Two-Step Chemoenzymatic Detection of N-Acetylneuraminic Acid−α(2-3)-Galactose Glycans
摘要:
Sialic acids are typically linked alpha(2-3) or alpha(2-6) to the galactose that located at the non-reducing terminal end of glycans, playing important but distinct roles in a variety of biological and pathological processes. However, details about their respective roles are still largely unknown due to the lack of an effective analytical technique. Herein, a two-step chemoenzymatic approach for the rapid and sensitive detection of N-acetylneuraminic acid-alpha(2-3)-galactose glycans is described.
Two-Step Chemoenzymatic Detection of <i>N</i>-Acetylneuraminic Acid−α(2-3)-Galactose Glycans
作者:Liuqing Wen、Yuan Zheng、Kuan Jiang、Mingzhen Zhang、Shukkoor Muhammed Kondengaden、Shanshan Li、Kenneth Huang、Jing Li、Jing Song、Peng George Wang
DOI:10.1021/jacs.6b07132
日期:2016.9.14
Sialic acids are typically linked alpha(2-3) or alpha(2-6) to the galactose that located at the non-reducing terminal end of glycans, playing important but distinct roles in a variety of biological and pathological processes. However, details about their respective roles are still largely unknown due to the lack of an effective analytical technique. Herein, a two-step chemoenzymatic approach for the rapid and sensitive detection of N-acetylneuraminic acid-alpha(2-3)-galactose glycans is described.
Enhanced Detection of Sialylated and Sulfated Glycans with Negative Ion Mode Nanoliquid Chromatography/Mass Spectrometry at High pH
作者:Kristina A. Thomsson、Malin Bäckström、Jessica M. Holmén Larsson、Gunnar C. Hansson、Hasse Karlsson
DOI:10.1021/ac902602e
日期:2010.2.15
Negative ion mode nanoliquid chromatography/mass spectrometry (nano-LC/MS) on porous graphitic carbon columns at pH 11 was studied and compared to capillary LC/MS at pH 8 for the analysis of neutral and acidic glycan alditols. Oligosaccharides were chromatographed with an acetonitrile gradient containing 0.04% ammonium hydroxide and analyzed with a linear ion trap mass spectrometer (LTQ) equipped with a modified nanospray interface. Analysis of acidic N- and O-glycan standards revealed that good quality MS/MS spectra could be obtained when loading 1−3 fmol, a 10-fold increase in sensitivity compared to capillary-LC/MS at pH 8. Analysis of a complex mixture of O-glycans from porcine colonic mucins with nano-LC/MS and MS/MS at high pH revealed 170 oligosaccharides in one analysis, predominantly corresponding to sulfated glycans with up to 11 residues. Analysis of the same sample with capillary-LC/MS showed a lower sensitivity for multiply sulfated glycans. Nano-LC/MS of O-linked oligosaccharides on MUC2 from a human colon biopsy also illustrated that the ionization of oligosaccharides with multiple sialic acid groups was increased compared to those with only one sialic acid residue. Nano-LC/MS at high pH is, thus, a highly sensitive approach for the analysis of acidic oligosaccharides.