中国物理B ›› 2002, Vol. 11 ›› Issue (5): 506-508.doi: 10.1088/1009-1963/11/5/318
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇
王敖金, 徐建兴
Wang Ao-Jin (王敖金), Xu Jian-Xing (徐建兴)
摘要: New experimental evidence that a switch controls the reduction of the heme a3-CuB binuclear centre has been observed in the N2-dried thin film of purified cytochrome oxidase. When immersing the enzyme film into the acid phosphate buffer with extremely low concentration of dithionite, a spectrum was given to show a reduction of heme a with no electrons resting on CuA. By increasing dithionite, electrons could be accumulated gradually on CuA, but the binuclear centre still remains in the oxidized state. When the accumulation of electrons on CuA and/or heme a exceeded a threshold, a turnover of reduction of the binuclear centre and oxidation of heme a occurred abruptly. This switch-like action is pH-dependent.
中图分类号: (Charge (electron, proton) transfer in biological systems)