Elucidation of the binding of the C1 carrier, tetrahydromethanopterin, and its derivatives, to enzymes involved in the energy metabolism pathway of methanogenic archaea

在产甲烷和硫酸盐还原的古菌中，四氢甲烷蝶呤(H4MPT)在甲酰和甲基氧化水平之间扮演着一个C1载体的角色。它是许多酶反应中的辅酶，在结构上类似于四氢叶酸(H4F)--大多数其他生物中的C1载体。本项目旨在研究四氢甲烷蝶呤及其衍生物与产甲烷古菌能量代谢途径中涉及的酶的结合。主要的重点将是用X射线结晶学解决酶-辅酶络合物的结构。这些结构有望对辅酶的结合位置提供重要的见解，从而了解许多对产甲烷至关重要的酶反应的机制。选择了产甲烷途径中的三种酶--亚甲基-H4MPT环水解酶、甲酰甲烷呋喃：H4MPT甲酰转移酶和甲基-H4MPT：辅酶M甲基转移酶。此外，该项目旨在开发一种结合到这些酶上的辅酶的荧光分析方法。文中分别给出了目标、方法、WIRK计划和时间表的详细描述。

In methanogenic and sulfate-reducing archaea tetrahydromethanopterin (H4MPT) acts as a C1 carrier between formyl and methyl oxidation levels. It is a coenzyme in many enzymatic reactions and is structurally analogous to tetrahydrofolate (h4F) - the C1 carrier in most other organisms. This project aims to study the binding of tetrahydromethanopterin, and its derivatives, to enzymes involved in the energy metabolism pathway of methanogenic archaea. The major emphasis will be towards solving the structure of the enzyme-coenzyme complexis by X-ray crystallography. These structures are expected to give important insight into the binding sites of the coenzyme and thus, into the mechanism of many enzymatic reactions critical to methanogenesis. Three enzymes - the methenly-H4MPT cyclohydrolase, the formylmethanofuran:H4MPT formyltransferase and the methyl-H4MPT:coenzyme M methyltransferase - from the methanogenic pathway have been chosen for this study. Additionally, the project aims to develop a fluorimetric assay for coenzyme bindung to these enzymes. Detailed description of aims, methods, wirk plan and time schedule are given separately.