中文摘要：

那熨的从 recombinant Escherichia 关口 i 的包括身体显示出的硫加氧酸 reductase (SOR ) 的 refolding 上的以前的学习对从 Acidianus ambivalens 的 SOR 的活动批评。在这研究，酶的试金显示出那 2,2 ′-Dipyridyl， Tiron 和 8-hydroxyquinoline，它为螫合剂 ferrous 或铁的离子是特定的，强烈从 A 禁止了 SOR 的活动。tengchongensis，建议那个铁原子为 SOR 是必要的活动。从染色体数据库的几个机能上地识别的 SOR 和象 SOR一样序列的排列揭示了一个保存的、通常认为的铁绑定主题， H ⁸⁶-X₃-H⁹⁰-X _n -E¹¹⁴-X _n -E¹²⁹(根据 Acidianus tengchongensis SOR 顺序数)。SOR 的三异种被 H ₈₆, H ₉₀ 和 E ₁₂₉ 的指导地点的傻瓜发育不全在这研究产生进本氨基丙酸或丙氨酸残余。圆形的二色性光谱决心显示没有变异的 SOR 的第二等的结构的变化， H ⁸⁶ F， H ⁹⁰ F 和 E ¹²⁹ A，而是所有异种是完全不活跃的。通过铁内容的决心，我们发现那 SOR H ⁸⁶ F ， H ⁹⁰ F 和 E ¹²⁹一个完全或部分失去的熨斗 C ³¹ S ， C ¹⁰¹ S ，并且 C ¹⁰⁴ S (在以前的研究产生了)。这结果显示了那 H ⁸⁶, H ⁹⁰ 和 E ¹²⁹ 然而并非 C ³¹, C ¹⁰¹, ， C ¹⁰⁴ 涉及绑定熨原子。基于这和以前的研究，保存主题， C ³¹-X _n -C¹⁰¹-X₂-C¹⁰⁴ 和 H ⁸⁶-X₃-H⁹⁰-X₂₃-E¹¹⁴-X₁₄-(E/D)¹²⁹, 是，这被建议分别地为硫和分子的氧绑定和激活。这二个保存主题是为 SOR 活动的必需元素。

英文摘要：

Previous study on refolding of sulfur oxygenase reductase （SOR） inclusion bodies from recombinant Escherichia coil showed that iron was critical to the activity of the SOR from Acidianus ambivalens. In this study, enzymatic assays showed that 2,2＇-Dipyridyl, Tiron and 8-hydroxyquinoline, which are specific for chelating ferrous or ferric ions, strongly inhibited the activity of SOR from A. tengchongensis, suggesting that iron atom is essential for SOR activity. Alignment of several functionally identified SORs and SOR-like sequences from genome database revealed a conserved, putative iron binding motif, H^86-X3-H^90-Xn-E^114-Xn-E^129 （numbering according to the Acidianus tengchongensis SOR sequence）. Three mutants of SOR were generated by site-directed mutagenesis of H^86, H^90 and E^129 into phenylalanine or alanine residue in this study. Circular dichroism spectrum determination indicated that there was no change of the secondary structures of mutant SORs, H^86F, H^90F and E^129A, but all mutants were completely inactive. Through determination of iron contents we found that SOR mutants of H^86F, H^90F and E^129A completely or partially lost iron, while mutants of C^31S, C^101S, and C^104S （generated in a previous study） did not. This result indicated that H^86, H^90 and E^129 but not C^31, C^101, and C^104 were involved in binding to iron atom. Based on this and previous studies, it is proposed that the conserved motifs, C31-Xn-C^101-X2-C^104 and H^86-X3-H^90-X23-E^114-X14-（E/D）^129, are respectively for sulfur and molecular oxygen binding and activation. These two conserved motifs are essential elements for the SOR activity.