Thermodynamics of the equilibrium unfolding of oxidized and reduced Saccharomyces cerevisiae iso-1-cytochromes c.


Abstract

We report thermodynamic data for the chemical denaturation of iso-1-cytochromes c from Saccharomyces cerevisiae having amino acid substitutions R38A, N52I, and F82S in all possible combinations. The guanidine hydrochloride denaturation of isolated proteins was monitored by fluorescence measurements. The redox potentials, Eo', for both the folded and unfolded conformations have been measured. Free energy changes of chemical unfolding together with direct electrochemical measurement of the free energy changes of reduction for both the native and unfolded proteins yield a complete thermodynamic cycle, which includes four states of cytochrome c: oxidized folded, oxidized unfolded, reduced folded, and reduced unfolded. Completed cycles illustrate that the stability of cytochrome c to denaturing conditions is different for each amino acid substitution by an amount that depends on the heme oxidation state. Thus, the differential protein stability cannot be interpreted simply in terms of a hydrophobic effect, without also considering coupled Coulombic effects. Study holds ProTherm entries: 4519, 4520, 4521, 4522, 4523, 4524, 4525, 4526 Extra Details:

Submission Details

ID: QTJQSe8P3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:25 p.m.

Version: 1

Publication Details
Komar-Panicucci S;Weis D;Bakker G;Qiao T;Sherman F;McLendon G,Biochemistry (1994) Thermodynamics of the equilibrium unfolding of oxidized and reduced Saccharomyces cerevisiae iso-1-cytochromes c. PMID:8068696
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
1CHH 1994-06-01T00:00:00+0000 1.97 STRUCTURAL STUDIES OF THE ROLES OF RESIDUES 82 AND 85 AT THE INTERACTIVE FACE OF CYTOCHROME C
1CHI 1994-06-01T00:00:00+0000 2.0 STRUCTURAL STUDIES OF THE ROLES OF RESIDUES 82 AND 85 AT THE INTERACTIVE FACE OF CYTOCHROME C
1CHJ 1994-06-01T00:00:00+0000 1.9 STRUCTURAL STUDIES OF THE ROLES OF RESIDUES 82 AND 85 AT THE INTERACTIVE FACE OF CYTOCHROME C
1CIE 1994-09-26T00:00:00+0000 1.8 STRUCTURAL AND FUNCTIONAL EFFECTS OF MULTIPLE MUTATIONS AT DISTAL SITES IN CYTOCHROME C
1CIF 1994-09-26T00:00:00+0000 1.9 STRUCTURAL AND FUNCTIONAL EFFECTS OF MULTIPLE MUTATIONS AT DISTAL SITES IN CYTOCHROME C
1CIG 1994-09-26T00:00:00+0000 1.8 STRUCTURAL AND FUNCTIONAL EFFECTS OF MULTIPLE MUTATIONS AT DISTAL SITES IN CYTOCHROME C
1CIH 1994-09-26T00:00:00+0000 1.8 STRUCTURAL AND FUNCTIONAL EFFECTS OF MULTIPLE MUTATIONS AT DISTAL SITES IN CYTOCHROME C
1CRG 1993-08-06T00:00:00+0000 2.0 THE ROLE OF A CONSERVED INTERNAL WATER MOLECULE AND ITS ASSOCIATED HYDROGEN BOND NETWORK IN CYTOCHROME C
1CRH 1993-08-06T00:00:00+0000 1.9 THE ROLE OF A CONSERVED INTERNAL WATER MOLECULE AND ITS ASSOCIATED HYDROGEN BOND NETWORK IN CYTOCHROME C
1CRI 1993-08-06T00:00:00+0000 2.0 THE ROLE OF A CONSERVED INTERNAL WATER MOLECULE AND ITS ASSOCIATED HYDROGEN BOND NETWORK IN CYTOCHROME C

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Cytochrome c iso-1 P00044 CYC1_YEAST
91.0 Cytochrome c iso-1 P25400 CYC_CANGA