BEHAVIOR OF CONGLUTIN-GAMMA, A MAJOR LUPIN SEED PROTEIN DURING GERMINATION

Conglutin gamma is localized in the cotyledons of mature seeds of Lupi nus albus and L. luteus by immunocytochemistry (antibodies against whi te lupin conglutin gamma). It is detected in different types of protei n bodies, i.e. homogeneous and alveolated. Conglutin gamma is also pre sent in small quantities in the cytoplasm and around the lipid bodies. Immunoblots of globulins allow us to detect conglutin gamma in all sp ecies or varieties of lupin (antibodies against yellow lupin conglutin gamma). This result demonstrates a great homogeneity in the structure of the polypeptides of conglutin gamma. Concerning other legumes, the yellow lupin serum anti-conglutin gamma recognizes the Bg protein in soybean seeds and a similar protein in French bean seeds. As demonstra ted for Bg protein from soybeans, conglutin gamma is released by seeds of yellow lupin in hot water (60 degrees C). This happens more quickl y when seed coats are removed. New results concern usual conditions (2 5 degrees C) for imbibition and germination and demonstrate that congl utin gamma is also released in water. Moreover, conglutin gamma is con served in white lupin cotyledons after 15 days of germination. Polypep tide composition and western blots show no difference between congluti n gamma fraction from germinated seeds (up to 15 days) compared with d ry seeds.