Kinetic studies on the interaction of ferricytochrome c with anionic surfactants.
The kinetics of absorbance and fluorescence changes of cytochrome c as induced by an aqueous solution of the anionic surfactant sodium dodecyl sulfate (SDS) or sodium bis(2-ethylhexyl)sulfosuccinate (AOT) are studied. The results are compared with far-UV circular dichroism (CD) spectra. Both surfactants cause similar alterations in the secondary structure of cytochrome c, while their influence on the heme environment of cytochrome c is different. In the presence of AOT below and above critical micellar concentration a conversion of the low-spin native cytochrome c to a denatured low-spin protein not having methionine ligand takes place. In the presence of SDS micelles conversion of the native protein to a denatured mixed-spin form occurs. The changes in the heme group induced by both surfactants occur independently of the alterations in tertiary structure.
Gebicka
L
L
Institute of Applied Radiation Chemistry, Technical University of Lódź, Poland. lgebicka@mitr.p.lodz.pl
Gebicki
J L
JL
D000818:Animals; D000838:Anions; D003574:Cytochrome c Group / Q000737:chemistry*; D006736:Horses; D007700:Kinetics; D009206:Myocardium / Q000201:enzymology; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents / Q000737:chemistry*
D000838:Anions; D003574:Cytochrome c Group; D013501:Surface-Active Agents