Shimomura Yoshimitsu, Sumiguchi-Agari Kazuko, Masui Ryoji, Kuramitsu Seiki, Fukuyama Keiichi
Department of Biology, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Acta Crystallogr D Biol Crystallogr. 2002 Aug;58(Pt 8):1365-7. doi: 10.1107/s090744490201003x. Epub 2002 Jul 20.
A probable quinone oxidoreductase (MW = 32.1 kDa) from Thermus thermophilus HB8 was overproduced in Escherichia coli and purified. Gel-filtration chromatography suggested the protein to be in a dimeric state. This protein enhanced the reduction activity of quinones by NADPH. It was crystallized in the absence and the presence of NADPH by the hanging-drop vapour-diffusion method. Both crystals were hexagonal, space group P6(1)22 or P6(5)22, with unit-cell parameters a = b = 77.6, c = 236.7 A for the apo form and a = b = 77.6, c = 235.9 A for the complex with NADPH. They diffract to better than 2.3 A resolution with synchrotron radiation. The asymmetric unit has one protein subunit (V(M) = 3.2 A(3) Da(-1) and V(sol) = 0.62 for the apo form), indicating that the twofold axis of the dimeric protein and the crystallographic twofold axis coincide.
嗜热栖热菌HB8中一种可能的醌氧化还原酶（分子量 = 32.1 kDa）在大肠杆菌中过量表达并进行了纯化。凝胶过滤色谱表明该蛋白质处于二聚体状态。这种蛋白质增强了NADPH对醌的还原活性。通过悬滴气相扩散法在有无NADPH的情况下使其结晶。两种晶体均为六方晶系，空间群为P6(1)22或P6(5)22，无辅基形式的晶胞参数为a = b = 77.6，c = 236.7 Å，与NADPH形成复合物的晶胞参数为a = b = 77.6，c = 235.9 Å。它们在同步辐射下的衍射分辨率优于2.3 Å。不对称单元有一个蛋白质亚基（无辅基形式的V(M) = 3.2 Å(3) Da(-1)且V(sol) = 0.62），这表明二聚体蛋白质的二重轴与晶体学二重轴重合。
