Stoichiometry of ATP hydrolysis and chlorophyllide formation of dark-operative protochlorophyllide oxidoreductase from Rhodobacter capsulatus
Stoichiometry of ATP hydrolysis and chlorophyllide formation of dark-operative protochlorophyllide oxidoreductase from Rhodobacter capsulatus
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荚膜红杆菌暗操作原叶绿素氧化还原酶的 ATP 水解和叶绿素内酯形成的化学计量
DOI：
10.1016/j.bbrc.2016.01.070
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发表时间：
2016
影响因子：
3.1
通讯作者：
Y.
中科院分区：
文献类型：
--
作者：
Nomata;J.;Terauchi;K. and Fujita;Y.
暗操作原叶绿素 (Pchlide) 氧化还原酶 (DPOR) 是一种固氮酶样酶，在细菌叶绿素生物合成中催化 Pchlide 的 C17 = C18 双键还原形成叶绿素 (Chlide)。 DPOR 由 ATP 依赖性还原酶成分 L-蛋白（BchL 二聚体）和催化成分 NB-蛋白（BchN-BchB 异四聚体）组成。 L-蛋白将电子转移到 NB-蛋白以还原 Pchlide，这与 ATP 水解相结合。在这里，我们确定了 ATP 水解和 DPOR 氯化物形成的化学计量。 ATP 与 Chlide 的最小比率 (ATP/2e–) 为 4，与固氮酶的比率一致。该比率随着L-蛋白与NB-蛋白的摩尔比的增加而增加。该谱与固氮酶的谱不同。这些结果表明 DPOR 具有特定的内在特性，同时保留了与固氮酶共有的共同特征。
Dark-operative protochlorophyllide (Pchlide) oxidoreductase (DPOR) is a nitrogenase-like enzyme catalyzing a reduction of the C17 = C18 double bond of Pchlide to form chlorophyllidea(Chlide) in bacteriochlorophyll biosynthesis. DPOR consists of an ATP-dependent reductase component, L-protein (a BchL dimer), and a catalytic component, NB-protein (a BchN–BchB heterotetramer). The L-protein transfers electrons to the NB-protein to reduce Pchlide, which is coupled with ATP hydrolysis. Here we determined the stoichiometry of ATP hydrolysis and the Chlide formation of DPOR. The minimal ratio of ATP to Chlide (ATP/2e–) was 4, which coincides with that of nitrogenase. The ratio increases with increasing molar ratio of L-protein to NB-protein. This profile differs from that of nitrogenase. These results suggest that DPOR has a specific intrinsic property, while retaining the common features shared with nitrogenase.