分析化学2011，Vol.39Issue(1)：99-102,4.
基质辅助激光解吸电离飞行时间质谱法区分大肠杆菌糖基转移酶基因
Differentiation of Specific Function of Glycosyltransferase Gene by Matrix Assisted Laser Desorption-Time of Flight-Mass Spectrometry
摘要
Abstract
The glycosyltransferases(GTs) assembling the O-chain utilize lipid-linked acceptor substrates and nucleotide sugar donor substrates. The difficulty in characterization and discriminate enzymatic products preclude the elucidation of the specific function of putative GTs. In this study, highenergy collision induced dissociation(CID)-negative-ion mode matrix-assisted laser desorption-ionization time-of-flight mass spectrometry(MALDI TOF MS) was used to differentiate wfgD(in E. coli O152 O antigen gene cluste) product and wfgD(in E. coli O77 O antigen gene cluste) product. By the mass number analysis, it was found that nearly all of the CID fragment ions were produced by cleavages of diphosphate moiety and glycosidic linkage, while no ring fragmentation was produced. The experimental results demonstrate that the differences in the intensity ratio of fragment ions of [B3] /[Y3] allowed unambiguous differentiation of wfgD product and wfgD product, and when 1 kV is used as the collision energy, the change of collision gas pressure can affect the intensity ratio of fragment ions of [B3]/[Y3]. It was concluded that the abundances of CID fragment ions depended on the stereochemistry of the glycosyl donors in the cleavage of the diphosphate moiety and glycosidic linkage of the lipooligosaccharides(LOS) enzymatic product in MALDI-TOF mass spectra, and CID-MALDI TOF MS analysis of LOS enzymatic product is likely to prove an invaluable tool that can be used to determine the pecificity of O-antigen GT genes.关键词
脂寡糖/糖基转移酶/基质辅助激光解吸离子化-飞行时间质谱Key words
Glucosyltransferase/ Lipooligosaccharide/ Matrix-assisted laser desorption-time of flightmass spectrometry引用本文复制引用
周大炜,刘斌,吴俊丽,胡波,齐源远..基质辅助激光解吸电离飞行时间质谱法区分大肠杆菌糖基转移酶基因[J].分析化学,2011,39(1):99-102,4.基金项目
本文系南开大学引进人才科研启动资金(No.J02006)资助 （No.J02006）
