MOLECULAR BIOLOGY OF ACETATE CONVERSION TO METHANE

将复杂的有机物转化为甲烷是一个重要的 全球碳循环的组成部分。这个过程发生在各种不同的 厌氧环境；例如：(I)人类的下肠， (Ii)污水处理厂；及。(Iii)湖泊、溪流及 河文。因此，生物产甲烷作用会影响环境和人类。 在几个方面的健康。例如，甲烷是一种主要的“温室”气体。 另一方面，产甲烷过程被用来治疗 工业和生活废物，包括有毒化合物。产甲烷 生物体是不同于真细菌的古细菌， 真核生物在最基本的水平上。因此，对这些的理解 不寻常的生物需要研究基本的细胞过程。这个 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，我们提出了一个分子遗传学 研究醋酸代谢途径中基因表达的方法 转化为甲烷，这是受到严格控制的，以应对增长 底物。预计这一结果将扩大目前对 甲烷化包括基因表达的原理。结果是 也预计将赞扬正在进行的关于该途径的生化研究 嗜热甲烷单胞菌。长期目标是在体内利用 分子方法研究(I)转录的基本原理 以及(Ii)古细菌中酶的作用机制。 醋酸盐转化为甲烷的途径。在这里提出的研究，连同 对突变体进行表征并开发转化的并行研究 系统，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.