【摘要】 光合细菌 Chromatium vinosum可溶性氢酶经 5次柱层析 ( DE-2 3,TSK-DEAE( ) ,Ultragel Ac A-4 4 ,TSK-DEAE( ) ,Superdex TM75 )分离后被纯化 365倍 ,得率为 32 % ,其催化放氢的活性为 8.4μmol H2 /( min· mg prot) .氧化态可溶性氢酶在 4 5 K下 ,产生了 Ni( )的典型 EPR信号 ( gx,y,z=2 .37,2 .1 6,2 .0 1 6和 gx,y,z=2 .30 ,2 .2 3,2 .0 1 6) ;在 1 0 K下 ,没有出现膜结合态氢酶中存在的 [3Fe-4 S]簇特征 EPR信号 .可溶性氢酶被 H2 还原后 ,Ni( )的特征 EPR信号消失 ,同时出现一个 [4 Fe-4 S]簇的特征 EPR信号 ( gx,y,z=1 .88,1 .90 ,2 .0 4 5 ) .研究结果表明 ,C.vinosum可溶性氢酶在结构和功能上不同于膜结合态氢酶 ,是一种新的催化放氢的 Ni Fe-氢酶更多还原

【Abstract】 A soluble hydrogenase(SH) was purified from Chromatium vinosum by five step chromatography(DE 23, TSK DEAE(I), Ultragel AcA 44, TSK DEAE(Ⅱ), Superdex TM75) with a specific activity of 8.4 μmol H 2/(min·mg prot). The oxidized SH yield two Ni(Ⅲ) EPR(electron paramagnetic resonance) signals( g x,y,z = 2.37, 2.16, 2.016 and g x,y,z = 2.30, 2.23, 2.016 ) at 45 K which occurred in the other NiFe hydrogenases. However, no cluster EPR signal was obtained at 10 K. When the SH was reduced by H 2 (over night at 8 ℃), the Ni(Ⅲ) EPR signals disappeared, and an EPR signal from a reduced cluster appeared( g x,y,z = 1.88, 1.90, 2.045). The results show that the soluble hydrogenase from C.vinosum is a new NiFe hydrogenase which catalyzes H 2 production.更多还原