Methods for nitrogenase-like dark operative protochlorophyllide oxidoreductase.
Methods for nitrogenase-like dark operative protochlorophyllide oxidoreductase.
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固氮酶样暗操作原叶绿素内酯氧化还原酶的方法
DOI：
10.1007/978-1-61779-194-9_9
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发表时间：
2011
影响因子：
--
通讯作者：
Bröcker
中科院分区：
文献类型：
--
作者：
Bröcker
固氮酶样暗操作原叶绿素氧化还原酶(DPOR)参与裸子植物、蕨类、藻类和光合细菌中叶绿素和细菌叶绿素的生物合成。在原叶绿素(Pchlide)还原过程中，DPOR的同源二聚体亚基ChlL2将电子转移到相应的异四聚体催化亚基(ChlN/ChlB)2上。虽然DPOR与固氮酶系统有显著的氨基酸序列同源性，但只有DPOR的初始催化步骤类似于固氮酶催化。对海洋原氯球菌DPOR的研究表明，ChlL2亚复合体作为一种依赖于ATP的开关蛋白，触发了ChlL2与(ChlN/ChlB)2的瞬时相互作用。这种动态的亚基相互作用负责将单个电子从ChlL2的[4Fe-4S]簇转移到位于(ChlN/ChlB)2上的第二个[4Fe-4S]簇。然而，DPOR的第二部分催化与固氮酶催化无关，因为没有使用含钼的辅因子或P-簇的等价物。相反，两个连续的电子转移步骤是通过(ChlN/ChlB)2的[4Fe-4S]簇介导的，导致底物分子Pchlide的共轭环系还原(图5.1a和5.2)。
Nitrogenase-like dark operative protochlorophyllide oxidoreductase (DPOR) is involved in the biosynthesis of chlorophylls and bacteriochlorophylls in gymnosperms, ferns, algae, and photosynthetic bacteria. During protochlorophyllide (Pchlide) reduction, the homodimeric subunit ChlL2of DPOR transfers electrons on the corresponding heterotetrameric catalytic subunit (ChlN/ChlB)2. Although DPOR shares significant amino acid sequence homology to the nitrogenase system, only the initial catalytic steps of DPOR resemble nitrogenase catalysis. Investigation of the cyanobacterial DPOR fromProchlorococcus marinusindicated that subcomplex ChlL2is functioning as an ATP-dependent switch protein, triggering the transient interaction of ChlL2and (ChlN/ChlB)2. This dynamic subunit interplay is responsible for the transfer of a single electron from the [4Fe–4S] cluster of ChlL2onto a second [4Fe–4S] cluster located on (ChlN/ChlB)2. However, the second part of DPOR catalysis is unrelated to nitrogenase catalysis, since no molybdenum-containing cofactor or a P-cluster equivalent is employed. Instead, two consecutive electron transfer steps are mediated via the [4Fe–4S] cluster of (ChlN/ChlB)2, resulting in the reduction of the conjugated ring system of the substrate molecule Pchlide (Figs. 5.1aand5.2).
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影响因子：
4.8
作者：
Broecker, Markus J.;Waetzlich, Denise;Jahn, Dieter
通讯作者：
Jahn, Dieter
影响因子：
4.8
作者：
Broecker, Markus J.;Waetzlich, Denise;Jahn, Dieter
通讯作者：
Jahn, Dieter
影响因子：
4.8
作者：
Broecker, Markus J.;Virus, Simone;Moser, Juergen
通讯作者：
Moser, Juergen
原叶绿素：一种新型光敏剂，用于光动力灭活革兰氏阳性和革兰氏阴性细菌。
影响因子：
2.1
作者：
J. Walther;M. Bröcker;Denise Wätzlich;M. Nimtz;M. Rohde;D. Jahn;J. Moser
通讯作者：
J. Moser