谷胱甘肽与氨基酸非共价复合物的碎片化反应  

Fragmentation Process of Non-Covalent Complexes of Glutathione with Amino Acids

作　　者：储艳秋[1] 蒋公羽[1] 姜丹[1] 王青[1] 丁传凡[1] 

机构地区：[1]复旦大学化学系激光化学研究所,上海200433

出　　处：《质谱学报》2010年第1期12-17,共6页Journal of Chinese Mass Spectrometry Society

基　　金：国家自然科学基金(25027004)资助

摘　　要：为了探讨非共价复合物的碎片化反应机理,选择谷胱甘肽和氨基酸复合物研究影响碎片化反应的主要因素。串级质谱结果表明,碰撞气体密度(CGT)和碰撞能量是影响非共价复合物碎片化反应的两个主要因素,对谷胱甘肽复合物碎片化产物的生成途径会有明显的影响。当碰撞气体密度恒定在50×1013mole-cules/cm2,碰撞能量在小于100 eV范围内,复合物His-GSH都能发生碎裂,断裂位点容易发生在非共价键上,生成原来组分[His+H]+和[GSH+H]+离子,但没有发生进一步碎裂。当碰撞能量一定(恒定为30eV),碰撞气体密度为50×1013molecules/cm2时,His-GSH复合物碎裂后的产物同样为[His+H]+和[GSH+H]+。然而,当碰撞气体密度上升至75×1013molecules/cm2时,除非共价键发生碎裂外,共价键也会发生碎裂,产生更小的碎片离子y2,b2。当碰撞气体密度上升为175×1013molecules/cm2时,His也开始碎裂,生成m/z110[His-H2O-CO+H]+。三级串级质谱MS3实验确认,Lys-GSH复合物中谷胱甘肽碎裂后产生的y2碎片离子会进一步碎裂。To explore the fragmentation reactions of non-covalent complex, the complex of glutathione（GSH） and amino acids were chosen to investigate the main factors affecting the fragmentation process. The secondary tandem mass spectrometry（MS^2） results indicated that collision gas thickness（CGT） and collision energy are two important conditions affecting the fragmentation pathway of glutathione complex. When the CGT maintained at 50 × 10^13 molecules/cm^2 , increasing collision energy from 5 eV to 80 eV, the dissociation of His- GSH complex took place, leading to the formation of [His＋H]＋ and [GSH＋H]^＋. However, it could be seen that no further dissociation of GSH occurred, and the fragmentation of noncovalent bond was the main pathway of the complex. When CGT rose up to 75×10^13 molecules/cm^2, the covalent bond also began to dissociate, leading to the formation of y2 and b2 for glutathione. Such phenomena could be also observed in Lys-GSH complex. To confirm the fragment ion y2 of glutathione, MS^3 was also performed and yl was detected.

关 键 词：氨基酸 谷胱甘肽 非共价复合物 碰撞诱导解离 碎片化反应 

分 类 号：O657.63[理学—分析化学] O641.6[理学—化学]