1H NMR and GC-MS metabolic fingerprinting of developmental stages of Rhizoctonia solani sclerotia

Abstract

Rhizoctonia solani AG-3 is a soilborne plant pathogen that forms resting vegetative structures called sclerotia. These compact structures are crucial to the pathogen's survival and pathogenesis. The metabolic changes occurring during sclerotia development were monitored using proton nuclear magnetic resonance ( 1 H NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS). The validation, discrimination, and the establishment of correlative relationships between metabolite signals were performed by principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The results of the analyses suggested that out of the 116 compounds that were simultaneously analyzed and compared using GC-MS, a-a-trehalose, D-glucose, 9-(Z)-octadecenoic and 9,12-octadecadienoic acids, xylitol, and glucitol were key metabolites that were highly dependent on the developmental stage of the sclerotia contributing to their discrimination and classification. Furthermore, the application of 1 H NMR and GC-MS metabolic fingerprinting on the same biological sample provided complementary information illustrating the value of this integrated approach in the study of metabolic changes in fungal structures.

Gas chromatography–mass spectrometry metabolite profiling of worker honey bee (Apis mellifera L.) hemolymph for the study of Nosema ceranae infection

“…Derivatization of dried samples was performed in two steps; first 80 lL of a methoxylamine hydrochloride solution (20 mg/mL in pyridine) was added, followed by the addition of 80 lL of MSTFA, as previously described (Aliferis and Jabaji, 2010). This derivatization system helps in reducing silylation artifacts, and is among the most commonly used for the derivatization of samples for GC/MS metabolomics studies (Fiehn and Kind, 2007;Kanani et al, 2008).…”

“…Analyses were performed using an Agilent 7890A gas chromatograph (GC) (Agilent Technologies Inc.) coupled with a 5975C series mass selective detector (MSD) and a 7693A series autosampler as previously described (Aliferis and Jabaji, 2010). Briefly, the analytical conditions were: temperature of injector 230°C; temperature of ion source 150°C; temperature of transfer line 230°C; initial temperature of the oven 70°C stable for 5 min, followed by a 5°C min À1 increase to 310°C and finally stable for 1 min.…”

“…The data matrix was subjected to multivariate analyses using the SIMCA-P+ v.12.0 software (Umetrics, MKS Instruments Inc.) as previously described (Aliferis and Jabaji, 2010). For the preliminary evaluation of data, principal component analysis (PCA) was performed.…”

On the use of Ethephon as abscising agent in cv. Crimson Seedless table grape production: Combination of Fruit Detachment Force, Fruit Drop and metabolomics

“…It is generally accepted that a single analytical technique seldom provides complete information on the metabolome and therefore a combined approach is desirable to gain a comprehensive view. In this respect, combination of NMR with HRMS is advisable as NMR easily provides information on molecules with relatively high concentration (typically, such molecules correspond to primary metabolites) while HRMS supplies precious information on molecules at low concentration (typically, such molecules constitute secondary metabolites) (Aliferis & Jabaji, 2010;Rizzuti et al, 2013). Recently, our research has been focused on the evaluation of the effects of various plantgrowth regulators on the metabolic profiles of table grapes.…”

Metabolomics in pesticide research and development: review and future perspectives

“…Thus, since one analytical platform alone cannot provide adequate information across a wide range of compounds, the strategic mating of different analytical platforms could greatly facilitate the overall analysis. The complementariness between NMR and MS as well as that between different MS platforms have been exploited in recent metabolomics studies (Atherton et al 2006;Moco et al 2008;Biais et al 2009;Leon et al 2009;McKelvie et al 2009;Aliferis and Jabaji 2010).…”