title: Metabolic changes of Brassica rapa transformed with a bacterial isochorismate synthase gene.
abstract: Metabolome analysis by 1-dimensional proton nuclear magnetic resonance (¹H NMR) coupled with multivariate data analysis was carried out in Brassica rapa plants transformed with a gene encoding bacterial isochorismate synthase (ICS). Partial least square-discrimination analysis (PLS-DA) on selected signals suggested that the resonances that were dominant in the transgenic plants corresponded to a glucosinolate (neoglucobrassicin), phenylpropanoids (sinapoyl malate, feruloyl malate, caffeoyl malate), organic acids (succinic acid and fumaric acid) and sugars (α- and β-glucose). In contrast, amino acids alanine threonine, valine, leucine were dominant in the untransformed controls. In addition, HPLC data showed that the transgenic plant accumulated salicylic acid (SA) at significantly higher levels than the control plants, whereas the phylloquinone levels were not affected. The results suggest that the expression of the bacterial isochorismate synthase gene in B. rapa does not affect fluxes into pathways to other groups of secondary metabolites through competition for the same precursor. On the contrary, the biosynthesis of isochorismate-derived products (SA) seems to induce the competitive pathways via phenylalanine (phenylpropanoids) and tryptophan (IAA and indole glucosinolates).
authors: Division of Pharmacognosy, Section Metabolomics, Institute of Biology, Leiden University, Leiden, The Netherlands.
authors: Sanimah
authors: S
authors: Simoh
authors: Huub J M
authors: HJ
authors: Linthorst
authors: Alfons W M
authors: AW
authors: Lefeber
authors: Cornelis
authors: C
authors: Erkelens
authors: Hye Kyong
authors: HK
authors: Kim
authors: Young Hae
authors: YH
authors: Choi
authors: Robert
authors: R
authors: Verpoorte
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D029741:Brassica rapa / Q000235:genetics / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D019751:Intramolecular Transferases / Q000235:genetics / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008954:Models, Biological; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism*; D014170:Transformation, Genetic
chemical_list: D001426:Bacterial Proteins; D019751:Intramolecular Transferases; C058486:isochorismate synthase