SEED STORAGE PROTEINS IN FAGACEAE - SIMILARITY BETWEEN CASTANEA GLOBULINS AND QUERCUS GLUTELINS

Castanea sativa Mill. and C. crenata Lieb. and Zucc. store 11S globulins as major seed proteins while Quercus ilex L. and Q. robur L., also members of the Fagaceae family, accumulate glutelins. The structure of the 11S Castanea globulins, which is similar to the accepted model for this class of proteins, has been studied by different two-dimensional electrophoretic methods. The oligomer has a M(r) of 240 000-260 000, and the pairs of acidic-basic subunits, which form it, show great heterogeneity. The Quercus glutelins are made up of dimers linked by disulphide bridges, and their characteristics indicate a similarity to the subunits of 11S Castanea globulins. We suggest that, as in the case of rice glutelins, Quercus glutelins can also be considered legumin-like proteins.