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Published on: February 18, 2014
Changes in the Structure of Cytochrome C Active Center under the Action of Phosphatidic Acid and Temperature
I V Kirilina1, G O Stepanov2, Yu A Vladimirov1
1Pirogov Russian National Research Medical University (Pirogov University), Ministry of Health of the Russian Federation, Moscow, Russia.
Abstract:
The release of cytochrome C into the cytoplasm after formation of a complex with mitochondrial phospholipids underlays the mitochondrial pathway of apoptosis. Changes in the structure of cytochrome C complex active center depending on phosphatidic acid concentration and at different temperatures (25, 37, and 45°C) were studied. Changes in the active center structure were assessed by optical absorption at 695 nm and compared with the intensity of luminol-dependent chemiluminescence which is proportional to the peroxidase activity of cytochrome C-phosphatidic acid complex. It was found that increasing the temperature from 25 to 45°C leads to comparable changes in the conformation of cytochrome C active center and an increase in its peroxidase activity.
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