中文摘要：

为研究铜胁迫下海州香薷（Elsholtzia haichowensis Sun）非矿区种群细胞壁转化酶（Eh Ncw INV）和矿区种群细胞壁转化酶（Eh Ccw INV）活性差异的机理,运用在线分析工具对细胞壁转化酶基因推导的氨基酸序列进行分析,利用SWISS-MODEL进行同源建模,并将细胞壁转化酶与蔗糖分子进行模拟对接。结果表明,海州香薷两个种群细胞壁转化酶蛋白质在443位点和538位点处存在氨基酸趋异位点,模拟的3D结构非常相似,仅在趋异位点Leu433/Pro433和Tyr538/His538处有差别。Eh Ncw INV、Eh Ccw INV和模拟突变体（Eh Ncw INV-L433P和Eh Ncw INV-Y538H）与蔗糖分子对接形成的催化活性中心构象基本一致,但在空间位置上存在细微差异,氨基酸趋异可能是造成两个种群细胞壁转化酶活性差异的原因之一。

英文摘要：

It was to study the mechanism of enzyme activity difference of cell wall invertase from different populations,one from non-mine population（Eh Ncw INV）,the other from mine population（Eh Ccw INV） in Elsholtzia haichowensis Sun under copper stress. The amino acid sequences of cell wall invertase were analyzed by Ex PASy（http：//au.expasy.org/tools/）. The threedimensional structure was constructed by homologous modeling. The structures of cell wall invertase from two populations of E.haichowensis Sun and non-mine population with each single point mutation in complex with sucrose were simulated. The results showed that there were two divergent amino acids at position 443 and 538 between Eh Ncw INV and Eh Ccw INV. The threedimensional structures were exactly similar between Eh Ncw INV and Eh Ccw INV. It showed difference at Leu433/Pro433 and Tyr538/His538,which were divergent sites. The structures of catalytic active center of Eh Ncw INV,Eh Ccw INV,and simulated mutants（Eh Ncw INV-L433 P,Eh Ncw INV-Y538H） binding with sucrose showed no significant differences. However,there were differences on spatial position. It might be one of the reasons for the difference of cell wall invertase activity between two populations.