PURIFICATION AND CHARACTERIZATION OF FERRITIN FROM ALFALFA SEEDS

Ferritin from alfalfa (Medicago sativa) seeds was isolated, purified, and characterized The apparent molecular mass of the native protein wa s found to be 560 kDa. Electrophoresis in denaturing gradient polyacry lamide-SDS gels revealed subunits of 28-26.5 kDa. The average iron cor es were 4 nm in diameter and contained about 1400 iron atoms, with an iron-to-phosphorus ratio of 4:1. N-terminal amino acid sequencing of t he 28 kDa subunit revealed close homology with other plant proteins. I mmunochemical analysis using polyclonal antibodies raised against pea- seed ferritin has confirmed, in agreement with previous reports, that plant proteins share common epitopes. (C) 1997 Elsevier Science Inc.