Cereal Chem 62:276-279 | VIEW
Characterization of Oat (Avena sativa L.) Residual Proteins.
L. S. Robert, C. Nozzolillo, and I. Altosaar. Copyright 1985 by the American Association of Cereal Chemists, Inc.
Oat proteins remaining in the residue following the extraction of the albumins, globulins, and prolamins were studied. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) pattern observed for the residual proteins extracted with 7M urea and 2-mercaptoethanol (2-ME) was identical to that obtained with 1% SDS and 1% 2-ME, which is known to completely extract these proteins. The substitution of urea for SDS in solubilizing the oat residual proteins permitted their characterization by two- dimensional analysis (isoelectric focusing, Ph 3.5-10 followed by SDS PAGE). Most of the polypeptides of the residual fraction were found to comigrate with prolamins and especially globulins. However, minor polypeptide groups did not correspond to either prolamins or globulins and these minor proteins likely represent oat glutelins. Western blot analysis of the residual proteins using anti-oat 12S immunoglobulin G (IgG) demonstrated conclusively that the major proteins of the oat residue were globulins. These results support recent reports estimating globulin levels at 70-80% of the total oat proteins and consequently, glutelin levels of less than 10%.