利用磺基异硫氰酸苯酯化学辅助方法鉴定磷酸化肽修饰位点  

Identification of Phosphopeptide Modification Sites Based on Chemically-Assisted Method Using 4-Sulfophenyl Isothiocyanate Derivatization by Mass Spectrometry

作　　者：陈平[1] 李水明[1] 刘宇[2] 刘中华[1] 熊继先[1] 孙亚兰[1] 曹锐[1] 梁宋平[1] 

机构地区：[1]湖南师范大学生命科学学院,长沙410081 [2]中南大学湘雅医学院,长沙410078

出　　处：《中国生物化学与分子生物学报》2006年第7期591-598,共8页Chinese Journal of Biochemistry and Molecular Biology

基　　金：国家自然科学基金资助项目No:39990600~~

摘　　要：利用MALDI-TOF质谱结合磺基异硫氰酸苯酯(SPITC)化学辅助的从头测序(de novosequencing)方法,将用固相金属离子亲和色谱(immobilized metal affinity chromatography,IMAC)选择性地从混合物中亲和提取的磷酸肽进行磷酸化位点测定,该方法只有肽键断裂产生的带C端的碎片离子系列(y+离子系列)出现在质谱图中,图谱背景清晰,信噪比高,单纯的y+片段离子系列使得谱图解析变得非常容易,对于多磷酸化肽的磷酸化位点,不需借助于任何软件,只需简单地计算两峰之间的分子量之差即可确定.Phosphorylated peptides have been detected and phosphorylation modified sites have been identified very sensitively by combining immobilized metal affinity chromatography （IMAC） affinity capture with chemically assisted de novo sequencing followed 4-sulfophenyl isothiocyanate （SPITC） derivatization by MALDI-TOF mass spectrometry. The N-terminal sulfonation of phosphopeptide by SPITC enhanced MALDI- TOF-PSD fragmentation signals and produced a spectrum containing only y^＋ ions. This method facilitated de novo sequencing and spectrum interpretation. The characterization of phosphorylated sites can simply calculated from mass differences between the adjacent y-ion, and advanced software is not need.

关 键 词：SPITC 磷酸化位点 从头测序 质谱 

分 类 号：Q5[生物学—生物化学] Q51