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化学学报
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化学学报 ›› 2010, Vol. 68 ›› Issue (21): 2186-2190. 上一篇    下一篇

研究论文

2-磷酸甘油酸脱水反应机理的理论研究

曲威，王长生*   

  1. (辽宁师范大学化学化工学院 大连 116029)
  • 投稿日期:2010-01-19 修回日期:2010-06-22 发布日期:2010-07-05
  • 通讯作者: 王长生 E-mail:chwangcs@lnnu.edu.cn

Theoretical Studies on the Dehydration Reaction Mechanism of 2-Phospho-D-glycerate

QU Wei, WANG Chang-Sheng   

  1. (School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029)
  • Received:2010-01-19 Revised:2010-06-22 Published:2010-07-05
  • Contact: Chang-Sheng WANG E-mail:chwangcs@lnnu.edu.cn

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1002

被引次数

4

采用密度泛函理论B3LYP方法研究了蛋白质和水环境下2-磷酸甘油酸脱水生成磷酸烯醇式丙酮酸的反应机理. 优化得到了反应物、过渡态及产物的几何构型并计算了反应势垒. 研究结果表明: 没有H2O参与时, 反应需要通过四元环过渡态完成, 反应势垒高达287.7 kJ/mol, 常温下难以进行|有H2O参与时, 反应可以通过六元环过渡态完成, 反应势垒大为降低|Mg2＋的参与可使反应势垒进一步降低|蛋白质环境下两个Mg2＋和一个H2O的共同作用可使反应势垒降低至91.2 kJ/mol, 从而使反应在常温下容易进行.

关键词: 2-磷酸甘油酸, 磷酸烯醇式丙酮酸, 反应势垒

The dehydration reaction mechanism of 2-phospho-D-glycerate to form phosphoenolpyruvate in water and protein environments were studied by the density function theory B3LYP method. The optimal structures of reactants, transition states and products were located at the B3LYP/6-31G* level of theory. The reaction barriers were then predicted at the B3LYP/6-311＋＋G(3df,2p) level of theory. The calculation results show that a high reaction barrier (287.7 kJ/mol) exists for the pathway in which no water molecule is involved|whereas the reaction barrier is lowered obviously for the pathway in which a water molecule is involved because of the formation of a six-membered ring transition state structure. The participation of the Mg2＋ ion can further lower the reaction barrier. Including two Mg2＋ ions and one water molecule can reduce the reaction barrier to 91.2 kJ/mol, indicating that a water molecule as well as Mg2＋ ions plays a very important role in the dehydration reaction of 2-phospho-D-glycerate.

Key words: 2-phospho-D-glycerate, phosphoenolpyruvate, reaction barrier