|Natarajan, Savithiry - Savi
|KHAN, FAROOQ - University Of Maryland
|Luthria, Devanand - Dave
Submitted to: Journal of Data Mining in Genomics & Proteomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/11/2014
Publication Date: 9/18/2014
Citation: Natarajan, S.S., Khan, F., Luthria, D.L., Tucker, M.L., Song, Q., Garrett, W.M. 2014. A comparison of protein and phenolic compounds in seed from GMO and non-GMO soybean. Journal of Data Mining in Genomics & Proteomics. 5(3):161-169.
Interpretive Summary: Genetically modified (GM) crops have played a significant role in increasing the productivity and nutritional value of crops. Genetic modification of plants, in addition to producing the desired benefit, may evoke unintended traits that are not desirable, which is a major concern of consumers. We applied modern proteomic technologies and analyzed isoflavones, phenolic acids, and proteins in seeds of three genetically modified and non-modified control soybeans. The results showed no significant variation among control and modified soybeans. This study will allow scientists and regulatory agents to be better informed on how a genetically modified (transgenic) event, that is not expected to alter the metabolism or protein content of the plant, might unintentionally affect the nutritional value of the GM crop.
Technical Abstract: Soybean protein is a valuable and important component in human and animal diets. Approximately 94% of the soybean planted in the US is genetically modified (GM) to enhance quality and productivity. Since value-added traits are continuously being developed by genetic modification, it is important to determine if any unintended changes occur in GM soybean seeds. In this investigation, we have selected three different transgenic events (event 1, 2, and 3) with a single Agrobacterium tumefaciens T-DNA insert that included genes for a herbicide-resistance selectable gene(bar)and a beta-glucuronidase(GUS) reporter gene expressed using a double 35S Cauliflower Mosaic Virus(CaMV) promoter and a soybean polygalacturonase (Glyma12g01480) promoter, respectively. The transgenic lines and non-transgenic progenitor isoline (control) were used for both proteomic and phenolic compound analysis. Seed protein was extracted by TCA/acetone methodology and separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Out of approximately 1300 protein spots detected per protein extract, thirty spots were selected for further analysis based on software-determined differences in their relative abundance in the protein gels for the control and three events. The selected proteins were analyzed by mass spectrometry (MS) followed by a non-redundant search of the NCBI databases using the Mascot search engine. Subsequent analysis of variance (ANOVA) indicated that the abundance of only two of the thirty protein spots were significantly different at the 1% probability level. The two protein spots, an isoflavone reductase and a quinine oxidoreductase-like protein, in event 2 were significantly different from the control and the other two transgenic events. In addition to protein, two classes of phenolic compounds, isoflavonoids and phenolic acids, were analyzed by LC-MS. The results indicate no major differences in the amount or profile for either class of phenolic compounds in the control or three transgenic events.