Thermodynamics of the denaturation of lysozyme in alcohol--water mixtures.


Abstract

The thermal denaturation of lysozyme was studied at pH 2 in aqueous mixtures of methanol, ethanol, and 1-propanol by high sensitivity differential scanning calorimetry (DSC). The most obvious effect of alcohols was the lowering of Td, the temperature of denaturation, increasingly with higher alcohol concentration and longer alkyl chain. Both the calorimetric and van't Hoff enthalpies of denaturation initially increased and then decreased with increasing alcohol concentration, the ratio of the two enthalpies being nearly unity, 1.007 +/- 0.011, indicating the validity of the two-state approximation for the unfolding of lysozyme in these solvent systems. The reversibility of the denaturation was demonstrated by the reversibility of the DSC curves and the complete recovery of enzymic activity on cooling. The changes in heat capacity on unfolding decreased with increasing alcohol concentration for each alcohol. Experimentally determined values of denaturation temperature and of entropy and heat capacity changes were used to derive the additional thermodynamic parameters delta G degrees and delta S degrees for denaturation as a function of temperature for each alcohol--water mixture. Comparison of the thermodynamic parameters with those reported [Pfeil, W., & Privalov, P.L. (1976) Biophys. Chem. 4, 23--50] in aqueous solution at various values of pH and guanidine hydrochloride concentration showed that these latter changes have no effect on the heat capacity changes, whereas the addition of alcohols causes a sharp decrease. Study holds ProTherm entries: 2997 Extra Details: lysozyme; denaturation temperature; thermodynamics; calorimetry,entropy; heat capacity change

Submission Details

ID: RN9kauEv3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:20 p.m.

Version: 1

Publication Details
Velicelebi G;Sturtevant JM,Biochemistry (1979) Thermodynamics of the denaturation of lysozyme in alcohol--water mixtures. PMID:427107
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
2IHL 1993-06-29T00:00:00+0000 1.4 LYSOZYME (E.C.3.2.1.17) (JAPANESE QUAIL)
1FBI 1995-01-19T00:00:00+0000 3.0 CRYSTAL STRUCTURE OF A CROSS-REACTION COMPLEX BETWEEN FAB F9.13.7 AND GUINEA-FOWL LYSOZYME
1GHL 1993-05-04T00:00:00+0000 2.1 THE THREE-DIMENSIONAL STRUCTURE OF PHEASANT AND GUINEA-FOWL EGG LYSOZYMES
1HHL 1993-05-04T00:00:00+0000 1.9 THE THREE-DIMENSIONAL STRUCTURE OF PHEASANT AND GUINEA-FOWL EGG LYSOZYMES
1JHL 1993-05-04T00:00:00+0000 2.4 THREE-DIMENSIONAL STRUCTURE OF A HETEROCLITIC ANTIGEN-ANTIBODY CROSS-REACTION COMPLEX
1BQL 1995-02-03T00:00:00+0000 2.6 STRUCTURE OF AN ANTI-HEL FAB FRAGMENT COMPLEXED WITH BOBWHITE QUAIL LYSOZYME
1DKJ 1996-01-10T00:00:00+0000 2.0 BOBWHITE QUAIL LYSOZYME
1DKK 1996-01-10T00:00:00+0000 1.9 BOBWHITE QUAIL LYSOZYME WITH NITRATE
135L 1993-06-10T00:00:00+0000 1.3 X-RAY STRUCTURE OF MONOCLINIC TURKEY EGG LYSOZYME AT 1.3 ANGSTROMS RESOLUTION
1DZB 2000-02-23T00:00:00+0000 2.0 Crystal structure of phage library-derived single-chain Fv fragment 1F9 in complex with turkey egg-white lysozyme

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
92.3 Lysozyme C P49663 LYSC_PHAVE
93.0 Lysozyme C P81711 LYSC_SYRSO
93.2 Lysozyme C P00702 LYSC_PHACO
94.6 Lysozyme C P24533 LYSC_SYRRE
93.0 Lysozyme C P24364 LYSC_LOPLE
92.2 Lysozyme C P00704 LYSC_NUMME
95.2 Lysozyme C P00703 LYSC_MELGA
95.3 Lysozyme C Q7LZT2 LYSC_TRATE
95.3 Lysozyme C P22910 LYSC_CHRAM
96.1 Lysozyme C P19849 LYSC_PAVCR
95.3 Lysozyme C P00701 LYSC_COTJA
96.1 Lysozyme C Q7LZI3 LYSC_TRASA
96.9 Lysozyme C Q7LZP9 LYSC_LOPIM
96.9 Lysozyme C Q7LZQ0 LYSC_CATWA
96.9 Lysozyme C P00699 LYSC_CALCC
96.9 Lysozyme C P00700 LYSC_COLVI
100.0 Lysozyme C P00698 LYSC_CHICK