Generation of recombinant thiopeptides to target antimicrobial-resistant bacteria

生成重组硫肽以靶向抗菌素耐药细菌

• 批准号: 8798574
• 负责人: JAMES A WELLS
• 金额: $ 19.28万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-01 至 2017-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8798574
• 关键词: Adopted; Anabolism; Antibiotic Resistance; Antibiotics; Antimicrobial Resistance; Bacillus cereus; Bacillus subtilis; Bacteria; Bacterial Infections; Biological Assay; Biological Factors; Biological Models; Chemicals; Clinical; Clinical Treatment; Clostridium difficile; Collaborations; Development; Drug Formulations; Drug resistance; Exhibits; Generations; Genes; Genetic; Genetic Engineering; Goals; Gram-Positive Bacteria; Growth; Health; Infection; Intestines; Lead; Libraries; Life; Literature; Methods; Multi-Drug Resistance; Mutagenesis; Mutation; Nature; Peptides; Pharmaceutical Preparations; Phase; Phase II Clinical Trials; Plasmids; Point Mutation; Post-Translational Protein Processing; Prodrugs; Production; Public Health; Recombinants; Resistance; Ribosomal Proteins; Ribosomal RNA; Site; Solubility; Source; Structure; Structure-Activity Relationship; Testing; Therapeutic; Vancomycin resistant enterococcus; Work; analog; aqueous; bacterial resistance; clinically relevant; combat; combinatorial; design; drug development; drug discovery; drug resistant bacteria; flexibility; genetic manipulation; improved; in vivo; medical schools; methicillin resistant Staphylococcus aureus; mouse model; mutant; novel; pathogen; reconstitution; resistance mutation

DESCRIPTION (provided by applicant): The long-term goal of the proposed project is to develop a continuous and genetically encoded source of new antibiotics against drug-resistant bacterial pathogens by combining the power of recombinant DNA technology with the biosynthesis of natural product antibiotics. With the emergence of life-threatening drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), the need for new antibiotics is greater than ever. Yet, the development of new antibiotics has remained stagnant for nearly 50 years. A promising new class of natural products, called thiopeptides, inhibits the growth of these gram-positive bacteria at low nanomolar concentrations. Thiopeptides are exciting as potential antibiotics, because their site of action, the interface between ribosomal protein L11 and 23S rRNA, is distinct from all existing classes of antibiotics. Importantly, these natural products are derived from genetically encoded peptides, which allow for the generation of new thiopeptide analogs by simple mutagenesis. We have chosen to study the thiopeptide thiocillin as a model system, because unlike other thiopeptides, thiocillin is produced in the genetically tractable Bacillus cereus strain and is known to tolerate a variety of mutations. The immediate goal of the proposed project is to devise a method that will rapidly diversify and screen these thiopeptide natural products and thus accelerate discovery of new antibiotics. To achieve this goal, we will test the hypothesis that mutagenesis of thiocillin will provide a vast landscape of structural and chemical diversity capable of targeting antibiotic-resistant bacteria. The R21 phase of this project will focus on developing novel recombinant methods to rapidly generate large libraries of thiocillin natural products and to screen for new antibiotics. The R33 phase will develop a method to target potential resistance mutations and take promising hits through the drug development pipeline. The drug development phase will focus on increasing the solubility of thiocillin to develop an IV formulation for the treatment of systemic bacterial infections. If successful, the proposed project will have a significant impact on public health because the development of new antibiotic drugs is necessary to combat the rising problem of emerging drug resistance. Moreover, it will lay the groundwork for generating a new diverse class of natural products to screen for many other therapeutic applications.

描述（由申请人提供）：拟议项目的长期目标是通过将重组DNA技术的力量与天然产物抗生素的生物合成相结合，开发针对耐药细菌病原体的连续和遗传编码的新抗生素来源。随着耐甲氧西林金黄色葡萄球菌（MRSA）和耐万古霉素肠球菌（VRE）等危及生命的耐药细菌的出现，对新抗生素的需求比以往任何时候都大。然而，近50年来，新抗生素的开发一直停滞不前。一种很有前途的新型天然产物，称为硫肽，可以在低纳摩尔浓度下抑制这些革兰氏阳性细菌的生长。硫肽作为潜在的抗生素是令人兴奋的，因为它们的作用位点，核糖体蛋白L11和23S rRNA之间的界面，不同于所有现有的抗生素。重要的是，这些天然产物来源于基因编码的肽，这允许通过简单的诱变产生新的硫肽类似物。我们选择研究硫肽硫西林作为模型系统，因为与其他硫肽不同，硫西林是在遗传上易于处理的蜡样芽孢杆菌菌株中产生的，并且已知可以耐受多种突变。该项目的直接目标是设计一种方法，使这些硫肽天然产物迅速多样化和筛选，从而加速新抗生素的发现。为了实现这一目标，我们将测试一个假设，即硫西林诱变将提供一个巨大的结构和化学多样性的景观，能够靶向抗生素耐药细菌。该项目的R21阶段将侧重于开发新的重组方法，以快速生成大型硫西林天然产物文库并筛选新的抗生素。R33阶段将开发一种针对潜在耐药突变的方法，并通过药物开发管道获得有希望的成功。药物开发阶段将侧重于提高硫西林的溶解度，以开发用于治疗全身细菌感染的静脉制剂。如果成功，提议的项目