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甜菜碱醛脱氢酶(BADH)在植物抗逆反应中发挥着重要作用。文中从胡杨cDNA克隆到2个甜菜碱醛脱氢酶基因,分别命名为PeBADH1和PeBADH2。PeBADH1和PeBADH2均编码503个氨基酸的蛋白质,预测分子量分别是54.93 kDa和54.90 kDa。组织表达模式分析发现这2个基因在正常生长、盐和H2O2胁迫下,在不同组织中的表达模式有较大差异。在大肠杆菌中表达并纯化了2个基因的重组蛋白。酶活性分析显示PeBADH1和PeBADH2蛋白对底物的活性分别是0.073μmol/(min.mg)和0.107μmol/(min.mg)。热力学稳定性分析显示这2个蛋白的热力学稳定性具有明显差异。因此,基因表达模式差异与蛋白质酶学性质的不同预示着这2个基因可能存在功能上的分化。
Betaine aldehyde dehydrogenase (BADH) plays an important role in plant resistance to stress. In this paper, two betaine aldehyde dehydrogenase genes were cloned from Populus euphratica and named PeBADH1 and PeBADH2 respectively. Both PeBADH1 and PeBADH2 encodes a protein of 503 amino acids with predicted molecular weights of 54.93 kDa and 54.90 kDa, respectively. Tissue expression pattern analysis found that these two genes in normal growth, salt and H2O2 stress, the expression patterns in different tissues are quite different. Recombinant proteins of two genes were expressed and purified in E. coli. Enzyme activity analysis showed that the substrate activity of PeBADH1 and PeBADH2 proteins were 0.073 μmol / (min.mg) and 0.107 μmol / (min.mg), respectively. Thermodynamic stability analysis showed that the thermodynamic stability of the two proteins have significant differences. Therefore, the differences in gene expression patterns and proteomic properties indicate that these two genes may have functional differentiation.