通过对溶菌酶活性的测量以及利用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(Sodium dodecyl sulfateolyacrylamide gel electrophoresis,SDS-PAGE)对光照后稳态产物的分析,证实在紫外可见波段光照射下杜醌能够诱导溶菌酶的光敏损伤,导致溶菌酶结构破坏和活性降低。研究发现,溶菌酶的光敏损伤途径和损伤产物与杜醌浓度、光照时间、体系的气氛等密切相关,在氮气条件下为I型光敏损伤机制,在有氧条件下对溶菌酶的损伤是以II型反应为主的I型和II型协同作用的结果。同时考察了抗氧化剂–羟基肉桂酸类衍生物对溶菌酶的保护作用。
Organisms produces reactive oxygen species (ROS) throughout their lives. ROS including superoxide anions, hydroxyl radicals, hydrogen peroxide and singlet oxygen whit known to oxidize biological macromolecules, The accumulation of oxidized, or modified, extra- and intra-cellular proteins in vivo cause age-related diseases such as Parkinson’s disease and cataract. Therefore, it is important to study the damage of proteins by photo-sensitizer. Singlet oxygen is a high reactive oxidant in biology systems, and that proteins are a major target for the damage initiated by this reactive species. Reaction with proteins occurs primarily at Trp, Met, Cys, His, and Tyr side-chains with this resulting in the formation of short-lived endo- or hydroperoxides on Trp, His, and Tyr resi- dues. This paper is a brief introduction about the reactions of singlet oxygen with tyrosine and histidine.
