REE BOUND PROTEINS IN NATURAL PLANT FERN DICRANOPTERIS-DICHITOMA BY MAA

Biochemical techniques, including pH variation, outsalting, ultracentr ifugation, gel filtration chromatography and electrophoresis, etc., ha ve been employed together with instrumental neutron activation analysi s (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern, Dicranopteris dichitoma. INAA was also used to ide ntify whether the proteins were bound firmly with REE,The results obta ined show that two REE bound proteins (REP-I and REP-II) have been sep arated. The molecular weight of REP-I on Sephadex G-200 gel column is about 8.10(5) Daltons and that of REP-II is less than 12,400 Daltons, respectively. However, SDS-PAGE of the two proteins shows that they ma inly have two protein subunits with MW 14,100 and 38,700 Daltons. They are probably conjugated proteins, glycoproteins with different glyco- units.