Koloczek H, Horie T, Yonetani T, Anni H, Maniara G, Vanderkooi J M
Biochemistry. 1987 Jun 2;26(11):3142-8. doi: 10.1021/bi00385a030.
The effect of cytochrome c peroxidase (CCP) and apoCCP on the fluorescence and phosphorescence of Zn and Sn cytochrome c (cyt c) and the effect of cyt c on the fluorescence and phosphorescence of Zn CCP were examined. We found the following: The fluorescence yields of Zn and Sn cyt c were quenched by about 20% by CCP, consistent with energy transfer between the two chromophores with a separation of about 1.8 nm. The phosphorescence spectrum of Zn cyt c (but not Sn cyt c) shifts by 20 nm to the blue upon complexation with either CCP or apoCCP; at the same time the phosphorescence lifetime of Zn cyt c decreases from 12 +/- 2 to 6 ms with apoCCP addition. Zn CCP phosphorescence decay increases from 8.3 to 9.1 ms upon addition of poly(L-lysine) used to mimic cyt c. It is concluded from these results that binding of the redox partner or an analogue to Zn CCP and Zn cyt c results in a conformational change. The respective phosphorescence lifetimes of Zn and Sn cyt c were 13 and 3 ms in the absence of CCP and 1.6 and 1.1 ms in the presence of CCP; this corresponds to a quenching rate due to CCP of 519 and 570 s-1, for Zn and Sn cyt c, respectively. The phosphorescence of Zn CCP is also affected by native cyt c but is dramatically less than the complementary pair; the quenching rate constant is 17 s-1.(ABSTRACT TRUNCATED AT 250 WORDS)
研究了细胞色素c过氧化物酶（CCP）和脱辅基CCP对锌和锡细胞色素c（cyt c）荧光和磷光的影响，以及细胞色素c对锌CCP荧光和磷光的影响。我们发现以下情况：CCP使锌和锡细胞色素c的荧光产率猝灭约20%，这与两个发色团之间距离约为1.8 nm时的能量转移一致。锌细胞色素c（而非锡细胞色素c）与CCP或脱辅基CCP络合后，其磷光光谱向蓝光方向移动20 nm；同时，加入脱辅基CCP后，锌细胞色素c的磷光寿命从12±2毫秒降至6毫秒。加入用于模拟细胞色素c的聚（L-赖氨酸）后，锌CCP的磷光衰减从8.3毫秒增加到9.1毫秒。从这些结果可以得出结论，氧化还原伴侣或其类似物与锌CCP和锌细胞色素c的结合会导致构象变化。在不存在CCP的情况下，锌和锡细胞色素c各自的磷光寿命分别为13毫秒和3毫秒，在存在CCP的情况下分别为1.6毫秒和1.1毫秒；这对应于CCP对锌和锡细胞色素c的猝灭速率分别为519 s⁻¹和570 s⁻¹。锌CCP的磷光也受天然细胞色素c的影响，但远小于互补对；猝灭速率常数为17 s⁻¹。（摘要截短于25０字）
