Autori: C.Flangea, E.Sisu, D.G. Seidler, A.D. Zamfir

Editorial: Analytical Biochemistry, 420, p.155-, 2012.

Rezumat:

Biglycan (BGN) is a small proteoglycan that consists of a protein core containing leucine-rich repeat
regions and two glycosaminoglycan (GAG) chains of either chondroitin sulfate (CS) or dermatan sulfate
(DS) type. The development of novel, highly efficient analytical methods for structural identification of
BGN-derived CS/DS motifs, possibly implicated in biological events, is currently the focus of research.
In this work, an improved analytical method based on fully automated chip-nanoelectrospray ionization
(nanoESI) in conjunction with high-capacity ion trap (HCT) multistage mass spectrometry (MS) by
collision-induced dissociation (CID) was for the first time applied to BGN CS/DS oligosaccharide analysis.
The CS/DS chains were released from transfected 293 BGN by b-elimination. The chain was digested with
AC I lyase, and the resulting mixture was purified and subsequently separated by size exclusion chromatography
(SEC). Di- and tetrasaccharide fractions were pooled and characterized in detail using the
developed chip-nanoESI protocol. The chip-nanoESI MS profile in the negative ion mode revealed the
presence of under-, regularly, and oversulfated species in both di- and tetrasaccharide fractions. CID
MS2-MS3 yielded sequence patterns consistent with unusual oversulfated 4,5-D-GlcA(2S)-GalNAc(4S)
and 4,5-D-GlcA(2S)-GalNAc(6S)-IdoA(2S)-GalNAc(6S) motifs.

Cuvinte cheie: Biglycan Chondroitin/dermatan sulfate Fully automated chip-nanoelectrospray ionization High-capacity ion trap mass spectrometry Structural analysis