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利用分子力学和量子力学方法研究人类谷胱甘肽S-转移酶M1a-1a催化谷胱甘肽对1-氯-2,4二硝基苯(CDNB)的亲核芳香取代反应的细节.所获得的反应路径显示反应仅经历一个过渡态且能垒很低.电荷布居分析证明电子从谷胱甘肽基团流向二硝基苯,验证了反应的发生.计算结果表明活性位点3个残基(Tyr6,His107和Tyr115)参与了催化反应,尤其是His107,它在反应后期通过与产物形成氢键从而加速了Cl的释放.结果支持了Patskovsky等人提出的机理,并有助于其他谷胱甘肽S-转移酶的研究.
Molecular and quantum mechanistic methods were used to study the nucleophilic aromatic substitution reaction of glutathione S-transferase M1a-1a catalyzed by glutathione on 1-chloro-2,4-dinitrobenzene (CDNB). The obtained reaction pathway showed that the reaction only experienced a transition state and the energy barrier was very low. The charge population analysis showed that electrons flowed from the glutathione group to dinitrobenzene and the reaction was confirmed. The calculated results showed that 3 active sites Residues (Tyr6, His107 and Tyr115) participate in a catalytic reaction, especially His 107, which accelerates the release of Cl by hydrogen bonding with the product at the end of the reaction.The results support the mechanism proposed by Patskovsky et al and contribute to other Study on glutathione S-transferase.