摘要
本文以红细胞膜为材料,通过测量磷脂过氧化荧光产物的产生,磷脂组分的损伤以及膜蛋白二级结构的破坏,内源荧光的下降和蛋白SDS-凝胶电泳分析,探讨了甲素光敏作用中蛋白和磷脂的损伤。结果表明:甲素存在时红细胞膜样品照光,使磷脂产生过氧化荧光产物和丙二醛,磷脂组分受到破坏(其中PE与PS较敏感),在膜状态的磷脂比提取的磷脂脂质体中的损伤来得剧烈。同时,膜蛋白二级结构遭到破坏,内源荧光下降。在膜状态中spectrin的损伤比提取出的spectrin的损伤来得严重。据此,我们认为,在甲素光敏作用产生的蛋白和磷脂的损伤过程中,蛋白与磷脂间存在着相互作用和相互影响,使损伤加剧。
The photosensitizer hypocrellin A(H_A) was isolated from a kind of fungusHypocrella bambusae sacc.It is a pery-loquinone derivative with 3 absorptionbands in the visible region at 475 nm.545 nm and 585 nm (Fig.1). Samples of erythrocyte membraneswere irradiated with 250W tungstenlamp (Light intensity:48ergs/mm^2.sec) in the presence of H_A.The follow-ing effects were observed after irradia-tion:(a) diminution in membrane pro-tein SH content (Fig.2),(b) decreasein sensitive amino acid residues,such ashistidine,cysteine and tryptophan(Table 1),(c) photoaggregation ofmembrane proteins (Fig 3) and (d)peroxidation of polyunsaturated lipids(Fig 4).Hence H_A is an effective pho-tosensitizer. Membtanes (2.0mg of protein/ml) were irra-diated for 10 min and 60 min,in the presence of0.1 mM hypocrellin A.Determined according toEllman in membranes solubilized with 1% SDS.Trp was determined according to Spies. H_A itself was irradiated for variousintervals of time,then added to ery-throcyte membranes and allowed tostand for some time.In all cases adecrease in SH content was observed.This suggests that the photooxidationproducts of H_A are stable and cause da-mage in erythrocyte membranes.
出处
《实验生物学报》
CSCD
1990年第1期41-49,共9页
Acta Biologiae Experimentalis Sinica
关键词
竹红菌甲素
红细胞膜
光敏损伤
人
Hypocrellin A.Photodamage.Human Erythrocyte Membranes.
