de Borba Thais M, Machado Taiele B, Brandelli Adriano, Kalil Susana J
Laboratório de Microbiologia e Biosseparações, Escola de Química de Alimentos, Universidade Federal do Rio Grande, Rio Grande, RS , 96203-900, Brazil.
Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS , 91501-970, Brazil.
Biotechnol Prog. 2018 Sep;34(5):1102-1108. doi: 10.1002/btpr.2672. Epub 2018 Jul 31.
The parameters half-life, z value, enthalpy, entropy, and free energy were evaluated in the temperature range of 40 to 55°C for a Bacillus sp. P45 protease present in a medium composed of ionic liquid (IL) and organic solvent. The protease was previously treated in IL [Emim][Tf N] and increased activity was observed in four out of five organic solvents tested. The reaction medium containing acetone and IL (1:1 v/v ratio) was more stable than the buffer medium, with half-life of 2.4 h at 55°C. Thermodynamic parameters values showed there was probably less rupture of non-covalent bonds that stabilize the protein structure, which promoted the protease P45 stabilization. According to this study it was concluded that the protease P45 in a medium composed of [Emim][Tf N] and acetone may be used at higher temperatures than those employed in buffer or medium containing organic solvent. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1102-1108, 2018.
在40至55°C的温度范围内，对存在于由离子液体（IL）和有机溶剂组成的培养基中的芽孢杆菌属P45蛋白酶的半衰期、z值、焓、熵和自由能等参数进行了评估。该蛋白酶先前在IL [Emim][Tf N]中进行了处理，并且在所测试的五种有机溶剂中有四种观察到活性增加。含有丙酮和IL（体积比1:1）的反应介质比缓冲介质更稳定，在55°C下的半衰期为2.4小时。热力学参数值表明，稳定蛋白质结构的非共价键可能较少断裂，这促进了蛋白酶P45的稳定。根据这项研究得出结论，由[Emim][Tf N]和丙酮组成的培养基中的蛋白酶P45在比缓冲液或含有有机溶剂的培养基中使用的温度更高时仍可使用。© 2018美国化学工程师学会生物技术进展，2018 © 2018美国化学工程师学会生物技术进展，34:1102 - 1108，2018。
