Autori: C.Flangea,C.Schiopu, E.Sisu,A.Serb,M.Przybylski,D.G.Seidler,A.D. Zamfir

Editorial: Springer, Anal Bioanal Chem, 395, p.2489-2498, 2009.

Rezumat:

Chondroitin sulfate (CS) and dermatan sulfate
(DS) glycosaminoglycans display variability of sulfation in
their constituent disaccharide repeats during chain elongation.
Since a large proportion of the extracellular matrix of the
central nervous system (CNS) is composed of proteoglycans,
CS/DS disaccharide degree and profile of sulfation play
important roles in the functional diversity of neurons, brain
development, and some of its pathological states. To
investigate the sulfation pattern of CS/DS structures expressed
in CNS, we introduced here a novel method based on an
advanced system encompassing fully automated chip nanoelectrospray
ionization (nanoESI) in the negative ion mode
and high capacity ion trap multistage mass spectrometry
(MS2-MS3) by collision-induced dissociation (CID). This
method, introduced here for the first time in glycomics of
brain glycosaminoglycans, was particularly applied to
structural investigation of disaccharides obtained by β-
elimination and digestion with chondroitin B and AC I lyase
of hybrid CS/DS chains from wild-type mouse brain.
Screening in the chip-MS mode of DS disaccharide fraction
resulting after depolymerization with chondroitin B lyase
revealed molecular ions assigned to monosulfated disaccharide
species having a composition of 4,5-Δ-[IdoA-GalNAc].
By optimized CID MS2-MS3, fragment ions supporting the
localization of sulfate ester group at C4 within GalNAc were
produced. Chip ESI MS profiling of CS disaccharide fraction
obtained by depolymerization of the same CS/DS chain
using chondroitin AC I lyase indicated the occurrence of
mono- and bisulfated 4,5-Δ-[GlcA-GalNAc]. The site of
oversulfation was determined by MS2-MS3, which provided
sequence patterns consistent with a rare GlcA-3-sulfate-
GalNAc-6-sulfate structural motif.

Cuvinte cheie: Condroitin/dermatansulfat.Creier de soarece.nano-ESI-HCIT-MS // Chondroitin/dermatan sulfate . Mouse brain . Fully automated chip-based nanoelectrospray . Ion trap mass spectrometry