Analysis of plant glycoproteins by matrix-assisted laser desorption ionisation mass spectrometry: Application to the N-glycosylation analysis of bean phytohemagglutinin

• Published in: Plant physiology and biochemistry 1999-04, Vol.37 (4), p.319-325
• Main Authors: Bardor, Muriel, Loutelier-Bourhis, Corinne, Marvin, Laure, Cabanes-Macheteau, Marion, Lange, Catherine, Lerouge, Patrice, Faye, Loïc
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Economic plant physiology; Fundamental and applied biological sciences. Psychology; MALDI-TOF; Metabolism; N-glycosylation; Nitrogen metabolism; Nitrogen metabolism and other ones (excepting carbon metabolism); Nutrition. Photosynthesis. Respiration. Metabolism; Phaseolus vulgaris; phytohemagglutinin; Plant physiology and development
• ISSN: 0981-9428; 1873-2690
• DOI: 10.1016/S0981-9428(99)00138-2

Matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) spectrometry is a recently developed soft ionisation mass spectrometry technique which appears as a highly efficient tool for the N-glycosylation analysis of glycoproteins. The potentiality of this analytical technique is illustrated through the analysis of the N-glycosylation of the isolectin L of bean phytohemagglutinin (PHA-L). The analysis was carried out on the native PHA-L as well as on the N-glycans released from this lectin. Furthermore, the two glycopeptides containing the potential N-glycosylation sites prepared by proteolytic cleavage of PHA-L and purified by HPLC were analysed by MALDI-TOF. This study has confirmed that PHA-L is N-glycosylated by two populations of oligosaccharides, high-mannose-type N-glycans and paucimannosidic-type N-glycans, located on Asn-12 and Asn-60, respectively, and has pointed out the microheterogeneity of the glycans N-linked on both Asn residues.