PDF(Pubmed)
Abstract：
Molybdenum- or tungsten-dependent formate dehydrogenases have emerged as significant catalysts for the chemical reduction of CO2 to formate, with biotechnological applications envisaged in climate-change mitigation. The role of Met405 in the active site of Desulfovibrio vulgaris formate dehydrogenase AB (DvFdhAB) has remained elusive. However, its proximity to the metal site and the conformational change that it undergoes between the resting and active forms suggests a functional role. In this work, the M405S variant was engineered, which allowed the active-site geometry in the absence of methionine Sδ interactions with the metal site to be revealed and the role of Met405 in catalysis to be probed. This variant displayed reduced activity in both formate oxidation and CO2 reduction, together with an increased sensitivity to oxygen inactivation.
摘要：
依赖钼或钨的甲酸脱氢酶已成为将CO2化学还原为甲酸的重要催化剂，在减缓气候变化方面设想的生物技术应用。Met405在寻常脱硫弧菌甲酸脱氢酶AB（DvFdhAB）的活性位点中的作用仍然难以捉摸。然而,它靠近金属位点以及它在静止和活性形式之间经历的构象变化表明了功能作用。在这项工作中,M405S变体被设计，这使得在没有甲硫氨酸Sδ与金属位点相互作用的情况下，活性位点的几何形状得以揭示，并且Met405在催化中的作用得以探测。该变体在甲酸氧化和CO2还原中都显示出降低的活性，以及对氧失活的敏感性增加。
