SELECTION OF AN EFFICIENT METHOD TO CHARACTERIZE SOYBEAN SEED PROTEINS FOR 2D AND MALDI-TOF ANALYSIS

Authors: Natarajan, Savithiry - Savi; XU, CHENPING - UNIVERSITY OF MARYLAND; Caperna, Thomas; Garrett, Wesley

Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2004
Publication Date: 3/15/2004
Citation: Natarajan, S.S., Xu, C., Caperna, T.J., Garrett, W.M. 2004. Selection of an efficient method to characterize soybean seed proteins for 2D and MALDI-TOF analysis [abstract]. American Society of Plant Biologists Annual Meeting. Abstract 710.

Interpretive Summary:

Technical Abstract: Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) is one of the most powerful proteomics tools for separation and quantification of proteins from a complex mixture. Several methods of 2D analysis of plant and seed proteins have been reported. In this study, we compared four different protein extraction methods, including trichloroacetic acid (TCA)/acetone, phenol, and lysis buffer with and without thiourea to determine the method that yielded the best separated soybean seed proteins by 2D-PAGE. The modified TCA/acetone method showed higher protein resolution, and spot intensity than the other three methods. In addition, several non-abundant proteins were strongly detected in samples extracted with the TCA/acetone method as compared to the other methods. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) analysis of trypsinized protein spots from 2D gels showed beta conglycinin with 3 subunits, glycinin with acidic and basic polypeptide chains, 2S albumin, globulin, dehydrin, trypsin inhibitor, and seed maturation proteins. These results indicate that the modified TCA/acetone method is an efficient and rapid method for 2D analysis of soybean seed proteins and is also suitable for MALDI-TOF analysis and identification of separated proteins.