中文摘要：

来源于嗜热古菌Aeropyrum pernix K1的嗜热酯酶APE1547的晶体结构包含两个结构域．C端为一个规则的邮水解酶结构域．N端结构域是一个有7个“叶片”（Blade）的β-推进器结构．目前，从很多生物中发现和预测到许多不同的含有β-推进器折叠结构的蛋白质，β-推进器的环闭合机制也已经清楚，大部分是依靠第一和最后“叶片”间的疏水相互作用、二硫键、

英文摘要：

Thermophilic esterase APE1547 from Aeropyrum pernix K1 contained a β-propeller with seven blades. There are three hydrogen bonding interactions （Thr127-Gly154, Leu182- Arg145-Glu122） between blades 3 and 4 in the β-propeller domain of the APE1547. To examine the role of these hydrogen bonds, we eliminated these three hydrogen bonds between blades 3 and 4, by site-directed mutagenesis. The analysis resuits of kinetics, thermostability and differential scanning calorimetry（DSC） of the mutants show that Kcat/Km value of each mutation increased, and stability decreased dramatically than wild-type protein. These results strongly suggest that the three specific hydrogen bonds played an important role on maintaining the stability and activity of the esterase APE1547.