Molecular dynamics and experimental investigation of H2 and O2 diffusion in [Fe]-hydrogenase
Molecular dynamics and experimental investigation of H2 and O2 diffusion in [Fe]-hydrogenase
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DOI：
10.1042/bst0330080
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发表时间：
2005-02-01
影响因子：
3.9
通讯作者：
King, P
中科院分区：
文献类型：
--
作者：
Cohen, J;Kim, K;King, P
[Fe]-氢化酶是一种高效的H-2催化剂，存在于生态和系统发育多样的微生物中，包括光合绿藻莱茵衣藻。虽然这些酶可以以多种形式发生，但H-2催化作用发生在位于活性位点的一个独特的[FeS]假基或h簇上。对于氢化酶的功能来说，重要的是周围的蛋白质结构如何促进底物-产物转移，并保护活性位点h簇免于失活。为了阐明蛋白质结构在[Fe]-氢化酶O-2失活中的作用，进行了实验和理论研究。采用分子动力学方法比较研究了O-2和H-2在巴氏梭菌Cpl （[Fe]-氢化酶I）中的扩散。我们的初步结果表明，H-2比O-2更容易和自由地扩散，这仅限于少数允许的途径进出活性位点。这些O-2通路位于保守的活性位点区域，实验表明在活性位点保护中具有重要作用。
The [Fe]-hydrogenase enzymes are highly efficient H-2 catalysts found in ecologically and phylogenetically diverse microorganisms, including the photosynthetic green alga, Chlomydomonas reinhardtii. Although these enzymes can occur in several forms, H-2 catalysis takes place at a unique [FeS] prosthetic group or H-cluster, located at the active site. Significant to the function of hydrogenases is how the surrounding protein structure facilitates substrate-product transfer, and protects the active site H-cluster from inactivation. To elucidate the role of protein structure in O-2 inactivation of [Fe]-hydrogenases, experimental and theoretical investigations have been performed. Molecular dynamics was used to comparatively investigate O-2 and H-2 diffusion in Cpl ([Fe]-hydrogenase I from Clostridium pasteurianum). our preliminary results suggest that H-2 diffuses more easily and freely than O-2, which is restricted to a small number of allowed pathways to and from the active site. These O-2 pathways are located in the conserved active site domain, shown experimentally to have an essential role in active site protection.