Cytochrome c oxidase (Heme aa3) from Paracoccus denitrificans:: Analysis of mutations in putative proton channels of subunit I
Cytochrome c oxidase (Heme aa3) from Paracoccus denitrificans:: Analysis of mutations in putative proton channels of subunit I
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DOI：
10.1023/a:1020515713103
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发表时间：
1998-02-01
影响因子：
3
通讯作者：
Richter, OMH
中科院分区：
文献类型：
--
作者：
Pfitzner, U;Odenwald, A;Richter, OMH
能量转导末端氧化酶（如反硝化副球菌的aa(3)细胞色素c氧化酶）的一个具有挑战性的特征是质子在细胞质膜上的易位，这与电子向氧的转移相结合。作为对酶性质进行更深入研究的先决条件，根据最近的三维结构测定选择的几个氨基酸残基通过位点定向诱变在副球菌酶的亚基I中进行了交换。用不同的方法分析了突变氧化酶的性质，以阐明它们是否参与质子通过两种不同途径的耦合和协调转移，要么是到氧还原位点，要么是通过酶从细胞质到质周侧。
One of the challenging features of energy-transducing terminal oxidases, like the aa(3) cytochrome c oxidase of Paracoccus denitrificans, is the translocation of protons across the cytoplasmic membrane, which is coupled to the transfer of electrons to oxygen. As a prerequisite for a more advanced examination of the enzymatic properties, several amino acid residues, selected on the basis of recent three-dimensional structure determinations, were exchanged in subunit I of the Paracoccus enzyme by site-directed mutagenesis. The properties of the mutated oxidases were analyzed by different methods to elucidate whether they are involved in the coupled and coordinated transfer of protons via two different pathways either to the site of oxygen reduction or through the enzyme from the cytoplasm to the periplasmic side.