The influence of hydrostatic pressure (< or =100 MPa) on denaturant-induced unfolding of hen egg white lysozyme was investigated by means of ultraviolet spectroscopy at various temperatures. Assuming a two-state transition model, the dependence of Gibbs free-energy change of unfolding on the denaturant concentration was calculated. Under applied hydrostatic pressure, these data were interpreted as suggesting that a two-state model is not applicable in a restricted temperature range; the dominant effect of hydrostatic pressure is to affect the cooperativity in protein unfolding due to a chemical equilibrium shift in the direction of the reduction in the system volume. The deviation from the two-state transition model appears to be rationalized by assuming that applied pressure induces an intermediate conformation between the native and unfolded states of the protein. The implication of the thermodynamic stability of protein under pressure was discussed. Study holds ProTherm entries: 11361, 11362, 11363 Extra Details: under 80MPa pressure protein unfolding; intermediate state; hydrostatic pressure;,cooperativity; stability
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:42 p.m.
|Number of data points||3|
|Proteins||Lysozyme C ; Lysozyme C|
|Assays/Quantities/Protocols||Experimental Assay: dG_H2O|
|Libraries||Mutations for sequence KVFGRCELAAAMKRHGLDNYRGYSLGNWVCAAKFESNFNTQATNRNTDGSTDYGILQINSRWWCNDGRTPGSRNLCNIPCSALLSSDITASVNCAKKIVSDGNGMNAWVAWRNRCKGTDVQAWIRGCRL|