Metabolic changes in transgenic maize mature seeds over-expressing the Aspergillus niger phyA2

Abstract

Non-targeted metabolomics analysis revealed only intended metabolic changes in transgenic maize over-expressing the Aspergillus niger phyA2. Genetically modified (GM) crops account for a large proportion of modern agriculture worldwide, raising increasingly the public concerns of safety. Generally, according to substantial equivalence principle, if a GM crop is demonstrated to be equivalently safe to its conventional species, it is supposed to be safe. In this study, taking the advantage of an established non-target metabolomic profiling platform based on the combination of UPLC-MS/MS with GC-MS, we compared the mature seed metabolic changes in transgenic maize over-expressing the Aspergillus niger phyA2 with its non-transgenic counterpart and other 14 conventional maize lines. In total, levels of nine out of identified 210 metabolites were significantly changed in transgenic maize as compared with its non-transgenic counterpart, and the number of significantly altered metabolites was reduced to only four when the natural variations were taken into consideration. Notably, those four metabolites were all associated with targeted engineering pathway. Our results indicated that although both intended and non-intended metabolic changes occurred in the mature seeds of this GM maize event, only intended metabolic pathway was found to be out of the range of the natural metabolic variation in the metabolome of the transgenic maize. Therefore, only when natural metabolic variation was taken into account, could non-targeted metabolomics provide reliable objective compositional substantial equivalence analysis on GM crops.

Metabolic characterization of human aqueous humor in the cataract progression after pars plana vitrectomy

“…Mev (MultiExperiment Viewer) 4.8 was employed for K-Medians clustering analysis. Significant changed metabolites were determined in partial least squares discriminant analysis (PLS-DA) model, followed by independent t tests (SPSS 17.0 software) as other studies and our previous study [ 15 – 19 ]. Metabolites with both VIP (variable importance in the projection) values in PLS-DA model more than 1 and p values (in t tests) less than 0.05 were considered to be significant.…”

Plant Metabolomics: An Indispensable System Biology Tool for Plant Science

“…If the variations between a GM crop and its non-GM counterpart parent lines fall in the range of natural variation, then it is considered to be safe at metabolic level [ 100 ]. However, for detecting unintended effects caused by genetic modification in GM crops, non-targeted metabolomics seemed to be more powerful than targeted metabolomics [ 101 ]. Nevertheless, the applications of non-targeted metabolomics in GM crops have not been validated and approved yet within the global regulatory framework for GM food safety assessment [ 97 ].…”

Fungal Phytase Production in Different Hosts: A Brief Review

“…Other types of plants have also been addressed for the expression of heterologous phytase. Plants such as Triticum aestivum, Chlamydomonas reinhardtii, Mature maize, Brassica napus and Zea mays L were used to express A. japonicas phytases reported by Abid, et al (2017) and A. niger studied by Rao, et al (2016), Rao J, et al (2013), and Drakakaki, et al (2005) [33][34][35][36][37] respectively.…”