Cereal Chem 58:534 - 537.  |  VIEW ARTICLE
Fractionation of Alcohol-Soluble Reduced Corn Glutelins on Phosphocellulose and Partial Characterization of Two Proline-Rich Fractions.

A. Esen, J. A. Bietz, J. W. Paulis, and J. S. Wall. Copyright 1981 by the American Association of Cereal Chemists, Inc. 

Alcohol-soluble reduced glutelin (ASG) from corn endosperm was fractionated by ion exchange chromatography on phosphocellulose. The ASG was dissolved in 0.01M Na-lactate buffer (pH 3.8) containing 60% isopropanol and 0.05M 2-mercaptoethanol and loaded onto phosphocellulose columns equilibrated with the same buffer. Columns were developed with a linear 0.0-0.5M NaCl gradient formed in the starting buffer, yielding two major overlapping peaks (each with shoulders) and four minor peaks. Each peak and subpeak was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by isoelectric focusing. Five fractions contained essentially a single size component. The two late-eluting fractions were further characterized. Each had the same molecular weight (27,500) and was heterogeneous when analyzed by isoelectric focusing. These fractions were partially soluble in water, rich in proline (26%) and glutamic acid (16%), and deficient in lysine (0.1%) and had threonine as the NH2-terminal residue. Polypeptides in these two fractions were similar in physicochemical characteristics to water-soluble ASG, previously described, and appeared to be coded by homologous genes.