Genome analysis in Methanosarcina mazei GÖ1: Mechanisms for the adaptation to different carbon- and energy sources

玛氏甲烷链霉菌属于古生界，能够将H2+CO2、甲醇、甲胺和乙酸盐转化为甲烷。根据碳源和能源的性质，有机体使用二氧化碳还原、甲基营养或产甲烷的分解途径。基于基因组序列，我们想要分析在特定途径中哪些基因是活跃的，这些基因是如何调控的，以及哪些调控网络可能参与其中。为了了解基因功能的动态本质，我们将阐明响应环境变化的全球表达模式。为此，将通过使用高密度DNA标准cDNA合成来进行全基因组表达谱分析，该合成来自于从不同底物上生长的细胞或从不同生长阶段收获的细胞获得的mRNA制备。在该项目的第二部分，将通过基因替换来创建Mazei女士的定义突变，以验证不同基因的功能。此外，使用Mazei女士的细胞裂解物进行的直接酶分析将有助于理解直接和间接影响甲烷生成的细胞过程。

The mesophilic organism Methanosarcina mazei belongs to the kingdom Archaea and is able to convert H2 + CO2, methanol, methylamines and acetate to methane. Depending on the nature of the carbon- and energy source the organism uses the CO2-reducing, the methylotrophic, or the aceticlastic pathway of methanogenesis. Based on the genomic sequence we would like to analyse which genes are active in a specific pathway, how these genes are regulated and which regulatory networks may be involved. To understand the dynamic nature of gene function the global expression pattern in response to environmental changes will be elucidated. For this purpose genome wide expression profiling will be performed by the use of high-density DNA standard cDNA synthesis from mRNA preparations obtained from cells grown on different substrates or from cells harvested at different growth phases. In the second part of the project defined mutants of Ms. mazei will be created by gene replacement to verify the function of distinct genes. In addition, direct enzymatic assays using cell lysates of Ms. mazei shall contribute to an understanding of cellular processes that directly and indirectly affect methanogenesis.