野葛葡糖基转移酶PlUGTs的同源建模及其活性位点分析

本文对PIUGTs进行同源建模，并分析其与底物结合的构象及活性位点。通过SWISS-MODEL在线对P1UGTs进行模板预测和选择，运用Swiss—PdbViewer软件显示和优化，利用ACDLABS绘制糖基供体小分子（酶结合底物），最后通过AutoDock_ADT进行分子对接，并分析PIUGTs酶与不同底物结合的整体构象及分析活性位点。研究结果表明PIUGT1、PIUGT2及PIUGT3均能得到较好的三级构象，并且PIUGT1、PIUGT2与三种底物均可进行较好对接，H18,R278，N359为PIUGTI与三种对接构象活性中心所共有的氨基残基；而G16，H17,V19,T148，N370，E374，E390为PIUGT2与三种对接构象活性中心所共有的氨基残基，但PIUGT3未能得到较好的对接构象。由此推测PIUGT1和PIUGT2均能合成葛根素．而PIUGT3不能催化葛根素的合成。

Homology modeling of glucosyltransferases from Pueraria lobata (Willd.) Ohwi and the analysis of the active motif

In this paper, we present the homology modeling on PIUGTs and the analysis of its active motif and conformation with the substrate. We selected PIUGTs based on the SWISS-MODEL online template predictions , used the Swiss-PdbViewer for displaying and optimization, drawn glycosyl donor molecules by ACDLABS （enzyme substrate）, did molecular docking through the AutoDock_ADT,and analyzed the overall PIUGTs＇ active motif and conformation with the substrates. As a result, PIUGT1, PIUGT2 and PIUGT3 all can get good tertiary conformations, while PIUGT1 and PIUGT2 have good docking with three substrates. H18, R278, N359 are three kinds of amino acid residues both in the conformation of active center of PIUGT1 combined with three substrates, G16, H17, V19, T148 N370, E374 are amino acid residues both in the conformation of active center of PIUGT2 combined with three substrates, PIUGT3 failed to get a good docking conformation.As a result, if this, we concluded conclusion speculation is that PIUGT1 and PIUGT2 can synthesis puerarin, but PIUGT3 can not catalytic synthesis puerarin.