Zhu Hongping, Chen Shimou, Yao Side, Wang Wenfeng
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
J Photochem Photobiol B. 2009 Feb 9;94(2):125-30. doi: 10.1016/j.jphotobiol.2008.11.004. Epub 2008 Nov 27.
The behavior of melatonin in the riboflavin-sensitized photo-oxidation of lysozyme was monitored. Melatonin was found to prevent aggregation of protein and the decrease of enzyme activity induced by photo-oxidation. Electron spin resonance experiments showed that photo-oxidation of lysozyme in the presence of riboflavin resulted in formation of protein radicals, and melatonin was highly effective in reducing the formation of protein radicals. Direct evidence of melatonin's ability for quenching the triplet state of riboflavin and singlet oxygen was presented. A mechanism of the protective effect of melatonin on photo-oxidation of protein was proposed and the physiological relevance was discussed.
监测了褪黑素在核黄素敏化的溶菌酶光氧化过程中的行为。发现褪黑素可防止蛋白质聚集以及光氧化诱导的酶活性降低。电子自旋共振实验表明，在核黄素存在下溶菌酶的光氧化导致蛋白质自由基的形成，而褪黑素在减少蛋白质自由基的形成方面非常有效。提供了褪黑素淬灭核黄素三重态和单线态氧能力的直接证据。提出了褪黑素对蛋白质光氧化保护作用的机制并讨论了其生理相关性。
