Targeting Trypanosoma brucei S-adenosylmethionine decarboxylase in Drug Discovery

药物发现中的靶向布氏锥虫 S-腺苷甲硫氨酸脱羧酶

基本信息

批准号：
8034697
负责人：
Nahir Velez
金额：
$ 2.92万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-03-01 至 2013-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8034697
关键词：
Adenosylmethionine Decarboxylase Affinity Africa Africa South of the Sahara African Trypanosomiasis Alanine Allosteric Regulation Amino Acids Blood Cations Cell physiology Cells Complex DL-alpha-Difluoromethylornithine Data Decarboxylation Development Disease Enzymes Future Genetic Transcription Glutathione Goals Health Homologous Gene Human Insecta Kinetics Lead Left Leishmania donovani Libraries Maintenance Metabolic Pathway Mutagenesis N-terminal Ornithine Decarboxylase Parasites Parasitic Diseases Pathway interactions Patients Pharmaceutical Preparations Pharmacotherapy Play Polyamines Production Proteins Protozoa Putrescine Resistance Role S-Adenosylmethionine Scanning Spermidine Sulfhydryl Compounds Testing Toxic effect Translations Trypanosoma Trypanosoma brucei brucei Trypanosoma cruzi Trypanosomiasis Tsetse Flies Work carbanion cell growth chemical genetics chemotherapeutic agent chemotherapy cofactor decarboxylase inhibitor drug development drug discovery high throughput screening in vivo inhibitor/antagonist insight mutant novel research study small molecule small molecule libraries species difference suicide inhibitor tool development trypanothione

项目摘要

DESCRIPTION (provided by applicant): Human African Trypanosomiasis (HAT), commonly called sleeping sickness, is caused by single-celled parasites, Trypanosoma brucei, which are transmitted to humans by infected tsetse flies. Trypanosomiasis has a profound impact on the health of a large number of people in sub-Saharan Africa. It is fatal if left untreated and current drug therapy is problematic because of toxicity and emerging resistance. The polyamine biosynthetic pathway is a validated target for the development of drugs against HAT and the emerging evidence provides a compelling case that S-adenosylmethionine decarboxylase (AdoMetDC) is a highly promising target for the development of new anti-trypanosomal agents. AdoMetDC catalyses the ratelimiting step in the production of the polyamine spermidine from putrescine. Mammalian AdoMetDC is a homodimer that uses a pyruvoyl group as a cofactor to stabilize the carbanion intermediate formed during the decarboxylation of AdoMet. Recently, our lab demonstrated that the trypanosomatid AdoMetDC is regulated by a unique mechanism, heterodimer formation with a catalytically dead AdoMetDC homolog. This protein, designated prozyme, forms a high-affinity heterodimer with AdoMetDC and increases its activity by >1,000-fold. Further we confirmed that the heterodimer is the functional enzyme in vivo. My primary goals are to elucidate the mechanisms that regulate the AdoMetDC activation by the prozyme and to identify and characterize novel AdoMetDC inhibitors essential for the development of new anti-trypanosomal drugs. In order to do that, I will first focus on the identification of crucial amino acid residues involved in the activation in an attempt to gain insights into the mechanism of allosteric regulation. Next I will characterize species differences in the activation of AdoMetDC by prozyme by comparing the T. brucei AdoMetDC/prozyme complex to the homologs from T. cruzi and L. donovani. Finally I will perform a high-throughput screen (HTS) of a small molecule compound library to identify novel inhibitors of T. brucei AdoMetDC and to test these for activity against cultured parasites. Upon completion of these studies I will have identified and validated a number of novel inhibitors of AdoMetDC for future lead optimization studies that may lead to the discovery of new, less toxic drugs for the treatment of HAT. Project Narrative: Human African Trypanosomiasis is a insect borne disease that is fatal if untreated, yet current drug therapies are toxic and difficult to administer. The work described in this proposal characterizes an essential enzyme that has unique features in the parasite, with the goal of developing new chemotherapeutic agents against this devastating disease.

描述（由申请人提供）：通常称为睡眠病的人类非洲锥虫病（HAT）是由单细胞寄生虫，Brucei锥虫引起的，这些锥虫是通过受感染的TSETSE FLIE传播给人类的。锥虫病对撒哈拉以南非洲的许多人的健康有深远的影响。如果未治疗，并且由于毒性和耐药性，目前的药物治疗是有问题的，那将是致命的。多胺生物合成途径是针对HAT开发药物的验证靶标，而新兴证据则提供了一种令人信服的案例，即S-腺苷甲硫代氨酸脱羧酶（ADOMENTDC）是发展新的抗tryosomamal剂的高度希望的目标。 ADOMETDC在腐霉菌中生产多胺精子的产生时，将比率的步骤催化。哺乳动物ADOMETDC是一种同型二聚体，它使用曲武型组作为辅助因素来稳定Adomet脱羧期间形成的carbanion中间体。最近，我们的实验室证明了锥虫的ADOMOTDC为由独特的机制调节，异二聚体形成，具有催化死亡的AdometDC同源物。该蛋白质被指定为prozyme，形成具有ADOMETDC的高亲和力异二聚体，并将其活性增加> 1,000倍。此外，我们证实异二聚体是体内功能性酶。我的主要目标是阐明prozyme调节ADOMETDC激活的机制，并识别和表征新型的ADOMETDC抑制剂，对于开发新的抗异神体药物至关重要。为此，我首先将重点放在鉴定激活中涉及的关键氨基酸残基上，以尝试洞悉变构调节机制。接下来，我将通过将T. adomentdc/Prozyme复合物与T. Cruzi和L. donovani的同源物进行比较，来表征prozyme激活AdometDC中的物种差异。最后，我将对小分子化合物文库进行高通量筛选（HTS），以识别t. brucei adometDC的新型抑制剂，并测试这些抑制剂，以实现针对培养的寄生虫的活性。这些研究完成后，我将确定并验证了许多新型ADOMETDC的新型抑制剂，以进行未来的铅优化研究，这些研究可能导致发现新的，毒性较小的药物来治疗HAT。项目叙述：非洲人类锥虫病是一种昆虫传播疾病，如果未治疗，但目前的药物疗法是有毒且难以给药的。该提案中描述的工作是一种基本酶，该酶在寄生虫中具有独特的特征，目的是开发针对这种毁灭性疾病的新化学治疗剂。