An investigation of the iron-sulphur proteins of benzene dioxygenase from Pseudomonas putida by electron-spin-resonance spectroscopy.
An investigation of the iron-sulphur proteins of benzene dioxygenase from Pseudomonas putida by electron-spin-resonance spectroscopy.
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通过电子自旋共振光谱研究恶臭假单胞菌苯二加氧酶的铁硫蛋白。
DOI：
10.1042/bj2170667
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
R. Cammack
中科院分区：
文献类型：
--
作者：
P. Geary;F. Saboowalla;D. Patil;R. Cammack
来自恶臭假单胞菌的苯双加氧酶由三种成分组成，即黄素蛋白（NADH：铁氧还蛋白氧化还原酶；Mr 81000）、中间电子转移蛋白或具有[2Fe-2S]簇的铁氧还蛋白（Mr 12000）和含有两个[2Fe-2S]铁硫簇的末端双加氧酶（Mr 215000），其需要两个额外的 Fe2+ 原子/分子用于加氧酶活性。铁氧还蛋白和双加氧酶产生 e.s.r.还原态信号具有菱形对称性，平均 g 值分别为 1.92 和 1.896。中点氧化还原电位通过 e.s.r. 测定。在pH 7.0 下分别滴定至-155 mV 和-112 mV。来自双加氧酶的信号显示出明显的 g 各向异性，并且与来自恶臭假单胞菌的 4-甲氧基苯甲酸单加氧酶以及呼吸和光合作用电子传递链的醌-细胞色素 c 区的 [2Fe-2S]“Rieske”蛋白最相似。
Benzene dioxygenase from Pseudomonas putida comprises three components, namely a flavoprotein (NADH:ferredoxin oxidoreductase; Mr 81000), an intermediate electron-transfer protein, or ferredoxin (Mr 12000) with a [2Fe-2S] cluster, and a terminal dioxygenase containing two [2Fe-2S] iron-sulphur clusters (Mr 215000), which requires two additional Fe2+ atoms/molecule for oxygenase activity. The ferredoxin and the dioxygenase give e.s.r. signals in the reduced state with rhombic symmetry and average g values of 1.92 and 1.896 respectively. The mid-point redox potentials were determined by e.s.r. titration at pH 7.0 to be -155 mV and -112 mV respectively. The signal from the dioxygenase shows pronounced g anisotropy and most closely resembles those of 4-methoxybenzoate mono-oxygenase from Pseudomonas putida and the [2Fe-2S] 'Rieske' proteins of the quinone-cytochrome c region of electron-transport chains of respiration and photosynthesis.