Open AccessCytochrome c : A Thermodynamic Study of the Relationship among Oxidation State, Ion‐Binding and Structural Parameters Cation Binding to Horse‐Heart Ferrocytochrome c
Author(s) -
MARGALIT Rimona,
SCHEJTER Abel
Publication year - 1974
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1974.tb03631.x
Subject(s) - chemistry , cytochrome c , proflavine , binding constant , crystallography , molecule , stability constants of complexes , ion , stereochemistry , analytical chemistry (journal) , binding site , chromatography , organic chemistry , biochemistry , mitochondrion , dna
The specific binding of cations to horse heart ferrocytochrome c has been studied, using the gel filtration method. The cations investigated were: Mg 2+ , Co 2+ , cinchonine and proflavine. The stability constants are in the range of 5–8 mM −1 , and the number of binding sites per protein molecule are 1 to 2. The temperature dependence of the stability constant for the Mg 2+ ‐ferrocytochrome system was measured. The thermodynamic parameters were found to be: Δ H 0 obs =+ 12 kcal/mol, Δ G 0 obs , (25°C) =−5.6 kcal/mol and Δ S 0 obs =+ 57 cal × mob 1 × K −1 .