Strambini G B
Biophys J. 1987 Jul;52(1):23-8. doi: 10.1016/S0006-3495(87)83184-3.
The rate constant for quenching the phosphorescence of alkaline phosphatase by molecular oxygen was measured as a function of temperature. The results disagree with previous determinations and, contrary to fluorescence quenching, show that diffusion of O2 to this region of the macromolecule is a highly hindered process. When nitric oxide is introduced as a quencher, similarly small rate constants were found. While the activation energy for this process is identical for both quenchers, it is much smaller than for structural fluctuations at the chromophore site as manifested by the intrinsic triplet-state lifetime. These findings are analyzed in terms of a mechanism that takes into account static quenching at large distances and does not require penetration of the quencher all the way to the chromophore.
测定了分子氧猝灭碱性磷酸酶磷光的速率常数与温度的函数关系。结果与先前的测定结果不一致，并且与荧光猝灭相反，表明氧气扩散到该大分子区域是一个高度受阻的过程。当引入一氧化氮作为猝灭剂时，也发现了类似的小速率常数。虽然这两种猝灭剂在此过程中的活化能相同，但比发色团位点的结构波动所表现出的本征三重态寿命的活化能小得多。根据一种考虑远距离静态猝灭且不需要猝灭剂一直穿透到发色团的机制对这些发现进行了分析。
