Albumin Storage Proteins in the Protein Bodies of Castor Bean

Abstract

Of the total protein in the protein bodies of castor bean (Ricinus communis L.), approximately 40% is represented by a group of closely related albumins localized in the matrix of the organelle. This group of albumins has a sedimentation value of 2S and is resolved into several proteins of MW around 12,000 daltons by sodium dodecyl sulfate-acrylamide gel electrophoresis. It has a high content of glutamate/glutamine and undergoes rapid degradation during the early stage of germination. In view of the abundance and ubiquitous occurrence of albumins in various seeds, albumins, in addition to globulins, glutelins and prolamines, are suggested to be important storage proteins in seeds.