title: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric behavior of succinoglycan monomers, dimers, and trimers isolated from Sinorhizobium meliloti 1021.
abstract: Low-molecular-weight (LMW) succinoglycans (monomers, dimers, and trimers) were isolated from Sinorhizobium meliloti 1021 and have been firstly investigated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) using 2,4,6-trihydroxyacetophenone (THAP) as an optimal matrix in the negative ion mode. The main fractions of LMW succinoglycans contain molecules assembled of octasaccharide subunits. MALDI-TOF mass spectra of the LMW succinoglycan monomers, the dimers, and the trimers showed the daughter ions resulting from the losses of the terminal galactose residues at the reducing ends, clearly indicating that the galactosyl linkages are more labile than the other glucosyl linkages. Furthermore, the losses of the acetyl groups as substituents rather than the succinyl and pyruvyl ester linkages by prompt fragmentation primarily occurred during MALDI-TOF analysis, suggesting the greater instability of acetyl linkages compared to pyruvyl and succinyl linkages.
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center & Center for Biotechnology Research in UBITA, Konkuk University, 1 Hwayang-dong Gwangjin-gu, Seoul 143-701, South Korea.
authors.forename: Chanho
authors.initials: C
authors.lastname: Kwon
authors.forename: Sanghoo
authors.initials: S
authors.lastname: Lee
authors.forename: Seunho
authors.initials: S
authors.lastname: Jung
mesh_terms: D002240:Carbohydrate Sequence; D019281:Dimerization; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification*; D016962:Sinorhizobium meliloti / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D011135:Polysaccharides, Bacterial; C056779:succinoglycan