Mass spectrometric analysis of neutral and anionic N-glycans from a Dictyostelium discoideum model for human congenital disorder of glycosylation CDG IL.
J Proteome Res
; 12(3): 1173-87, 2013 Mar 01.
Article
en En
| MEDLINE
| ID: mdl-23320427
ABSTRACT
The HL241 mutant strain of the cellular slime mold Dictyostelium discoideum is a potential model for human congenital disorder of glycosylation type IL (ALG9-CDG) and has been previously predicted to possess a lower degree of modification of its N-glycans with anionic moieties than the parental wild-type. In this study, we first showed that this strain has a premature stop codon in its alg9 mannosyltransferase gene compatible with the occurrence of truncated N-glycans. These were subject to an optimized analytical workflow, considering that the mass spectrometry of acidic glycans often presents challenges due to neutral loss and suppression effects. Therefore, the protein-bound N-glycans were first fractionated, after serial enzymatic release, by solid phase extraction. Then primarily single glycan species were isolated by mixed hydrophilic-interaction/anion-exchange or reversed-phase HPLC and analyzed using chemical and enzymatic treatments and MS/MS. We show that protein-linked N-glycans of the mutant are of reduced size as compared to those of wild-type AX3, but still contain core α1,3-fucose, intersecting N-acetylglucosamine, bisecting N-acetylglucosamine, methylphosphate, phosphate, and sulfate residues. We observe that a single N-glycan can carry up to four of these six possible modifications. Due to the improved analytical procedures, we reveal fuller details regarding the N-glycomic potential of this fascinating model organism.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Polisacáridos
/
Trastornos Congénitos de Glicosilación
/
Dictyostelium
/
Espectrometría de Masas en Tándem
/
Modelos Biológicos
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
J Proteome Res
Asunto de la revista:
BIOQUIMICA
Año:
2013
Tipo del documento:
Article
País de afiliación:
Austria