Glebska Jolanta, Koppenol Willem H
Inorganic Institute, Department of Chemistry and Applied Biosciences, Eidgenössische Technische Hochschule Zürich (Hönggerberg), CH-8093 Zürich, Switzerland.
Free Radic Biol Med. 2005 Apr 15;38(8):1014-22. doi: 10.1016/j.freeradbiomed.2004.12.028.
The kinetics of the oxidation of Pholasin by peroxynitrite, which leads to emission of light, were studied. The reaction shows a lag phase, which is smaller at higher peroxynitrite-to-Pholasin ratios. The total light emission approximately doubles from pH 5 to 9 and decreases precipitously to half the pH 5 value at pH 10. Dioxygen and carbon dioxide accelerate the reaction course, but they do not change significantly the reaction yield. Chemiluminescence of Pholasin is suppressed by antioxidants, but no significant shift is noticed in the time at which light emission is maximal. The chemiluminescence intensity is strongly dependent on the potassium concentration, although it is not significantly affected by lithium, cesium, or magnesium; potassium decreases luminescence. The mechanism of the peroxynitrite-induced oxidation of Pholasin may start with the reversible formation of a protein-peroxynitrite intermediate, or a first oxidation product, followed in subsequent steps by decomposition and light emission. However, many questions concerning the mechanism of the light emission remain to be elucidated.
研究了过氧亚硝酸盐氧化海笋素导致发光的动力学。该反应呈现出一个滞后阶段，在过氧亚硝酸盐与海笋素比例较高时滞后阶段较小。总发光量从pH 5到pH 9大约翻倍，而在pH 10时急剧下降至pH 5时的一半。氧气和二氧化碳加速反应进程，但它们对反应产率没有显著影响。抗氧化剂会抑制海笋素的化学发光，但发光最大值出现的时间没有明显变化。化学发光强度强烈依赖于钾离子浓度，尽管锂、铯或镁对其没有显著影响；钾会降低发光。过氧亚硝酸盐诱导海笋素氧化的机制可能始于蛋白质 - 过氧亚硝酸盐中间体或首个氧化产物的可逆形成，随后在后续步骤中发生分解并发光。然而，关于发光机制仍有许多问题有待阐明。
