 药物开发的有用目标。该提案的具体目标是： 1.表征CpFAS基因结构、转录水平和亚细胞 寄生虫生命周期中的定位。 2. 阐明功能 通过底物偏好、中间体和最终脂肪的分析来分析 CpFAS 使用在细菌或酵母中表达的重组 CpFAS 蛋白的酸产品 3.确定脂肪酸生物合成是否可以作为合理的目标 通过在体外和体内筛选针对 C. parvum 的 FAS 类似物来开发药物 体内。完成这些具体目标将支持或驳斥 研究者的假设是 C. parvum 中的脂肪酸生物合成是 与其宿主有足够的不同，可用于药物设计目标 对抗隐孢子虫病。预期的结果是克服一个主要障碍 用于治疗艾滋病患者的这种 OI。