SEPARATION AND CHARACTERIZATION OF O-DEACYLATED LIPOOLIGOSACCHARIDES AND GLYCANS DERIVED FROM MORAXELLA-CATARRHALIS USING CAPILLARY ELECTROPHORESIS ELECTROSPRAY MASS-SPECTROMETRY AND TANDEM MASS-SPECTROMETRY
J. Kelly et al., SEPARATION AND CHARACTERIZATION OF O-DEACYLATED LIPOOLIGOSACCHARIDES AND GLYCANS DERIVED FROM MORAXELLA-CATARRHALIS USING CAPILLARY ELECTROPHORESIS ELECTROSPRAY MASS-SPECTROMETRY AND TANDEM MASS-SPECTROMETRY, Analytical biochemistry, 233(1), 1996, pp. 15-30
Electrophoretic methods have been developed for the analysis of comple
x carbohydrates derived from lipooligosaccharides (LOS) of Moraxella c
atarrhalis using capillary electrophoresis coupled to electrospray mas
s spectrometry (CE-ESMS). Separation of lipooligosaccharides (LOS) ari
sing from mild hydrazinolysis of the intact lipopolysaccharides (LPS)
was achieved using aqueous ammonium formate, and enabled identificatio
n of sites of heterogeneity (phosphates, phosphoethanolamine, and pend
ant acyl groups) on either the lipid A or the core oligosaccharide, Mo
re complex mixtures of carbohydrates obtained from the complete deacyl
ation and dephosphorylation of LOS were amenable to electrophoretic co
nditions using both anionic and cationic separation, In particular, el
ectrophoretic conditions were developed which permitted resolution of
closely related oligosaccharides according to the number of carbohydra
te residues appended to the core structure, Structural characterizatio
n of carbohydrates and LOS released from the hydrazinolysis and acid h
ydrolysis treatment of the intact LPS was achieved using tandem mass s
pectrometry (MS-MS) for samples introduced by direct flow injection. T
aken together, the combination of CE-ESI-MS and MS-MS analyses provide
d valuable information on the heterogeneity of the LOS population in w
hich a significant level of variability was found mostly in the lipid
A portion.