Nitrogenase-like Biosynthesis of (Bacterio)chlorophylls

光合作用对全球能量需求的捕获主要取决于（细菌）叶绿素的生物合成。此外，将大气中的二氮还原为氨对生态系统的燃料供应也至关重要。固氮酶复杂的生物化学过程对叶绿素和细菌叶绿素的形成起着重要作用。叶绿素和细菌叶绿素的生物合成都需要立体特异性还原原叶绿素D环的C17-C18双键，这可以由固氮酶样酶暗操作原叶绿素氧化还原酶（DPOR）催化。所有Bchl的生物合成需要第二种固氮酶样酶，称为叶绿酸氧化还原酶（COR），用于叶绿酸的C7-C8位置的立体特异性还原。在这里，我们想阐明COR，DPOR和固氮酶之间的催化差异。 我们打算解决的三维结构的底物结合的COR复合物。 此外，我们打算确定COR的人工小分子底物谱。这些结果将有助于进一步了解最近发现的固氮酶的CO还原能力，促进小烃的形成。

The photosynthetic capture of the global energy demand vitally depends on the biosynthesis of (bacterio)chlorophylls. Also the reduction of atmospheric dinitrogen to ammonia is essential for the fuelling of ecosystems. The sophisticated biochemistry of nitrogenase plays a fundamental role for the formation of chlorophylls and bacteriochlorophylls. The biosynthesis of both, chlorophylls and bacteriochlorophylls requires the stereospecific reduction of the C17-C18 double bond of ring D of protochlorophyllide which can be catalyzed by the nitrogenase-like enzyme dark-operative protochlorophyllide oxidoreductase (DPOR). The biosynthesis of all Bchls requires a second nitrogenase-like enzyme termed chlorophyllide oxidoreductase (COR) for the stereospecific reduction of the C7-C8 position of chlorophyllide. Here we want to elucidate the catalytic differences between COR, DPOR and nitrogenase. We intend to resolve the three-dimensional structure of the substrate-bound COR complex. Furthermore, we intend to identify the artificial small molecule substrate spectrum of COR. These results will help to further understand the recently discovered CO reducing capacity of nitrogenase which facilitates the formation of small hydrocarbons.