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-pr...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 results 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.展开更多
文摘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 results 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.
