Submitted to: Journal of Plant Biochemistry and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2006
Publication Date: 9/18/2006
Citation: Natarajan, S.S., Xu, C., Bae, H., Caperna, T.J., Garrett, W.M. 2006. Proteomic analysis of allergen and antinutritional proteins in wild and cultivated soybean. Journal of Plant Biochemistry and Biotechnology. 15: 103-108. Interpretive Summary: Soybean is a rich and inexpensive source of proteins for humans and animals. However, some people have severe allergic reactions to soybean. Soybean ranks among the eight most significant food allergens. There are some data available that describe the natural variation in allergen proteins that occur in soybean. For a better understanding of the variation of allergen proteins that might be expected to occur in genetically modified (GM) soybeans, it is important to determine the natural variation of protein composition both in wild and cultivated soybeans that have been or may be used in conventional soybean breeding programs. Such variation would be considered as “naturally occurring” because it is not the result of genetic engineering. Therefore, we have conducted studies to determine and compare the composition of allergen and antinutritional proteins among wild and cultivated soybeans. To do this we used a “proteomics” approach, in which seed proteins are separated, identified and quantified using a device called a “mass spectrometer”. We observed that the wild soybean has more abundant allergenic and antinutritional proteins than the cultivated soybeans we examined. These results can be used to determine if the amounts of allergen and antinutritional proteins accumulated in GM soybeans exceed the level of these same proteins that naturally occur in non-GM soybean varieties.
Technical Abstract: In this study, profiles of allergen and antinutritional proteins both in wild (Glycine soja) and cultivated (Glycine max) soybean seeds were compared. We used two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) for the separation of proteins at two different pH ranges and applied a combined matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography mass spectrometry (LC-MS) analysis for the identification of proteins. Although overall distribution patterns of the allergen and antinutritional proteins Gly m Bd 60K ('-conglycinin), Gly m Bd 30K, Gly m Bd 28K, trypsin inhibitors, and lectin appeared similar, there was remarkable variation in the number and intensity of the protein spots between wild and cultivated genotypes. The wild genotype showed fifteen polypeptides of Gly m Bd 60K and three polypeptides of trypsin inhibitors. The cultivated genotypes showed twelve polypeptides of Gly m Bd 60K and two polypeptides of trypsin inhibitors. In contrast, the cultivated genotype showed two polypeptides of Gly m Bd 30K and three polypeptides of lectin and the wild type showed two and one polypeptides of Gly m Bd 30K and lectin, respectively. The same number of Gly m Bd 28K spots was observed in both genotypes. This is the first study reporting the comparative analysis of allergen and antinutritional protein in both wild and cultivated soybean genotypes using combined proteomic tools.