Cardiolipin activates cytochrome c peroxidase activity since it facilitates H(2)O(2) access to heme.
In this work, the effect of liposomes consisting of tetraoleyl cardiolipin and dioleyl phosphatidylcholine (1 : 1, mol/mol) on the rate of three more reactions of Cyt c heme with H2O2 was studied: (i) Cyt c (Fe2+) oxidation to Cyt c (Fe3+), (ii) Fe...S(Met80) bond breaking, and (iii) heme porphyrin ring decomposition. It was revealed that the rates of all those reactions increased greatly in the presence of liposomes containing cardiolipin and not of those consisting of only phosphatidylcholine, and approximately to the same extent as peroxidase activity. These data suggest that cardiolipin activates specifically Cyt c peroxidase activity not only because it promotes Fe...S(Met80) bond breaking but also facilitates H2O2 penetration to the reaction center.
Vladimirov
Yu A
YA
Faculty of Basic Medicine, Lomonosov Moscow State University, Moscow 117192, Russia. yuvlad@mail.ru
Proskurnina
E V
EV
Izmailov
D Yu
DY
Novikov
A A
AA
Brusnichkin
A V
AV
Osipov
A N
AN
Kagan
V E
VE
D000818:Animals; D001665:Binding Sites; D002308:Cardiolipins / Q000494:pharmacology*; D003578:Cytochrome-c Peroxidase / Q000378:metabolism*; D004789:Enzyme Activation; D005296:Ferrous Compounds / Q000378:metabolism; D006418:Heme / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007501:Iron / Q000737:chemistry; D008081:Liposomes; D008715:Methionine / Q000737:chemistry; D010084:Oxidation-Reduction
D002308:Cardiolipins; D005296:Ferrous Compounds; D008081:Liposomes; D006418:Heme; D008715:Methionine; D006861:Hydrogen Peroxide; D007501:Iron; D003578:Cytochrome-c Peroxidase