Legumin- and vicilin-like proteins from spores of the fernMatteuccia struthiopteris

Legumin- and vicilin-like proteins have been isolated from spores of the fern Matteuccia struthiopteris. Their relationship with seed legumin and vicilin was demonstrated by cross-reactivities of antibodies directed against respective storage globulins from Vicia faba as evidenced by Western blotting. The Matteuccia legumin-like protein was characterised as a 300-340 kDa holoprotein preferentially consisting of a 32 kDa α-chain and a 24 kDa β-chain. Patterns of limited proteolysis of the spore legumin-like protein and seed legumins were similar as well. In contrast to seed legumins, the Matteuccia legumin-like protein is devoid of disulfide bridges between α- and β-chains. A 52 kDa polypeptide of the Matteuccia vicilin-like protein, first detected by SDS gel electrophoresis, is probably encoded by a vicilin-like gene specifically expressed in Matteuccia struthiopteris spores (Shutov et al. 1998). The vicilin-like holoprotein was found to form a complex of 600 kDa apparent molecular mass, presumably composed of four vicilin-like trimers.