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Published on: November 3, 2018
Purification, crystallization and preliminary X-ray diffraction analysis of ArsH from Synechocystis sp. strain PCC
Xiao Zhang1, Xi-Mei Xue1, Yu Yan1
1Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021, People's Republic of China.
Abstract:
ArsH is an NADPH-dependent flavin mononucleotide reductase and is frequently encoded as part of an ars operon. The function of the arsH gene remains to be characterized. Crystallization and structural studies may contribute to elucidating the specific biological function of ArsH associated with arsenic resistance. ArsH from Synechocystis sp. strain PCC 6803 was overproduced, purified and crystallized. Crystals were obtained by the sitting-drop vapour-diffusion method. Diffraction data were collected and processed to a resolution of 1.6 Å. The crystals belonged to the tetragonal space group I4122, with unit-cell parameters a = b = 127.94, c = 65.86 Å and one molecule in the asymmetric unit. Size-exclusion chromatography and molecular-replacement results showed that the ArsH formed a tetramer. Further structural analysis and comparison with ArsH from Sinorhizobium meliloti will provide information about the oligomerization of ArsH.
