Soybean seeds have low levels of methionine, making nutritional enhancement an area of interest for scientists around the globe. Several strategies are being adopted to increase methionine content in soybean seeds. One such a strategy is the transgenic approach, where a gene of interest is introduced into the genome to increase methionine content. Toward this goal, an 18 kDa maize gene (δ-zein) had been introduced into soybean, resulting in significantly increased methionine content in the seed. In this investigation, we compared the protein profile of the transgenic soybean with the wild type to determine if transformation resulted in unintended effects, such as an increase in antinutritional proteins. We identified more than 5,333 different proteins, of which 28 exhibited significantly increased and 13 showed significantly decreased content in the transgenic soybean. The quantified proteins were mapped onto global metabolic pathways. Transgenic soybeans showed changes in protein and enzyme content associated with carbohydrate and methionine metabolism, with minimal impact on other proteins, including allergens and anti-nutritional proteins, making this variety of interest for the protein-based food industry.
Islam et al. (Mon,) studied this question.