Redox Photochemistry in Genomes of Microorganisms

微生物基因组中的氧化还原光化学

• 批准号: 1808475
• 负责人: Cynthia Burrows
• 金额: $ 52.5万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1808475&HistoricalAwards=false
• 关键词: Redox; Photochemistry; Genomes; Microorganisms

The Chemistry of Life Processes Program in the Division of Chemistry is awarding funding to Dr. Cynthia Burrows at the University of Utah. Her research team plans to investigate how the genomes of microorganisms adapt to environmental stress. Many species of plants, algae and bacteria have adapted to live under extreme conditions of heat, salt, drought or intense UV light, all of which place chemical stress on the cell's DNA. Other organisms, such as the coral symbiont zooxanthellae, a close cousin of algae, have not adapted to stress, and rising ocean temperatures are leading to coral 'bleaching' due to loss of their algae, a food source for the coral. Research supported by this grant investigates the hypothesis that sequences of DNA that can fold into a motif termed "G-quadruplex" may help the organism respond to oxidative stress caused by an increase in temperature and increased photosynthesis. Students involved in this work are to learn how the chemistry of the environment influences the chemistry of the cell at the level of the organism's genetic code. In addition, the PI is developing a series of lectures, "Beyond Watson and Crick," that communicate the importance of changes in the DNA to life processes.To address the question of why certain microorganisms, notably algae and thermophilic bacteria, have dense potential G-quadruplex sequences (PQS) in their genomes, a reporter plasmid assay is to be developed in the model algal organism Chlamydomonas. Synthetically altered DNA sequences is to be inserted into promoter sequences of a reporter gene, and gene expression will be monitored as a function of oxidative stress. In addition, the PQS density in Thermus bacteria is to be investigated. The sites of oxidative damage are to be mapped onto the promoter regions and PQS sites to discover correlations between G-quadruplex sequences, regulation of oxidative damage, and adaptive responses to environmental stress. These studies help define the circumstances under which chemically-modified bases in DNA, such as 8-oxoguanine, serve as epigenetic markers.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.

化学系的生命过程化学项目正在向犹他大学的辛西娅·布伦斯博士提供资金。她的研究团队计划调查微生物基因组如何适应环境压力。许多种类的植物、藻类和细菌已经适应了在高温、盐、干旱或强烈紫外光的极端条件下生活，所有这些都给细胞的DNA带来了化学压力。其他生物，如珊瑚共生体动物黄藻，藻类的近亲，还没有适应压力，而不断上升的海洋温度正在导致珊瑚的白化，因为它们的藻类失去了珊瑚的食物来源。由这笔拨款支持的研究调查了一种假说，即可以折叠成被称为G-四链体的基序的DNA序列可能有助于有机体对温度升高和光合作用增强引起的氧化应激做出反应。参与这项工作的学生将学习环境的化学如何在有机体的遗传密码水平上影响细胞的化学。此外，PI正在开发一系列讲座，“超越沃森和克里克”，传达DNA变化对生命过程的重要性。为了解决为什么某些微生物，特别是藻类和嗜热菌，在它们的基因组中具有密集的潜在G-四链序列(PQs)的问题，将在藻类生物衣藻中开发一种报告质粒法。人工改变的DNA序列将被插入到报告基因的启动子序列中，基因表达将作为氧化应激的函数进行监测。此外，还对热菌中PQS的密度进行了研究。氧化损伤的位点将被定位在启动子区域和PQS位点上，以发现G-四链序列、氧化损伤的调节和对环境胁迫的适应性反应之间的相关性。这些研究有助于确定DNA中化学修饰的碱基，如8-氧鸟嘌呤，在什么情况下充当表观遗传标记。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。