Elucidating how CRISPR-Cas Modulates the Spread of S. aureus Pathogenicity Islands

阐明 CRISPR-Cas 如何调节金黄色葡萄球菌致病岛的传播

• 批准号: 10315193
• 负责人: Dalton Van Banh
• 金额: $ 5.1万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-06 至 2025-08-05
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10315193
• 关键词: Affect; Antibiotic Resistance; Antibiotics; Antimicrobial Resistance; Automobile Driving; Bacteria; Bacterial Chromosomes; Bacterial Infections; Bacteriophages; Biological; Biological Assay; Cells; Clustered Regularly Interspaced Short Palindromic Repeats; Community-Acquired Infections; Complex; Data; Development; Disease; Doctor of Philosophy; Elements; Enterotoxins; Evolution; Excision; Fellowship; Foundations; GTP-Binding Protein alpha Subunits, Gs; Genes; Genetic; Genetic Transcription; Genome; Genus staphylococcus; Goals; Horizontal Gene Transfer; Immunity; Immunization; Infection; Invaded; Laboratories; Larva; Life Cycle Stages; Measures; Mediating; Medical; Mobile Genetic Elements; Modeling; Molecular; Molecular Genetics; Multi-Drug Resistance; Multiple Bacterial Drug Resistance; Nosocomial Infections; Pathogenesis; Pathogenicity Island; Physicians; Plasmids; Population; Principal Investigator; RNA; Research; Ribonucleases; Scientist; Staphylococcus aureus; Superantigens; System; Testing; Tetracycline Resistance; Therapeutic; Toxic Shock Syndrome; Toxin; Training; Virulence; Virulence Factors; Virulent; Work; adaptive immunity; antimicrobial; base; career; colonization resistance; commensal microbes; design; experimental study; genetic approach; global health; in vivo; insight; multi-drug resistant pathogen; mutant; novel therapeutic intervention; nuclease; particle; pathogen; prevent; programs; reproductive; resistance gene; staphylococcal enterotoxin; targeted treatment; transmission process

PROJECT SUMMARY/ABSTRACT Staphylococcus aureus is a major cause of both community-acquired and nosocomial infections, which have become increasingly challenging to treat due to the widespread evolution of antimicrobial resistance. There is a critical need for the development of alternative therapeutic approaches against multidrug-resistant bacteria that also spare the protective commensal microbiota, which often provide colonization resistance against pathogens. Bacterial disease is driven by S. aureus toxins and other virulence factors, which are mainly encoded by mobile genetic elements (MGEs). In particular, numerous enterotoxins and the superantigen toxin causing Toxic Shock Syndrome are all carried by a class of MGEs called the S. aureus Pathogenicity Islands (SaPIs), which spread between bacteria by hijacking the reproductive machinery of bacteriophages. Staphylococci also possess CRISPR-Cas systems, which provide adaptive immunity by blocking invading MGEs like phages and plasmids. In this proposal, building upon preliminary data, I will test the central hypothesis that CRISPR-Cas systems also prevent the transmission of SaPI elements and their associated virulence genes. In Aim 1, I will define the complex tripartite interplay between staphylococcal CRISPR systems, SaPIs, and their helper phages using various molecular and genetic approaches. In Aim 2, I will investigate the mechanisms by which SaPIs manage to overcome CRISPR-mediated restriction and disseminate throughout bacterial populations. I anticipate that these studies will elucidate both the molecular basis and biological consequences for CRISPR-SaPI interactions. In Aim 3, I will evaluate whether CRISPR can be used to selectively kill SaPI-harboring S. aureus and establish a proof-of-concept for CRISPR-based antimicrobials directed against virulence-encoding MGEs. The proposed experiments will contribute to the long-term goal of designing alternative therapeutic approaches in an effort to overcome the shortcomings of antibiotics in treating multidrug-resistant infections. This fellowship will support my training in the Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, including my doctoral work in the laboratory of Dr. Luciano Marraffini at Rockefeller and the remainder of my medical training at Weill Cornell. The training plan outlined in this fellowship project is designed to optimally prepare me for a research career as an independent principal investigator and physician-scientist.

项目总结/摘要 金黄色葡萄球菌是社区获得性和医院感染的主要原因， 由于抗菌素耐药性的广泛演变，治疗变得越来越具有挑战性。有一个 迫切需要开发针对多重耐药细菌的替代治疗方法， 保护性的肠道微生物群也不受影响，因为它们通常提供对病原体的定殖抗性。 细菌性疾病是由S.金黄色葡萄球菌毒素和其他毒力因子，其主要由移动的 遗传因子（MGE）。特别是，许多肠毒素和超抗原毒素导致中毒性休克 综合征都是由一类称为S的MGE携带的。金黄色葡萄球菌致病性岛（SaPI）， 通过劫持噬菌体的繁殖机制来改变细菌之间的关系。葡萄球菌还具有 CRISPR-Cas系统，通过阻断入侵的MGE如质粒和质粒来提供适应性免疫。 在本提案中，基于初步数据，我将测试CRISPR-Cas系统也 防止SaPI元件及其相关毒力基因的传播。在目标1中，我将定义 葡萄球菌CRISPR系统、SaPI及其辅助分子之间复杂的三方相互作用， 各种分子和遗传学方法。在目标2中，我将研究SaPI管理的机制 克服CRISPR介导的限制并在整个细菌群体中传播。我预计 这些研究将阐明CRISPR-SaPI相互作用的分子基础和生物学后果。 在目标3中，我将评估CRISPR是否可以用于选择性地杀死携带SaPI的S。金黄色葡萄球菌和建立 针对编码毒力的MGE的基于CRISPR的抗菌剂的概念验证。拟议 实验将有助于设计替代治疗方法的长期目标， 克服了抗生素治疗多重耐药感染的不足。该奖学金将支持 我在威尔康奈尔/洛克菲勒/斯隆凯特琳三机构MD-PhD计划的培训，包括我的 我在洛克菲勒的卢西亚诺·马拉菲尼博士的实验室里完成了博士学位， 威尔康奈尔大学这个奖学金项目中概述的培训计划旨在为我做好最佳准备， 作为独立的首席研究员和医生科学家的研究生涯。