Structural Requirements for Sterol 14alpha-Demethylases

甾醇 14α-脱甲基酶的结构要求

基本信息

批准号：
8604398
负责人：
Galina I Lepesheva
金额：
$ 34.38万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-01-01 至 2015-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8604398
关键词：
Active Sites Address Alcohols Aldehydes Animal Model Animals Antifungal Agents Aspergillus Aspergillus fumigatus Azole resistance Azoles Binding Biochemical Biochemistry Biological Biophysics Candida Candida albicans Catalysis Cell division Cells Cessation of life Chagas Disease Characteristics Chemicals Complex Cytochrome P450 Development Distant Drug Design Drug Targeting Drug resistance Enzyme Inhibitor Drugs Enzyme Inhibitors Enzymes Family Formic Acids Funding Future Goals Grant Growth and Development function Health Heme Iron Human Immunocompromised Host Immunologic Deficiency Syndromes Infection Investigation Knowledge Lanosterol Lead Learning Leishmania Leishmaniasis Ligands Mediating Membrane Minor Mixed Function Oxygenases Modification Molds Molecular Mycoses Organism Pharmaceutical Preparations Phylogeny Predisposition Progress Reports Protozoa Reaction Research Resistance Roentgen Rays Site-Directed Mutagenesis Sterol Biosynthesis Pathway Sterols Structure System Testing Trypanosoma Trypanosoma brucei brucei Trypanosoma cruzi Trypanosomatina Trypanosomiasis Yeasts analog base cholesterol biosynthesis design drug candidate drug development fungus global health human migration in vivo inhibitor/antagonist killings member membrane biogenesis methyl group mouse model mutant novel pathogen preference pyridine resistant strain scaffold

项目摘要

DESCRIPTION (provided by applicant): Sterol 14?-demethylase (CYP51) is the most widely distributed and perhaps the oldest of the > 13,000 P450s known to date. This monooxygenase catalyzes a unique three step reaction (14?-methyl ->14?- alcohol->14?-aldehyde->14?-demethylated product plus formic acid) removing the 14?-methyl group from the initial cyclized intermediate in sterol biosynthesis, i.e. lanosterol in cholesterol biosynthesis. CYP51 is a drug target in eukaryotic pathogens because the reaction it catalyzes is essential for membrane formation and therefore loss of this activity is lethal. It has been studied extensively as a drug target in yeast and filamentous fungi where azoles that bind to the CYP heme iron have been found to be very effective drugs. Other eukaryotic human pathogens have not been studied in great detail and we have begun a detailed analysis of CYP51 in trypanosomes and leishmania, including whether it can serve as a drug target for killing these organisms which cause more than one hundred million deaths each year in the 'third world' and is becoming a serious global problem, mainly due to human migration and growing immunodeficiency. Our detailed investigation of CYP51 from Trypanosomatidae has been supported during the first two funding cycles of this grant, and during this current cycle we have also characterized novel chemical scaffolds which we believe are the basis of very efficient inhibitors of CYP51 from protozoa. This competing renewal application consists of three Specific Aims. First, is structure-based development of selective inhibitors for protozoan CYP51s. Here we will synthesize derivatives of the three original scaffolds we discovered (azole, pyridine and substrate based) and analyze the best of these derivatives in four test systems: protozoa themselves, human cells, human cells infected with protozoa and mouse models for Chagas disease. Second, we will test these scaffolds and their derivatives as potential drugs for treatment of infection by Candida albicans and Aspergillus (A) fumigatus and A. flavus. These fungi are highly pathogenic in humans, especially in immunocompromised patients, and after characterization by biochemistry and biophysics (including X-ray structure) of their CYP51s we will establish which scoffids and derivatives will be most effective for antifungal drug design. Third, we will compare structure-function characteristics of CYP51s from three different biological kingdoms (protozoa/fungi/human) to establish in detail the basis on which we can identify what features of both the enzymes and the inhibitors will lead to rational design of pathogen-selective drugs and drugs effective for CYP51-related azole resistance. Overall, the results arising from these studies will direct future approaches for drug development which will have major importance in global health.

描述（由申请人提供）：固醇14？ - 脱甲基酶（CYP51）是迄今为止已知的> 13,000 P450中最悠久的甲醇，也许是最古老的。这种单加氧酶催化了独特的三步反应（14？ - 甲基 - > 14？ - 醇 - > 14？-Aldehyde-> 14？ - 甲基化产物加甲酸），从最初自行车的固醇生物合成中的中间体中脱离了14米甲基，即胆固醇中的中间体，即胆固醇生物合成。 CYP51是真核病原体中的药物靶标，因为它催化的反应对于膜形成至关重要，因此该活性的丧失是致命的。在酵母和丝状真菌中，已将其作为药物靶标进行了广泛的研究，在该酵母和丝状真菌中，发现与CYP血红素铁结合的硫唑被发现是非常有效的药物。尚未对其他真核生物人类病原体进行详细研究，我们已经开始对锥虫和利什曼尼亚的CYP51进行详细的分析，包括它是否可以作为杀死这些生物体的药物目标，这些物体每年在“第三世界”中每年造成100万多人死亡，并且由于人类的迁移而成为一个严重的全球性问题，这是一个严重的全球问题，这是由于人类的迁移和生长的免疫变量而导致的。在本赠款的前两个资金周期中，我们对来自锥虫科的CYP51的详细研究得到了支持，在当前周期中，我们还表征了新型的化学支架，我们认为这是原生动物CYP51非常有效抑制剂的基础。这种竞争的更新应用程序包括三个特定目标。首先，是基于结构的原生动物CYP51选择性抑制剂的开发。在这里，我们将合成我们发现的三个原始支架的衍生物（基于Azole，吡啶和底物），并在四个测试系统中分析这些衍生物中最好的衍生物：原生动物本身，人类细胞，感染原生动物和小鼠模型的人类细胞。其次，我们将测试这些支架及其衍生物作为治疗白色念珠菌和曲霉（a）富马图斯和阿曲霉感染的潜在药物。这些真菌在人类中，尤其是免疫功能低下的患者，以及通过生物化学和生物物理学（包括其CYP51的X射线结构）进行表征的高度致病性，我们将确定哪些scoffids和衍生物对抗真菌药物设计最有效。第三，我们将比较来自三种不同生物王国（原生动物/真菌/人类）的CYP51的结构功能特征，以详细建立我们可以确定酶和抑制剂的特征的基础，这将导致病原体选择性药物和药物的合理设计，可有效CYP51-偏移的Azole抗性。总体而言，这些研究产生的结果将指导未来的药物开发方法，这将在全球健康中具有重要意义。