Occurrence of Free N-Glycans in Pea (Pisum sativum, L) Seedlings†

Abstract

Free N-glycans have been found in pea seedlings. These free N-glycans were coupled with 2-aminopyridine and purified by gel filtration, Con Α-Sepharose affinity chromatography, and size fractionation HPLC. These structures of pyridylaminated free N-glycans were analyzed by exomannosidase digestions and ion- spray tandem mass spectrometry. The structural analyses showed that the several oligomannose-type sugar chains having one GlcNAc residue at the reducing-end side occur in the seedlings, suggesting the endo-β-N-acetylgIucosaminidase PS [Y. Kimura et al., Biosci. Biotech. Biochem., 60, 228–232 (1996)] should be involved in the release of oligomannose-type N-glycans from the storage glycoproteins [Y. Kimura et al., Biosci. Biotech. Biochem., 60, 1841–1850 (1996)] during the germination of pea seeds. © 1997, Taylor & Francis Group, LLC. All rights reserved.