Vol 52(2018) N 1 p. 30-35; DOI 10.1134/S0026893318010028
A.Y. Yegorov1*, S.A. Potekhin2
Lysozyme Stabilization under High Pressure: Differential Scanning Microcalorimetry1Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow oblast, 142290 Russia
2Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow oblast, 142290 Russia
Received - 2017-06-02; Accepted - 2017-06-22
The heat denaturation of lysozyme has been studied by high-pressure differential scanning microcalorimetry. It has been demonstrated that an increase in pressure has different influence on denaturation temperature and enthalpy at different pH values. It has been established that the pressure increase has no appreciable effect on the transition cooperativity. The experimental data have been analyzed using an equilibrium model of transition between two states. Partial molar volume changes accompanying the denaturation as well as isothermal compressibility and thermal expansibility coefficients have been assessed. In contrast to the denaturation of most globular proteins, the lysozyme denaturation under conditions of the experiment was accompanied by positive volume changes. Possible reasons for this unusual behavior have been discussed.
lysozyme, differential scanning microcalorimetry, high pressure, denaturation volume change