Muraki Norifumi, Seo Daisuke, Shiba Tomoo, Sakurai Takeshi, Kurisu Genji
Department of Life Sciences, University of Tokyo, Komaba, Tokyo 153-8902, Japan.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2008 Mar 1;64(Pt 3):186-9. doi: 10.1107/S1744309108003667. Epub 2008 Feb 23.
Ferredoxin-NAD(P)(+) reductase (FNR) is a key enzyme that catalyzes the photoreduction of NAD(P)(+) to generate NAD(P)H during the final step of the photosynthetic electron-transport chain. FNR from the green sulfur bacterium Chlorobium tepidum is a homodimeric enzyme with a molecular weight of 90 kDa; it shares a high level of amino-acid sequence identity to thioredoxin reductase rather than to conventional plant-type FNRs. In order to understand the structural basis of the ferredoxin-dependency of this unique photosynthetic FNR, C. tepidum FNR has been heterologously expressed, purified and crystallized in two forms. Form I crystals belong to space group C222(1) and contain one dimer in the asymmetric unit, while form II crystals belong to space group P4(1)22 or P4(3)22. Diffraction data were collected from a form I crystal to 2.4 A resolution on the synchrotron-radiation beamline NW12 at the Photon Factory.
铁氧化还原蛋白-NAD(P)(+)还原酶（FNR）是一种关键酶，在光合电子传递链的最后一步催化NAD(P)(+)的光还原以生成NAD(P)H。来自绿硫细菌嗜热栖热菌的FNR是一种分子量为90 kDa的同型二聚体酶；它与硫氧还蛋白还原酶具有高度的氨基酸序列同一性，而与传统的植物型FNR不同。为了了解这种独特光合FNR对铁氧化还原蛋白依赖性的结构基础，嗜热栖热菌FNR已通过异源表达、纯化并以两种形式结晶。I型晶体属于空间群C222(1)，在不对称单元中包含一个二聚体，而II型晶体属于空间群P4(1)22或P4(3)22。在光子工厂的同步辐射光束线NW12上，从I型晶体收集了分辨率为2.4 Å的衍射数据。
