ENHANCEMENT OF SAMPLE LOADINGS FOR THE ANALYSIS OF OLIGOSACCHARIDES ISOLATED FROM PSEUDOMONAS-AERUGINOSA USING TRANSIENT ISOTACHOPHORESIS AND CAPILLARY ZONE ELECTROPHORESIS-ELECTROSPRAY-MASS SPECTROMETRY
S. Auriola et al., ENHANCEMENT OF SAMPLE LOADINGS FOR THE ANALYSIS OF OLIGOSACCHARIDES ISOLATED FROM PSEUDOMONAS-AERUGINOSA USING TRANSIENT ISOTACHOPHORESIS AND CAPILLARY ZONE ELECTROPHORESIS-ELECTROSPRAY-MASS SPECTROMETRY, Electrophoresis, 19(15), 1998, pp. 2665-2676
Citations number
25
Categorie Soggetti
Biochemical Research Methods","Chemistry Analytical
The analysis of underivatized core oligosaccharides arising from mild
acid hydrolysis of lipopolysaccharides from Pseudomonas aeruginosa ser
otype O5 was achieved using a transient isotachophoretic preconcentrat
ion method coupled to capillary zone electrophoresis-electrospray-mass
spectrometry (tCITP-CZE-ESMS). The combination of a tCITP preconcentr
ation step provided a 10- to 50-fold enhancement of sample loading and
a corresponding improvement in sensitivity compared to the convention
al zone electrophoresis format. Electrophoretic conditions, enabling t
he separation of these anionic analytes, were developed to determine p
ossible sites of heterogeneity on either the core or the O-chain struc
tures. The tCITP-CZE-ES-MS technique provided unparalleled resolution
of the different core glycoforms and oligosaccharides obtained from th
e acid cleavage of the native endotoxins whether isolated following co
nventional gel permeation chromatography or obtained from direct hydro
lysis of the bacterial isolates. These investigations also highlighted
the highly phosphorylated nature of these complex cell membrane compo
nents, where the heptose residues of the core oligosaccharide can bear
up to six phosphate groups*.