Redox-Bohr effect in the nine haem cytochrome from Desulfovibrio desulfuricans 27774
نویسندگان
چکیده
Redox titrations followed by visible spectroscopy were performed at various pH values with the nine-haem cytochrome c from Desulfovibrio desulfuricans ATCC 27774 (Dd27774). Macroscopic midpoint reduction potentials of the haems and pKa ox and pKa red values of acid /base centres that interact with the redox centres were estimated by using a thermodynamic model, in which the haems are grouped in three sets, and two acid /base centres are considered. The results show that this cytochrome displays redox-Bohr effects in the physiological pH range and that electrostatic effects dominate the macroscopic interactions between the acid /base and redox centres. # 2002 Elsevier Science B.V. All rights reserved.
منابع مشابه
Solution structures of tetrahaem ferricytochrome c3 from Desulfovibrio vulgaris (Hildenborough) and its K45Q mutant: the molecular basis of cooperativity.
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