血卟啉衍生物（HPD）对紫膜菌紫质（bR）的光敏化作用

THE PHOTOSENSITIZATION OF BACTERIORHODOPSIN IN PURPLE MEMBRANE INDUCED BY HEMATOPORPHYRIN DERIVATIVE(HPD)

研究了血卟啉衍生物（ＨＰＤ）对嗜盐菌紫膜上蛋白质菌紫质（ｂＲ）的光敏化作用。结果表明，ＨＰＤ与紫膜结合并不影响ｂＲ的光学性质及活性；但经先照射、ＨＰＤ光敏反应后，ｂＲ丧失光循环活性。进一步的探测显示ｂＲ中的视黄醛色素团（ｒｅｔｉｎａｌ）及色氨酸均在光敏反应中受损，反映了除视黄醛色素团有可能直接受损外，深埋于折叠蛋白内部的部分色氨酸残基，亦可能在ＨＰＤ光敏化过程中被损伤。实验证明，单线态氧（１Ｏ２）的作用是ＨＰＤ光敏化ｂＲ的机制之一。

The effects of HPD photosensitixation on bacteriorhodopsin (bR) in purple membrane un studied. The results show that, the incoporation of HPD and purple membrane does not affect the optical property and photocycle activity of bR, however through the HPD photosensitive reaction, the photocycle characteristic of bR is totally lost. The further measurements exhibit the both retinal and tryptophane in bR are damaged during the HPD photosensitization, reflecting the intramural part of membrane protein (the part not exposed on the membrane surface ) can be photodamaged by photosensitization. The singlet oxygen was confirmed to be the main mechanism of bR damage.