Metabolite Profiling of Soybean Seed Extracts from Near-Isogenic Low and Normal Phytate Lines Using Orthogonal Separation Strategies.

Untargeted metabolomic profiling using liquid chromatography-mass spectrometry (LC-MS) was applied to lipid-depleted methanolic extracts of soybean seeds utilizing orthogonal chromatographic separations (reversed-phase and hydrophilic interaction) in both positive and negative ionization modes. Four near-isogenic lines (NILs) differing in mutations for two genes encoding highly homologous multidrug resistant proteins (MRPs) were evaluated. The double mutant exhibited a low phytate phenotype, whereas the other three NILs, the two single mutants and the wild type, did not.

A metabolomic assessment of NAC154 transcription factor overexpression in field grown poplar stem wood.

Several xylem-associated regulatory genes have been identified that control processes associated with wood formation in poplar. Prominent among these are the NAC domain transcription factors (NACs). Here, the putative involvement of Populus NAC154, a co-ortholog of the Arabidopsis gene SND2, was evaluated as a regulator of "secondary" biosynthetic processes in stem internode tissues by interrogating aqueous methanolic extracts from control and transgenic trees.

The exo-proteome and exo-metabolome of Nostoc punctiforme (Cyanobacteria) in the presence and absence of nitrate.

The ability of nitrogen-fixing filamentous Cyanobacteria to adapt to multiple environments comes in part from assessing and responding to external stimuli, an event that is initiated in the extracellular milieu. While it is known that these organisms produce numerous extracellular substances, little work has been done to characterize both the metabolites and proteins present under standard laboratory growth conditions. We have assessed the extracellular milieu of Nostoc punctiforme when grown in liquid culture in the presence and absence of a nitrogen source (nitrate).

Mass spectral analyses of corn stover prehydrolysates to assess conditioning processes.

Flow injection electrospray (FIE) and LC-tandem mass spectrometry techniques were used to characterize corn stover acid hydrolysates before and after overliming and ammonia conditioning steps. Analyses were performed on samples without fractionation (dilution only) in an effort provide an inventory of ionizable substances. Statistical evaluation of the results indicates that the ammonia-treated and crude hydrolysates were more similar to one another than any other pairing, with conditioning leading to a decrease in malate levels.