Thermodynamics of apocytochrome b5 unfolding.


Abstract

Apocytochrome b5 from rabbit liver was studied by scanning calorimetry, limited proteolysis, circular dichroism, second derivative spectroscopy, and size exclusion chromatography. The protein is able to undergo a reversible two-state thermal transition. However, transition temperature, denaturational enthalpy, and heat capacity change are reduced compared with the holoprotein. Apocytochrome b5 stability in terms of Gibbs energy change at protein unfolding (delta G) amounts to delta G = 7 +/- 1 kJ/mol at 25 degrees C (pH 7.4) compared with delta G = 25 kJ/mol for the holoprotein. Apocytochrome b5 is a compact, native-like protein. According to the spectral data, the cooperative structure is mainly based in the core region formed by residues 1-35 and 79-90. This finding is in full agreement with NMR data (Moore, C.D. & Lecomte, J.T.J., 1993, Biochemistry 32, 199-207). Study holds ProTherm entries: 11521, 11522 Extra Details: apocytochrome b5; protein folding; scanning calorimetry; thermodynamics

Submission Details

ID: vYn8fuft3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:42 p.m.

Version: 1

Publication Details
Pfeil W,Protein Sci. (1993) Thermodynamics of apocytochrome b5 unfolding. PMID:8401233
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
1HKO 2003-03-18 NMR structure of bovine cytochrome b5
1BLV 1998-07-29 SOLUTION STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5 IN THE PRESENCE OF 2 M GUANIDINIUM CHLORIDE: MONITORING THE EARLY STEPS IN PROTEIN UNFOLDING
5XEE 2018-02-14 NMR solution structure of the aromatic mutant H43F H67F cytochrome b5
1I5U 2001-03-21 SOLUTION STRUCTURE OF CYTOCHROME B5 TRIPLE MUTANT (E48A/E56A/D60A)
2AXX 1998-03-04 THE SOLUTION STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, NMR, 21 STRUCTURES
1IEU 1997-04-21 APOCYTOCHROME B5, PH 6.2, 298 K, NMR, 10 STRUCTURES
1IB7 2001-04-04 SOLUTION STRUCTURE OF F35Y MUTANT OF RAT FERRO CYTOCHROME B5, A CONFORMATION, ENSEMBLE OF 20 STRUCTURES
2I96 2007-09-04 Solution structure of the oxidized microsomal human cytochrome b5
5XE4 2018-02-14 NMR solution structure of the aromatic mutant H43W H67F cytochrome b5
1DO9 2000-01-05 SOLUTION STRUCTURE OF OXIDIZED MICROSOMAL RABBIT CYTOCHROME B5. FACTORS DETERMINING THE HETEROGENEOUS BINDING OF THE HEME.
2M33 2013-02-06 Solution NMR structure of full-length oxidized microsomal rabbit cytochrome b5
1F03 2000-06-21 SOLUTION STRUCTURE OF OXIDIZED BOVINE MICROSOMAL CYTOCHROME B5 MUTANT (E44A, E48A, E56A, D60A) AND ITS INTERACTION WITH CYTOCHROME C
1NX7 2004-06-15 Solution Structure of Oxidized Bovine Microsomal Cytochrome B5
1I87 2001-05-16 SOLUTION STRUCTURE OF THE WATER-SOLUBLE FRAGMENT OF RAT HEPATIC APOCYTOCHROME B5
1IET 1997-04-21 APOCYTOCHROME B5, PH 6.2, 298 K, NMR, MINIMIZED AVERAGE STRUCTURE
1AQA 1997-09-17 SOLUTION STRUCTURE OF REDUCED MICROSOMAL RAT CYTOCHROME B5, NMR, MINIMIZED AVERAGE STRUCTURE
1SH4 2004-08-10 Solution structure of oxidized bovine microsomal cytochrome B5 Mutant V45H
1JEX 2001-07-11 SOLUTION STRUCTURE OF A67V MUTANT OF RAT FERRO CYTOCHROME B5
1F04 2000-06-21 SOLUTION STRUCTURE OF OXIDIZED BOVINE MICROSOMAL CYTOCHROME B5 MUTANT (E44A, E48A, E56A, D60A) AND ITS INTERACTION WITH CYTOCHROME C
1I8C 2001-05-16 SOLUTION STRUCTURE OF THE WATER-SOLUBLE FRAGMENT OF RAT HEPATIC APOCYTOCHROME B5
1J0Q 2003-08-12 Solution Structure of Oxidized Bovine Microsomal Cytochrome b5 mutant V61H
1BFX 1998-08-12 THE SOLUTION NMR STRUCTURE OF THE B FORM OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, MINIMIZED AVERAGE STRUCTURE
1AW3 1998-02-04 THE SOLUTION NMR STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, MINIMIZED AVERAGE STRUCTURE
1B5A 1998-06-17 RAT FERROCYTOCHROME B5 A CONFORMATION, NMR, 1 STRUCTURE
1MNY 2002-11-13 Dimethyl propionate ester heme-containing cytochrome b5
1B5B 1998-06-17 RAT FERROCYTOCHROME B5 B CONFORMATION, NMR, 1 STRUCTURE
1AXX 1998-03-04 THE SOLUTION STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, NMR, 19 STRUCTURES
3X34 2015-07-15 0.76 Crystal structure of the reduced form of the solubilized domain of porcine cytochrome b5 in form 1 crystal
3X32 2015-07-15 0.83 Crystal structure of the oxidized form of the solubilized domain of porcine cytochrome b5 in form 1 crystal
3X33 2015-07-15 0.93 Crystal structure of the oxidized form of the solubilized domain of porcine cytochrome b5 in form 2 crystal
3X35 2015-07-15 0.95 Crystal structure of the reduced form of the solubilized domain of porcine cytochrome b5 in form 2 crystal
1CYO 1994-11-30 1.5 BOVINE CYTOCHROME B(5)
3OZZ 2011-09-14 1.7 Structure of a cytochrome b5 core-swap mutant
1M2I 2003-03-18 1.8 Crystal structure of E44A/E56A mutant of cytochrome b5
1M20 2002-09-11 1.8 Crystal Structure of F35Y Mutant of Trypsin-solubilized Fragment of Cytochrome b5
1M2M 2003-03-18 1.8 Crystal structure of E44A/E48A/E56A/D60A mutant of cytochrome b5
1LQX 2002-09-04 1.8 Crystal structure of V45E mutant of cytochrome b5
1U9U 2005-02-01 1.86 Crystal structure of F58Y mutant of cytochrome b5
1LR6 2002-09-04 1.9 Crystal structure of V45Y mutant of cytochrome b5
1M59 2003-03-18 1.9 Crystal Structure of P40V Mutant of Trypsin-solubilized Fragment of Cytochrome b5
1EHB 2000-08-09 1.9 CRYSTAL STRUCTURE OF RECOMBINANT TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5
1U9M 2005-02-01 2.0 Crystal structure of F58W mutant of cytochrome b5
1ES1 2000-08-09 2.1 CRYSTAL STRUCTURE OF VAL61HIS MUTANT OF TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5
4HIN 2013-10-16 2.4 2.4A Resolution Structure of Bovine Cytochrome b5 (S71L)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
93.1 Cytochrome b5 P00168 CYB5_ALOSE
90.4 Cytochrome b5 P56395 CYB5_MOUSE
92.6 Cytochrome b5 P00167 CYB5_HUMAN
91.5 Cytochrome b5 P00173 CYB5_RAT
93.6 Cytochrome b5 P00170 CYB5_HORSE
100.0 Cytochrome b5 P00169 CYB5_RABIT
90.3 Cytochrome b5 P00171 CYB5_BOVIN
93.6 Cytochrome b5 P00172 CYB5_PIG