Arif Kazmi S, Mills M A, Pitluk Z W, Scott R A
J Inorg Biochem. 1985 May;24(1):9-12. doi: 10.1016/0162-0134(85)85009-1.
The kinetics of dithionite reduction of the oxidized heme nonapeptide fragment of horse heart cytochrome c have been measured as a function of ionic strength at pH 7 and pH 9 by the stopped-flow technique. Dithionite concentration dependences indicate that the radical anion monomer, SO2-., is the active reductant. The pH 7 ionic strength dependence suggests that the heme peptide is reacting as a negatively charged molecule (its overall charge is calculated to be -1). Comparison of these results with the known rate of dithionite reduction of cytochrome c indicates that the heme nonapeptide has substantially greater inherent reactivity than cytochrome c, perhaps due to the greater accessibility of the heme.
通过停流技术，在pH 7和pH 9条件下，测定了连二亚硫酸盐还原马心细胞色素c氧化血红素九肽片段的动力学与离子强度的函数关系。连二亚硫酸盐浓度依赖性表明，自由基阴离子单体SO₂⁻是活性还原剂。pH 7时离子强度依赖性表明，血红素肽作为带负电荷的分子发生反应（其总电荷经计算为-1）。将这些结果与已知的细胞色素c连二亚硫酸盐还原速率进行比较，表明血红素九肽具有比细胞色素c更高的固有反应活性，这可能是由于血红素具有更高的可及性。
