Analysis of Oxygen Adaptation in Methanogenic Archaea

描述（由申请人提供）：拟议研究的长期目标是鉴定和表征厌氧产甲烷菌中与氧适应相关的新型蛋白质，以便为氧解毒酶的功能和进化提供基础。这项调查是重要的，因为在所有活细胞中的一般防御机制的氧化物质的解毒的相关性，而且在病原体对宿主防御细胞产生的氧化爆发的反应。此外，甲烷的产生与全球变暖的问题有关，而且还有很多关于红球藻的生理学、生物化学和遗传学的知识需要了解。本研究计划的具体目标是：a）利用醋酸甲烷八叠球菌全基因组微阵列鉴定细胞暴露于氧气、超氧化物和过氧化氢期间上调的基因，B）对先前鉴定的编码可能的氧化应激蛋白（包括超氧化物还原酶和红氧还蛋白）的基因簇进行转录分析和表达谱分析：氧氧化还原酶（ROO），c）过表达和纯化来自M. acetivorans，以验证其在该生物体的生理学背景下的催化特性。

DESCRIPTION (provided by applicant): The long term objectives of the proposed research are to identify and characterize novel proteins associated with oxygen adaptation in anaerobic methane-producing Archaea in order to provide a foundation of the function and evolution of oxygen detoxification enzymes. This investigation is important due to the relevance of detoxification of oxidative species as a general defense mechanism in all living cells, but also in the response of pathogens to oxidative burst produced by host defense cells. In addition, methane production is relevant to the problems of global warming and there is still much to learn about the physiology, biochemistry, and genetics of Archaea. The specific aims of this research proposal are: a) utilize a Methanosarcina acetivorans complete genome microarray to identify genes up-regulated during exposure of cells to oxygen, superoxide, and hydrogen peroxide, b) conduct transcriptional analysis and expression profiling of a previously identified gene cluster encoding probable oxidative stress proteins, including a superoxide reductase and rubredoxin: oxygen oxidoreductase (ROO), c) overexpress and purify the putative ROO from M. acetivorans to verify its catalytic properties in the context of the physiology of this organism.