Partial Characterization of a Vicilin-Like Glycoprotein from Seeds of Flowering Tobacco (Nicotiana sylvestris)‎

Abstract EN

A vicilin-like glycoprotein from the seeds of Nicotiana sylvestris, flowering tobacco, has been identified using nanoLC/ESI-MS/MS.

Sequences from a fragment of protein demonstrated homology with vicilins from other members of the Solanaceae family, notably potato (Solanum demissum).

Reducing and nonreducing SDS-PAGE analyses of the identified protein indicated that fragments resulting from in situ proteolytic processing are joined by intrachain disulphide bonds.

Staining with Con A lectin was specifically inhibited by mannose suggested the presence of N-linked glycosylation which was confirmed by carbohydrate compositional analysis of PVDF-bound protein subunits.

HPAEC-PAD analysis of the monosaccharides released from the glycoprotein by acid hydrolysis revealed glucosamine and mannose.

N-acetylglucosamine termination of attached oligosaccharides was further verified by inhibitable WGA lectin staining.

Immunostaining of PVDF-bound N.

sylvestris proteins with antibodies against G.

max total protein demonstrated cross-staining at masses corresponding to fragments from the proteolytically processed protein subunits.