Heterodisulfide Reductase in Methanosarcina acetivorans

甲烷的产生对许多与人类有关的问题至关重要， 全球变暖，废物处理，以及从生物材料中开发替代燃料。 地球上大部分甲烷是由产甲烷古菌通过已知的机制产生的 甲烷生成。甲烷生成的一个重要步骤是CoB-CoM异源双链的再生。 在甲烷产生时形成硫化物。负责CoB-CoM还原的酶复合物 被称为异二硫键还原酶（Hdr）。醋酸甲烷八叠球菌的基因组含有 编码可溶性HdrABC复合物和膜结合HdrDE复合物的ORF。是否 HdrABC和HdrDE具有专门的或完全冗余的功能，将通过创建 报告基因融合、靶基因缺失和嵌合Hdr复合物。的体外分析 嵌合酶复合物将用于鉴定对特异性和特异性结合重要的氨基酸残基， 选择性蛋白质：蛋白质相互作用。通过这些实验，探讨了产甲烷菌的作用机制。 esis和古细菌的电子传递系统将得到阐明，从而深入了解 能量产生和保存的过程对所有形式的生命都至关重要。

Methane production is critically important to a number of human-related problems including global warming, waste treatment, and the development of alternative fuels from biological materials. The bulk of methane on earth is produced by methanogenic archaea through the mechanism known as methanogenesis. An essential step in methanogenesis is regeneration of a CoB-CoM heterodi- sulfide formed upon methane production. The enzyme complex responsible for CoB-CoM reduction is known as heterodisulfide reductcase (Hdr). The genome of Methanosarcina acetivorans contains ORFs coding for a soluble HdrABC complex and a membrane-bound HdrDE complex. Whether HdrABC and HdrDE have specialized, or completely redundant functions will be tested by creatng reporter gene fusions, targeted gene deletions, and chimeric Hdr complexes. In vitro analysis of chimeric enzyme complexes will be used to identify amino acid residues important for specific and selective protein:protein interactions. Through these experiments, the mechanism of methanogen- esis and the archaeal electron transport system will be elucidated, thereby gaining insight into the processes of energy generation and conservation that are essential to all forms of life.