Thermodynamic investigations of cytochrome b5 unfolding. I. The tryptic fragment of cytochrome b5.


Abstract

Thermal unfolding of the tryptic fragment of the membrane-bound protein, cytochrome b5, which contains the residues 1-90, was investigated by scanning calorimetry, circular dichroism and absorption spectroscopy. The fragment undergoes a reversible two-state transition at about 70 degrees C (neutral pH). The fragment exhibits all the thermodynamic properties of small globular proteins with respect to heat capacity and transitional changes of enthalpy, Gibbs energy and heat capacity. The heat capacity change at unfolding fits into the correlation with the specific amount of nonpolar contacts, which has been found to be valid for small globular proteins (Privalov, P.L. and Khechinashvili, N.N. (1974) J. Mol. Biol. 86, 665-684). The relatively low stabilization energy of the cytochrome b5 fragment (delta trsG25 degrees C = 25 kJ/mol) is discussed in terms of the functional requirements of electron-transfer proteins. Study holds ProTherm entries: 11523, 11524 Extra Details: fragment contains the residues 1-90 membrane-bound protein; two-state transition; nonpolar contacts;,electron-transfer proteins

Submission Details

ID: QTYeMDoy

Submitter: Connie Wang

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

Version: 1

Publication Details
Pfeil W;Bendzko P,Biochim. Biophys. Acta (1980) Thermodynamic investigations of cytochrome b5 unfolding. I. The tryptic fragment of cytochrome b5. PMID:7459384
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
1AQA 1997-09-17 SOLUTION STRUCTURE OF REDUCED MICROSOMAL RAT CYTOCHROME B5, NMR, MINIMIZED AVERAGE STRUCTURE
1JEX 2001-07-11 SOLUTION STRUCTURE OF A67V MUTANT OF RAT FERRO CYTOCHROME B5
1AXX 1998-03-04 THE SOLUTION STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, NMR, 19 STRUCTURES
1HKO 2003-03-18 NMR structure of bovine cytochrome b5
2M33 2013-02-06 Solution NMR structure of full-length oxidized microsomal rabbit cytochrome b5
1IB7 2001-04-04 SOLUTION STRUCTURE OF F35Y MUTANT OF RAT FERRO CYTOCHROME B5, A CONFORMATION, ENSEMBLE OF 20 STRUCTURES
1I8C 2001-05-16 SOLUTION STRUCTURE OF THE WATER-SOLUBLE FRAGMENT OF RAT HEPATIC APOCYTOCHROME B5
1F04 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
1SH4 2004-08-10 Solution structure of oxidized bovine microsomal cytochrome B5 Mutant V45H
1I87 2001-05-16 SOLUTION STRUCTURE OF THE WATER-SOLUBLE FRAGMENT OF RAT HEPATIC APOCYTOCHROME 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
1B5A 1998-06-17 RAT FERROCYTOCHROME B5 A CONFORMATION, NMR, 1 STRUCTURE
1DO9 2000-01-05 SOLUTION STRUCTURE OF OXIDIZED MICROSOMAL RABBIT CYTOCHROME B5. FACTORS DETERMINING THE HETEROGENEOUS BINDING OF THE HEME.
5XEE 2018-02-14 NMR solution structure of the aromatic mutant H43F H67F cytochrome b5
5XE4 2018-02-14 NMR solution structure of the aromatic mutant H43W H67F cytochrome b5
1B5B 1998-06-17 RAT FERROCYTOCHROME B5 B CONFORMATION, NMR, 1 STRUCTURE
2I96 2007-09-04 Solution structure of the oxidized microsomal human cytochrome b5
1MNY 2002-11-13 Dimethyl propionate ester heme-containing cytochrome b5
1IEU 1997-04-21 APOCYTOCHROME B5, PH 6.2, 298 K, NMR, 10 STRUCTURES
1AW3 1998-02-04 THE SOLUTION NMR STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, MINIMIZED AVERAGE STRUCTURE
1I5U 2001-03-21 SOLUTION STRUCTURE OF CYTOCHROME B5 TRIPLE MUTANT (E48A/E56A/D60A)
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
1F03 2000-06-21 SOLUTION STRUCTURE OF OXIDIZED BOVINE MICROSOMAL CYTOCHROME B5 MUTANT (E44A, E48A, E56A, D60A) AND ITS INTERACTION WITH CYTOCHROME C
2AXX 1998-03-04 THE SOLUTION STRUCTURE OF OXIDIZED RAT MICROSOMAL CYTOCHROME B5, NMR, 21 STRUCTURES
1IET 1997-04-21 APOCYTOCHROME B5, PH 6.2, 298 K, NMR, MINIMIZED AVERAGE STRUCTURE
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
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
1M2I 2003-03-18 1.8 Crystal structure of E44A/E56A 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
1EHB 2000-08-09 1.9 CRYSTAL STRUCTURE OF RECOMBINANT TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5
1M59 2003-03-18 1.9 Crystal Structure of P40V Mutant of 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