Author
SONG, BO - Northeast Agricultural University | |
Oehrle, Nathan | |
LIU, SHANSHAN - Northeast Agricultural University | |
Krishnan, Hari |
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/11/2017 Publication Date: 1/17/2018 Citation: Song, B., Oehrle, N.W., Liu, S., Krishnan, H.B. 2018. Development and characterization of a soybean experimental line lacking the a' subunit of ß-conglycinin and G1, G2, and G4 glycinin. Journal of Agricultural and Food Chemistry. 66:432-439. https://doi.org/10.1021/acs.jafc.7b05011. DOI: https://doi.org/10.1021/acs.jafc.7b05011 Interpretive Summary: Soybean ranks among the eight most significant food allergens for humans. Soybean meal (SBM), the major by-product of soybean oil extraction, is the main protein source for poultry and swine diets globally. Previously several abundant soybean seed proteins have been identified as allergens that affect the growth of animals. At a time when US soybean meal is facing increasing competition from alternative feed ingredients and other soybean producing countries, it would benefit US soybean farmers if soybeans devoid of major allergens can be developed for both human food and animal feed. In this study, we have developed a soybean line that lack several important allergens by traditional breeding. Biochemical characterization revealed that this soybean line has improved protein quality. Information from this study will assist in the development of non-allergenic high yielding US soybean cultivars. Development of allergen-free soybeans will greatly enhance the nutritive value of soybean and increase the profitability of soybean growers. Technical Abstract: A soybean experimental line (BSH-3) devoid of a subset of seed storage proteins was developed by crossing a mutant donor line ‘HS99B’ with a Chinese cultivar ‘Dongnong47’ (DN47). One dimensional and high-resolution 2-D gel electrophoresis revealed the absence of G1 (A1aB2), G2 (A2B1a), and G4 (A5A4B3) glycinin and the a' subunit of ß-conglycinin in BSH-3 seeds. Despite the lack of these abundant seed proteins, BSH-3 seeds still accumulated 38% protein. BSH-3 seeds also accumulated high levels of free amino acids as compared to DN47 seeds, particularly arginine, and the amount of several essential amino acids were significantly elevated in BSH-3 seeds. Elevated accumulation of a and ß-subunit of ß-conglycinin, G5 glycinin, Kunitz trypsin inhibitor, and Bowman-Birk protease inhibitor indicated seed proteome rebalancing in BSH-3 seeds. Immunoblot analysis using sera from soybean allergic patients demonstrated the complete lack of a major allergen (a' subunit of ß-conglycinin) in BSH-3 seeds. However, elevated levels of other allergens were found in BSH-3 seeds due to proteome rebalancing. Transmission electron microscopy observation of mature seeds of BSH-3 revealed striking differences in the appearance of the protein storage vacuoles when compared to DN47. |