Esterases are widely used in the food industry. Here, a new thermophilic bacterium, Geobacillus thermodenitrificans PS01, was isolated and the esterase-encoding gene est1 was cloned, sequenced, and recombinant expressed in Escherichia coli Tuner (DE3). The highest activity of recombinant Est1 was detected at pH 8.0, and 40 °C and the extreme stability was observed at pH 6-9 over 30 days at 4 °C. In particular, Est1 can hydrolyze short- to medium-chain (C2-C10) triglycerides and p-nitrophenyl esters (C2-C12) and was not inhibited by most metal ions. Kinetic parameters of p-nitrophenyl butyrate hydrolysis under optimal conditions were determined: Km, 22.76 μM; kcat, 10,415 s-1; and kcat/Km, 457.53 μM-1 s-1. The outstanding specification of Est1 indicates its potential for use in industrial applications.

中文翻译：

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热树突孢杆菌PS01的嗜热重组酯酶的分离，表达和鉴定。

酯酶广泛用于食品工业。在这里，分离出一种新的嗜热细菌，热地芽孢杆菌（Geobacillus thermodenitrificans）PS01，并将酯酶编码基因est1克隆，测序并在大肠杆菌Tuner（DE3）中重组表达。在pH 8.0和40°C下检测到重组Est1的最高活性，在pH 4-6下30天在pH 6-9观察到极高的稳定性。特别是，Est1可以水解短链至中链（C2-C10）甘油三酸酯和对硝基苯基酯（C2-C12），并且不受大多数​​金属离子的抑制。确定了在最佳条件下对硝基苯甲酸丁酯的水解动力学参数：Km，22.76μM； m / z。kcat，10,415 s-1; 和kcat / Km，457.53μM-1s-1。Est1的出色规格表明其在工业应用中的潜力。