DNA glycosylases involved in interstrand crosslink repair and antibiotic self-resistance

DNA糖基化酶参与链间交联修复和抗生素自身抗性

• 批准号: 2341288
• 负责人: Brandt Eichman
• 金额: $ 130万
• 依托单位: Vanderbilt University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2341288&HistoricalAwards=false
• 关键词: DNA; glycosylases; involved; interstrand; crosslink; DNA; glycosylases; involved; interstrand; crosslink

DNA is chemically altered, or damaged, by its interaction with molecules found in the cell and in the environment. All organisms contain enzymes that repair damaged DNA to protect the integrity of the genetic information. This research project will determine how a newly discovered DNA repair enzyme found in bacteria works to repair damage created by specific toxins, which some bacteria produce as defense mechanisms. Because of their toxicity, these bacteria-derived toxins often have antimicrobial and antitumor properties, making them important in agriculture, industry, and medicine. The project will benefit society by providing 1) undergraduate and graduate students with hands-on experience in methods used to determine atomic structures of proteins that are important for discovery and innovation in biotechnology, 2) summer research opportunities to undergraduates of Fisk University, a nearby historically black college/university, 3) teaching and mentoring opportunities for all trainees, 4) exposure of high school students interested in STEM to biomedical research, and 5) community outreach. These activities are facilitated through a collaborative and inclusive training environment at the intersection of the College of Arts and Science and the School of Medicine at Vanderbilt University.Interstrand DNA crosslinks (ICLs) are among the most cytotoxic forms of DNA damage because they covalently tether the two DNA strands and therefore interfere with DNA replication and transcription. A new ICL repair pathway was recently discovered in both eukaryotes and prokaryotes, in which a DNA glycosylase liberates one of the crosslinked nucleobases from the DNA backbone. The bacterial ICL glycosylases belong to a family of uncharacterized proteins prevalent in antibiotic producers and pathogens. The PI’s laboratory discovered that E. coli YcaQ initiates an ICL repair pathway by unhooking chemically diverse ICLs, and characterized a related enzyme (AlkZ) that provides Streptomyces with self-resistance to the toxicity of one of its natural products, azinomycin B, by unhooking resulting azinomycin B-ICLs. The long-term goals of this project are to elucidate the ICL repair pathway in bacteria, to understand how microbes utilize DNA repair to protect against genotoxic natural products in nature and within the microbiome, and to discover new genotoxic agents with beneficial applications. The short-term goals are to understand the molecular basis for ICL unhooking by YcaQ and for the specificity of AlkZ-related enzymes for highly functionalized crosslinking and intercalating natural products, and to characterize the bioactivities of putative genotoxins. A multidisciplinary approach integrating structural biology, biochemistry, genetics, cell biology, and metabolomics will be employed to achieve these goals.This project is supported by the Genetic Mechanisms program in the Division of Molecular and Cellular Biosciences/Directorate for Biological Sciences and the Chemistry of Life Processes program in the Division of Chemistry/Directorate for Mathematical and Physical Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

DNA通过与细胞和环境中发现的分子相互作用而化学改变或损坏。所有生物体都含有修复损坏DNA的酶，以保护遗传信息的完整性。该研究项目将确定在细菌中发现的新发现的DNA修复酶如何修复特定毒素造成的损害，这些毒素有些细菌作为防御机制产生。由于它们的毒性，这些细菌衍生的毒素通常具有抗菌和抗肿瘤的特性，使其在同意，工业和医学方面重要。 The project will benefit society by providing 1) undergraduate and graduate students with hands-on experience in methods used to determine atomic structures of proteins that are important for discovery and innovation in biotechnology, 2) summer research opportunities to undergraduates of Fisk University, a near historically black college/university, 3) teaching and mentaling opportunities for all tr​​ainees, 4) exposure of high school students interested in STEM to biomedical research, and 5) community outreach.这些活动是通过艺术与科学学院和范德比尔特大学医学院交集的协作和包容性培训环境来准备的。InterstrandDNA交叉链接（ICL）是DNA损伤的最多的DNA损伤形式，因为它们共价绑扎了两个DNA链，因此与DNA的重复和转录相互作用。最近在真核生物和原核生物中都发现了一种新的ICL修复途径，其中DNA糖基酶从DNA骨架中解放了一个交联的核基质酶之一。 BIA糖基酶属于抗生素生产者和病原体中普遍的未表征蛋白质家族。 The PI’s laboratory discovered that E. coli YcaQ initiates an ICL repair pathway by unhooking Chemically diverse ICLs, and characterised a related enzyme (AlkZ) that provides Streptomyces with self-resistance to the toxicity of one of its natural products, azinomycin B, by unhooking resulting azinomycin B-ICLs.该项目的长期目标是阐明细菌中的ICL修复途径，以了解微生物如何利用DNA修复来防止自然界和微生物组中的遗传毒性天然产物，并发现具有有益应用的新遗传毒性剂。短期目标是了解YCAQ ICL解开的分子基础以及与ALKZ相关酶的特异性，用于高度功能化的交联和插入天然产物，并表征推测基因诺毒素的生物活性。将聘请一种多学科方法，该方法将结构生物学，生物化学，遗传学，细胞生物学和代谢组学纳入实现这些目标。法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准来评估的值得支持的。