沼泽红假单胞菌砷(Ⅲ)S-腺苷甲基转移酶的初步晶体学分析

Crystallization and preliminary X-ray crystallographic analysis of the arsenic(Ⅲ) S-adenosylmethionine methyltransferase from rhodopseudanonas palustris

含砷化合物有高毒性,一直是全球性的公共卫生难题。许多微生物能利用S-腺苷甲基转移酶(ArsM酶)催化有剧毒的无机As(Ⅲ)发生甲基化而解毒。为揭示酶促反应的真实机制,我们将来源于沼泽红假单胞菌(Rhodopseudanonas palustris)的ArsM酶(RpArsM)重组表达、纯化及结晶。在上海光源BL17U1线站收集蛋白晶体衍射数据,初步晶体学分析表明,RpArsM酶的晶体属于P212121空间群,晶胞参数分别是a=45.92,b=66.58,c=147.82,α=β=γ=90°,衍射分辨率达2.0。

For the ubiquitous distribution and high toxicity in the ecosystem,arsenic contaminants have been a world-wide public health problem for decades.The enzyme ArsM has the ability of methylating the inorganic arsenite.To study mechanism of the process,the recombinant ArsM from Rhodopseudanonas palustris（RpArsM） was expressed,purified and crystallized.The RpArsM crystals were examined by X-ray crystallography on Beamline BL17U1 at Shanghai Synchrotron Radiation Facility,and the diffraction data were processed to a resolution of 2.0.The results show that the RpArsM crystals are of the P212121space group,with unit-cell parameters a=45.92,b=66.58,c=147.82 and α=β=γ=90°.