The cDNA derived primary structure of two distinct legumin A subunit precursors from field bean (Vicia fabaL.)

Legumin-like (US) storage globulins of legume seeds are oligomeric proteins consisting of six subunits (1). Each subunit is composed of two disulfide-linked polypeptide chains (2), both are primarily synthesized as one propolypeptide precursor (3). Two main, predominating legumin subunit groups (i.e. group A or I, and group B or IT) have been described (2, 3, 4, 5); here we present the first full-length coding sequence for field bean legumin type A. The sequences of clones LeA165 and LeA129 (Fig. 1) encode likely legumin Al and legumin A2 subunits, respectively (for classification, see (6)), thus representing subgroup heterogeneity.