Document Detail

Methylamidation for sialoglycomics by MALDI-MS: a facile derivatization strategy for both α2,3- and α2,6-linked sialic acids.
MedLine Citation:
PMID:  20831242     Owner:  NLM     Status:  MEDLINE    
Neutralization of carboxylic acid is an important means to avoid sialic acid dissociation when sialylated glycans are analyzed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). In this paper, we describe a simple and rapid method to modify the sialic acids of sialylated glycans in the presence of methylamine and (7-azabenzotriazol-1-yloxy) trispyrrolidinophosphonium hexafluorophosphate (PyAOP). After methylamidation, sialylated glycans can be analyzed by MALDI-MS without loss of the sialic acid moiety. The electrospray ionization mass spectrometry (ESI-MS) and MALDI-MS analysis of both 3'- and 6'-sialyllactose derivatives indicated that the quantitative conversion of sialic acids was achieved, regardless of their linkage types. This derivatization strategy was further validated with the N-glycans released from three standard glycoproteins (fetuin, human acid glycoprotein, and bovine acid glycoprotein) containing different types of complex glycans. Most importantly, this derivatization method enabled the successful characterization of N-glycans of sera from different species (human, mouse, and rat) by MALDI-MS. Because of the mild reaction conditions, the modification in sialic acid residues can be retained. This improvement makes it possible to detect sialylated glycans containing O-acetylated sialic acid moieties using MALDI-MS in positive-ion mode.
Xin Liu; Hongyu Qiu; Rhonda Kuo Lee; Wangxue Chen; Jianjun Li
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Analytical chemistry     Volume:  82     ISSN:  1520-6882     ISO Abbreviation:  Anal. Chem.     Publication Date:  2010 Oct 
Date Detail:
Created Date:  2010-09-30     Completed Date:  2011-01-20     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0370536     Medline TA:  Anal Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  8300-6     Citation Subset:  IM    
Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Systems Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Carbohydrate Sequence
Glycomics / methods*
Glycoproteins / chemistry,  metabolism
Lactose / analogs & derivatives,  blood,  chemistry
Methylamines / chemistry
Molecular Sequence Data
Organophosphorus Compounds / chemistry
Polysaccharides / blood,  chemistry
Sialic Acids / blood*,  chemistry
Spectrometry, Mass, Electrospray Ionization / methods
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*
alpha-Fetoproteins / chemistry
Reg. No./Substance:
0/6'-sialyllactose; 0/Glycoproteins; 0/Methylamines; 0/Organophosphorus Compounds; 0/Polysaccharides; 0/Sialic Acids; 0/alpha-Fetoproteins; 63-42-3/Lactose; 74-89-5/methylamine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Combined statistical analyses of peptide intensities and peptide occurrences improves identification...
Next Document:  Computational study of molecules with high intrinsic hyperpolarizabilities.