Electrochemical analysis of the effect of Ca2+ on cardiolipin-cytochrome c interaction.
Mitochondrial Ca2+ has been considered a trigger for the release of cytochrome c, which is a critical and early event in the induction of cell apoptosis, although the molecular mechanism underlying this effect is still not fully understood. Here we investigate the interaction between cytochrome c and cardiolipin and the effect of Ca2+ on this interaction using electrochemical methods. Experimental results revealed that modification of cardiolipin onto the surface of a pyrolytic graphite electrode could lead to a rapid direct electron transfer of cytochrome c through the electrostatic interaction between the protein and the cardiolipin. Addition of Ca2+ to the test solution containing cytochrome c could cause the decrease of the redox peaks of the protein, and the peaks could be recovered when Ca2+ was chelated by ethylenediaminetetraacetate. The cardiolipin-cytochrome c interaction and the Ca2+ effect were also investigated with the variation of the charges of lipids, buffer solutions, reaction time, and valencies of cations for comparison.
Huang
Yinxi
Y
Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, PR China.
Liu
Lei
L
Shi
Chang
C
Huang
Junyi
J
Li
Genxi
G
D000818:Animals; D002118:Calcium / Q000737:chemistry / Q000378:metabolism*; D002308:Cardiolipins / Q000378:metabolism*; D002417:Cattle; D045304:Cytochromes c / Q000378:metabolism*; D004563:Electrochemistry; D006736:Horses; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism; D011485:Protein Binding
D002308:Cardiolipins; D045304:Cytochromes c; D002118:Calcium