Thermal stability and catalytic properties of protease from Bacillus sp. P45 active in organic solvents and ionic liquid

Abstract

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.

Biochemical properties of extracellular protease from Staphylococcus carnosus RT6 isolated from Harbin dry sausages, and its hydrolysis of meat proteins

“…Arrhenius plots of S. carnosus RT6 protease (Figure 3b) indicated that the calculated activation energy ( E a ) was about 24.62 kJ/mol (Table 2), the activation energy was lower than those of other studied, such as Aspergillus fumigatus protease (62 kJ/mol) (Hernández‐Martínez et al., 2011) and Bacillus sp. P45 protease (92.7 kJ/mol) (de Borba et al., 2018), and was higher than that of B. stearothermophilus alkaline protease (17.31 kJ/mol) (Abdel‐Naby et al., 2017). A low E a value was beneficial to the formation of enzyme–substrate complex and therefore required less energy (Abdel‐Naby et al., 2017).…”

The Energies of Activation and Deactivation of 2,4-Dichlorophenol Degradation by Horseradish Peroxidase Immobilized on the Modified Nanofibrous Membrane

“…This confirms that the change in the ∆G # d is the energy barrier for the enzyme deactivation. The higher the ∆G # d is, the more stable the enzyme [27,35]. The increase in the stability of horseradish peroxidase immobilized on the membrane relative to native horseradish peroxidase is accompanied by a decrease of ∆H # and ∆S # values according to an enthalpy-entropy [34].…”

Acetone application for administration of bioactive substances has no negative effects on longevity, fitness, and sexual communication in a parasitic wasp

“…have stabilizing effects even at high concentrations or dosages [68][69][70]. Metabolization of acetone by carboxylation to acetoacetate has been demonstrated in aerobic and anaerobic bacteria [71,72].…”