MOLECULAR BIOLOGY OF ACETATE CONVERSION TO METHANE

复杂有机物转化为甲烷是一个重要的 是全球碳循环的一部分。 这个过程发生在各种各样的 厌氧环境;例如：（i）人的下肠， (ii)污水处理厂，以及（iii）湖泊、河流和 河流 因此，生物产甲烷影响环境和人类 健康在几个方面。 例如，甲烷是一种主要的“温室”气体。 另一方面，利用产甲烷过程来处理 工业和家庭废物，包括有毒化合物。 产甲烷 生物体是不同于真细菌的古细菌， 最基本的真核生物 因此，了解这些 不寻常的生物需要研究基本的细胞过程。 的 目前对产甲烷古细菌的了解主要是在 微生物学和生物化学水平;关于 基因表达的调控。 在这里，我们提出了一种分子遗传学 一种研究乙酸途径中基因表达的方法 转化为甲烷，其响应于生长而被严格调节 衬底 预计这些结果将扩展目前的观点， 包括基因表达的原则。 结果 也有望补充正在进行的生物化学研究的途径， 嗜热甲烷八叠球菌 长期目标是在体内利用 分子方法研究（i）转录的基本原理 在古细菌，和（ii）在酶的机制， 乙酸-甲烷途径。 本研究提出，与 平行研究，以表征突变体并开发转化 这将为这些长期目标奠定基础。

The conversion of complex organic matter to methane is an important component of the global carbon cycle. The process occurs in a variety of anaerobic environments; for example: (i) the lower intestine of humans, (ii) sewage treatment plants, and (iii) the sediments of lakes, streams and rivers. Thus, biological methanogenesis impacts the environment and human health in several ways. For example, methane is a major "greenhouse" gas. on the other hand, the process of methanogenesis is used to treat industrial and domestic wastes including toxic compounds. Methanogenic organisms are archaebacteria which are different from eubacteria and eukaryotes at the most elemental level. Thus, an understanding of these unusual organisms requires a study of fundamental cellular processes. The current understanding of methanogenic archaebacteria is largely at the level of microbiology and biochemistry; less is known concerning the regulation of gene expression. Here, we propose a molecular genetic approach to investigate gene expression in the pathway of acetate conversion to methane which is tightly regulated in response to the growth substrate. The results are expected to extend the current view of methanogenesis to include principles of gene expression. The results are also expected to compliment on-going biochemical studies on the pathway in Methanosarcina thermophila. The long-term goal is to utilize in vivo molecular approaches to study (i) fundamental principles of transcription in the archaebacteria, and (ii) the mechanism of enzymes in the acetate-to-methane pathway. The research proposed here, together with parallel research to characterize mutants and develop a transformation system, will lay the foundation for these long-term goals.