Conserved residues in the subunit interface of tau glutathione s-transferase affect catalytic and structural functions.
Conserved residues in the subunit interface of tau glutathione s-transferase affect catalytic and structural functions.
复制标题
tau 谷胱甘肽 S-转移酶亚基界面中的保守残基影响催化和结构功能。
DOI：
10.1111/j.1744-7909.2010.01005.x
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发表时间：
2011
影响因子：
11.4
通讯作者：
Hai
中科院分区：
文献类型：
--
作者：
Cai;Hai
tau类谷胱甘肽S-转移酶（GST）在作物和杂草的胁迫耐受性和除草剂的解毒中具有重要作用。小麦Tau GST（TaGSTU 4）的结构研究显示两个亚基相互作用：来自二聚体的另一个亚基的Tyr 93和Pro 65之间的氢键，和残基Glu 78与相对亚基中的Arg 95和Arg 99的侧链之间的两个盐桥。通过对酶活性、动力学参数和结构表征的研究，发现：（1）Tyr 93和Pro 65之间的氢键作用不是二聚化所必需的，但对酶的催化活性、热稳定性和对底物谷胱甘肽和1-氯-2，4-二硝基苯的亲和力有贡献;（ii）两个盐桥对蛋白质结构稳定性和催化作用起主要作用。本研究结果为合理设计选择性更强、环境友好的除草剂提供了结构和功能基础。
The tau class glutathione S-transferases (GSTs) have important roles in stress tolerance and the detoxification of herbicides in crops and weeds. Structural investigations of a wheat tau GST (TaGSTU4) show two subunit interactions: a hydrogen bond between the Tyr93 and Pro65 from another subunit of the dimer, and two salt bridges between residues Glu78 and side chains of Arg95 and Arg99 in the opposite subunit. By investigating enzyme activities, kinetic parameters and structural characterizations, this study showed the following results: (i) the hydrogen bond interaction between the Tyr93 and Pro65 was not essential for dimerization, but contributed to the enzyme's catalytic activity, thermal stability and affinity towards substrates glutathione and 1-chloro-2, 4-dinitrobenzene; and (ii) two salt bridges mainly contributed to the protein structure stability and catalysis. The results of this study form a structural and functional basis for rational design of more selective and environmentally friendly herbicides.