HypD is the scaffold protein for Fe-(CN)2CO cofactor assembly in [NiFe]-hydrogenase maturation.
HypD is the scaffold protein for Fe-(CN)2CO cofactor assembly in [NiFe]-hydrogenase maturation.
复制标题
HypD 是 [NiFe]-氢化酶成熟过程中 Fe-(CN)2CO 辅因子组装的支架蛋白
作者：
Stripp;Lindenstrauss;Braussemann;Herzberg;Sawers;Heberle
[NiFe]-氢酶在其催化的大亚基中结合NiFe-(CN)2CO辅因子。铁硫蛋白HypD和小辅助蛋白HypC在CO和CN-配体的生成中起着核心作用。红外光谱鉴定了厌氧分离的HypCD复合体上的特征，这些特征使人想起氢酶活性部位的特征，表明该复合体是辅因子的Fe-(CN)2CO部分在转移到氢酶大亚基之前的组装部位。在这里，我们报告在没有HypC的情况下分离的HypD在1956 cm-1、2072 cm-1和2092 cm-1处显示出红外带，分别属于CO、CN1和CN2，与HypCD复合体的红外带无法区分。不能分离具有CO或CN配基贡献的HypC。用EDTA处理HypD导致Fe、CO和CN-的伴随损失，而用H_2O_2氧化导致CO和CN-带分别正移35 cm~(-1)和20 cm~(-1)，这表明亚铁是双原子配体的直接连接位。对HypD氨基酸变异体的分析表明，半胱氨酸41、69和72是辅因子成熟所必需的。我们提出了一个精细的模型来研究Fe-(CN)2CO与HypD的连接以及HypC在[NiFe]-氢酶成熟中的作用。
[NiFe]-hydrogenases bind a NiFe–(CN)2CO cofactor in their catalytic large subunit. The iron–sulfur protein HypD and the small accessory protein HypC play a central role in the generation of the CO and CN–ligands. Infrared spectroscopy identified signatures on an anaerobically isolated HypCD complex that are reminiscent of those in the hydrogenase active site, suggesting that this complex is the assembly site of the Fe-(CN)2CO moiety of the cofactor prior to its transfer to the hydrogenase large subunit. Here, we report that HypD isolated in the absence of HypC shows infrared bands at 1956 cm–1, 2072 cm–1, and 2092 cm–1that can be assigned to CO, CN1, and CN2, respectively, and which are indistinguishable from those observed for the HypCD complex. HypC could not be isolated with CO or CN–ligand contribution. Treatment of HypD with EDTA led to the concomitant loss of Fe and the CO and CN–signatures, while oxidation by H2O2resulted in a positive shift of the CO and CN–bands by 35 cm–1and 20 cm–1, respectively, indicative of the ferrous iron as an immediate ligation site for the diatomic ligands. Analysis of HypD amino acid variants identified cysteines 41, 69, and 72 to be essential for maturation of the cofactor. We propose a refined model for the ligation of Fe-(CN)2CO to HypD and the role of HypC in [NiFe]-hydrogenase maturation.
登录
查看更多内容
影响因子：
2.9
作者：
BAGLEY, KA;VANGARDEREN, CJ;WOODRUFF, WH
通讯作者：
WOODRUFF, WH
大肠杆菌中催化活性氢化酶同工酶的成熟需要 hyp 操纵子基因产物
影响因子：
2.8
作者：
A. Jacobi;R. Rossmann;A. Böck
通讯作者：
A. Böck
芬顿氧化机制：生物相关底物与两种氧化中间体的反应性与羟基自由基的预测不同。
DOI：
10.1073/pnas.91.14.6604
发表时间：
1994
影响因子：
11.1
作者：
David A. Wink;Raymond W. Nims;Joseph E. Saavedra;W. E. Utermahlen;Peterc . Fords
通讯作者：
Peterc . Fords
阿拉伯糖途径调节基因 araC 的调节。
影响因子：
5.6
作者：
M. Casadaban
通讯作者：
M. Casadaban
影响因子：
4.8
作者：
Pierik, AJ;Roseboom, W;Albracht, SPJ
通讯作者：
Albracht, SPJ