13C-labeling reveals non-conventional pathways providing carbon for hydroxy fatty acid synthesis in Physaria fendleri.

Physaria fendleri is a member of the Brassicaceae that produces in its embryos hydroxy fatty acids, constituents of oils that are very valuable and widely used by industry for cosmetics, lubricants, biofuels, etc. Free of toxins and rich in hydroxy fatty acids, Physaria provides a promising alternative to imported castor oil and is on the verge of being commercialized. This study aims to identify important biochemical step(s) for oil synthesis in Physaria, which may serve as target(s) for future crop improvement. To advance towards this goal, the endosperm composition was analysed by LC-MS/MS to develop and validate culture conditions that mimic the development of the embryos in planta. Using developing Physaria embryos in culture and 13C-labeling, our studies revealed that: (i) Physaria embryos metabolize carbon into biomass with an efficiency significantly lower than other photosynthetic embryos; (ii) the plastidic malic enzyme provides 42% of the pyruvate used for de novo fatty acid synthesis, which is the highest measured so far in developing 'green' oilseed embryos; and (iii) Physaria uses non-conventional pathways to channel carbon into oil, namely the Rubisco shunt, which fixes CO2 released in the plastid, and the reversibility of isocitrate dehydrogenase, which provides additional carbon for fatty acid elongation.

Time-resolved systems analysis of the induction of high photosynthetic capacity in Arabidopsis during acclimation to high light.

Induction of high photosynthetic capacity is a key acclimation response to high light (HL) for many herbaceous dicot plants; however, the signaling pathways that control this response remain largely unknown. Here, a systems biology approach was utilized to characterize the induction of high photosynthetic capacity in strongly and weakly acclimating Arabidopsis thaliana accessions. Plants were grown for 5 wk in a low light (LL) regime, and time-resolved photosynthetic physiological, metabolomic, and transcriptomic responses were measured during subsequent exposure to HL. The induction of high nitrogen (N) assimilation rates early in the HL shift was strongly predictive of the induction of photosynthetic capacity later in the HL shift. Accelerated N assimilation rates depended on the mobilization of existing organic acid (OA) reserves and increased de novo OA synthesis during the induction of high photosynthetic capacity. Enhanced sucrose biosynthesis capacity increased in tandem with the induction of high photosynthetic capacity, and increased starch biosynthetic capacity was balanced by increased starch catabolism. This systems analysis supports a model in which the efficient induction of N assimilation early in the HL shift begins the cascade of events necessary for the induction of high photosynthetic capacity acclimation in HL.

Elevated CO2 increases biomass of Sorghum bicolor green prop roots under drought conditions via soluble sugar accumulation and photosynthetic activity.

Elevated [CO2 ] (E[CO2 ]) mitigates agricultural losses of C4 plants under drought. Although several studies have described the molecular responses of the C4 plant species Sorghum bicolor during drought exposure, few have reported the combined effects of drought and E[CO2 ] (E[CO2 ]/D) on the roots. A previous study showed that, among plant organs, green prop roots (GPRs) under E[CO2 ]/D presented the second highest increase in biomass after leaves compared with ambient [CO2 ]/D. GPRs are photosynthetically active and sensitive to drought. To understand which mechanisms are involved in the increase in biomass of GPRs, we performed transcriptome analyses of GPRs under E[CO2 ]/D. Whole-transcriptome analysis revealed several pathways altered under E[CO2 ]/D, among which photosynthesis was strongly affected. We also used previous metabolome data to support our transcriptome data. Activities associated with photosynthesis and central metabolism increased, as seen by the upregulation of photosynthesis-related genes, a rise in glucose and polyol contents, and increased contents of chlorophyll a and carotenoids. Protein-protein interaction networks revealed that proliferation, biogenesis, and homeostasis categories were enriched and contained mainly upregulated genes. The findings suggest that the previously reported increase in GPR biomass of plants grown under E[CO2 ]/D is mainly attributed to glucose and polyol accumulation, as well as photosynthesis activity and carbon provided by respiratory CO2 refixation. Our findings reveal that an intriguing and complex metabolic process occurs in GPRs under E[CO2 ]/D, showing the crucial role of these organs in plant drought /tolerance.

A lipidomics platform to analyze the fatty acid compositions of non-polar and polar lipid molecular species from plant tissues: Examples from developing seeds and seedlings of pennycress (Thlaspi arvense).

The lipidome comprises the total content of molecular species of each lipid class, and is measured using the analytical techniques of lipidomics. Many liquid chromatography-mass spectrometry (LC-MS) methods have previously been described to characterize the lipidome. However, many lipidomic approaches may not fully uncover the subtleties of lipid molecular species, such as the full fatty acid (FA) composition of certain lipid classes. Here, we describe a stepwise targeted lipidomics approach to characterize the polar and non-polar lipid classes using complementary LC-MS methods. Our "polar" method measures 260 molecular species across 12 polar lipid classes, and is performed using hydrophilic interaction chromatography (HILIC) on a NH2 column to separate lipid classes by their headgroup. Our "non-polar" method measures 254 molecular species across three non-polar lipid classes, separating molecular species on their FA characteristics by reverse phase (RP) chromatography on a C30 column. Five different extraction methods were compared, with an MTBE-based extraction chosen for the final lipidomics workflow. A state-of-the-art strategy to determine and relatively quantify the FA composition of triacylglycerols is also described. This lipidomics workflow was applied to developing, mature, and germinated pennycress seeds/seedlings and found unexpected changes among several lipid molecular species. During development, diacylglycerols predominantly contained long chain length FAs, which contrasted with the very long chain FAs of triacylglycerols in mature seeds. Potential metabolic explanations are discussed. The lack of very long chain fatty acids in diacylglycerols of germinating seeds may indicate very long chain FAs, such as erucic acid, are preferentially channeled into beta-oxidation for energy production.

Dynamic nutrient acquisition from a hydrated apoplast supports biotrophic proliferation of a bacterial pathogen of maize.

Plant pathogens perturb their hosts to create environments suitable for their proliferation, including the suppression of immunity and promotion of water and nutrient availability. Although necrotrophs obtain water and nutrients by disrupting host-cell integrity, it is unknown whether hemibiotrophs, such as the bacterial pathogen Pantoea stewartii subsp. stewartii (Pnss), actively liberate water and nutrients during the early, biotrophic phase of infection. Here, we show that water and metabolite accumulation in the apoplast of Pnss-infected maize leaves precedes the disruption of host-cell integrity. Nutrient acquisition during this biotrophic phase is a dynamic process; the partitioning of metabolites into the apoplast rate limiting for their assimilation by proliferating Pnss cells. The formation of a hydrated and nutritive apoplast is driven by an AvrE-family type III effector, WtsE. Given the broad distribution of AvrE-family effectors, this work highlights the importance of actively acquiring water and nutrients for the proliferation of phytopathogenic bacteria during biotrophy.

Metabolite shift in Medicago truncatula occurs in phosphorus deprivation.

Symbiotic nitrogen (N) fixation entails successful interaction between legume hosts and rhizobia that occur in specialized organs called nodules. N-fixing legumes have a higher demand for phosphorus (P) than legumes grown on mineral N. Medicago truncatula is an important model plant for characterization of effects of P deficiency at the molecular level. Hence, a study was carried out to address the alteration in metabolite levels of M. truncatula grown aeroponically and subjected to 4 weeks of P stress. First, GC-MS-based untargeted metabolomics initially revealed changes in the metabolic profile of nodules, with increased levels of amino acids and sugars and a decline in amounts of organic acids. Subsequently, LC-MS/MS was used to quantify these compounds including phosphorylated metabolites in the whole plant. Our results showed a drastic reduction in levels of organic acids and phosphorylated compounds in -P leaves, with a moderate reduction in -P roots and nodules. Additionally, sugars and amino acids were elevated in the whole plant under P deprivation. These findings provide evidence that N fixation in M. truncatula is mediated through a N feedback mechanism that in parallel is related to carbon and P metabolism.

A metabolomic platform to identify and quantify polyphenols in coffee and related species using liquid chromatography mass spectrometry.

Introduction: Products of plant secondary metabolism, such as phenolic compounds, flavonoids, alkaloids, and hormones, play an important role in plant growth, development, stress resistance. The plant family Rubiaceae is extremely diverse and abundant in Central America and contains several economically important genera, e.g. Coffea and other medicinal plants. These are known for the production of bioactive polyphenols (e.g. caffeine and quinine), which have had major impacts on human society. The overall goal of this study was to develop a high-throughput workflow to identify and quantify plant polyphenols. Methods: First, a method was optimized to extract over 40 families of phytochemicals. Then, a high-throughput metabolomic platform has been developed to identify and quantify 184 polyphenols in 15 min. Results: The current metabolomics study of secondary metabolites was conducted on leaves from one commercial coffee variety and two wild species that also belong to the Rubiaceae family. Global profiling was performed using liquid chromatography high-resolution time-of-flight mass spectrometry. Features whose abundance was significantly different between coffee species were discriminated using statistical analysis and annotated using spectral databases. The identified features were validated by commercially available standards using our newly developed liquid chromatography tandem mass spectrometry method. Discussion: Caffeine, trigonelline and theobromine were highly abundant in coffee leaves, as expected. Interestingly, wild Rubiaceae leaves had a higher diversity of phytochemicals in comparison to commercial coffee: defense-related molecules, such as phenylpropanoids (e.g., cinnamic acid), the terpenoid gibberellic acid, and the monolignol sinapaldehyde were found more abundantly in wild Rubiaceae leaves.

The Evolution of Leaf Function during Development Is Reflected in Profound Changes in the Metabolic Composition of the Vacuole.

During its development, the leaf undergoes profound metabolic changes to ensure, among other things, its growth. The subcellular metabolome of tomato leaves was studied at four stages of leaf development, with a particular emphasis on the composition of the vacuole, a major actor of cell growth. For this, leaves were collected at different positions of the plant, corresponding to different developmental stages. Coupling cytology approaches to non-aqueous cell fractionation allowed to estimate the subcellular concentrations of major compounds in the leaves. The results showed major changes in the composition of the vacuole across leaf development. Thus, sucrose underwent a strong allocation, being mostly located in the vacuole at the beginning of development and in the cytosol at maturity. Furthermore, these analyses revealed that the vacuole, rather rich in secondary metabolites and sugars in the growth phases, accumulated organic acids thereafter. This result suggests that the maintenance of the osmolarity of the vacuole of mature leaves would largely involve inorganic molecules.

Targeted Metabolic Profiles of the Leaves and Xylem Sap of Two Sugarcane Genotypes Infected with the Vascular Bacterial Pathogen Leifsonia xyli subsp. xyli.

Ratoon stunt (RS) is a worldwide disease that reduces biomass up to 80% and is caused by the xylem-dwelling bacterium Leifsonia xyli subsp. xyli. This study identified discriminant metabolites between a resistant (R) and a susceptible (S) sugarcane variety at the early stages of pathogen colonization (30 and 120 days after inoculation-DAI) by untargeted and targeted metabolomics of leaves and xylem sap using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. Bacterial titers were quantified in sugarcane extracts at 180 DAI through real-time polymerase chain reaction. Bacterial titers were at least four times higher on the S variety than in the R one. Global profiling detected 514 features in the leaves and 68 in the sap, while 119 metabolites were quantified in the leaves and 28 in the sap by targeted metabolomics. Comparisons between mock-inoculated treatments indicated a greater abundance of amino acids in the leaves of the S variety and of phenolics, flavonoids, and salicylic acid in the R one. In the xylem sap, fewer differences were detected among phenolics and flavonoids, but also included higher abundances of the signaling molecule sorbitol and glycerol in R. Metabolic changes in the leaves following pathogen inoculation were detected earlier in R than in S and were mostly related to amino acids in R and to phosphorylated compounds in S. Differentially represented metabolites in the xylem sap included abscisic acid. The data represent a valuable resource of potential biomarkers for metabolite-assisted selection of resistant varieties to RS.

Differential Metabolic Responses Caused by the Most Important Insect Pest of Coffee Worldwide, the Coffee Berry Borer (Hypothenemus hampei).

The world's coffee supply is threatened by the coffee berry borer, Hypothenemus hampei, the most destructive pest affecting coffee production and quality. This study hypothesized that coffee berry borer infestation induces distinct metabolic responses in the green coffee seeds of Coffea arabica and Coffea canephora (robusta). A targeted metabolomics approach was conducted using liquid chromatography tandem mass spectrometry to quantify intracellular metabolites in infested and uninfested arabica and robusta green seeds. In parallel, the seed biomass content and composition were assessed for the same conditions. Coffee berry borer attack induced increases in the levels of chlorogenic acids in arabica seeds, whereas organic acids and sugar alcohols were more abundant in infested robusta seeds. Most importantly, a set of compounds was identified as biomarkers differentiating the metabolic response of these taxa to the coffee berry borer.

Non-conventional pathways enable pennycress (Thlaspi arvense L.) embryos to achieve high efficiency of oil biosynthesis.

Pennycress (Thlaspi arvense L.) accumulates oil up to 35% of the total seed biomass, and its overall fatty acid composition is suitable for aviation fuel. However, for this plant to become economically viable, its oil production needs to be improved. In vivo culture conditions that resemble the development of pennycress embryos in planta were developed based on the composition of the liquid endosperm. Then, substrate uptake rates and biomass accumulation were measured from cultured pennycress embryos, revealing a biosynthetic efficiency of 93%, which is one of the highest in comparison with other oilseeds to date. Additionally, the ratio of carbon in oil to CO2 indicated that non-conventional pathways are likely to be responsible for such a high carbon conversion efficiency. To identify the reactions enabling this phenomenon, parallel labeling experiments with 13C-labeled substrates were conducted in pennycress embryos. The main findings of these labeling experiments include: (i) the occurrence of the oxidative reactions of the pentose phosphate pathway in the cytosol; (ii) the reversibility of isocitrate dehydrogenase; (iii) the operation of the plastidic NADP-dependent malic enzyme; and (iv) the refixation of CO2 by Rubisco. These reactions are key providers of carbon and reductant for fatty acid synthesis and elongation.

Liquid Chromatography Tandem Mass Spectrometry Quantification of 13C-Labeling in Sugars.

Subcellular compartmentation has been challenging in plant 13C-metabolic flux analysis. Indeed, plant cells are highly compartmented: they contain vacuoles and plastids in addition to the regular organelles found in other eukaryotes. The distinction of reactions between compartments is possible when metabolites are synthesized in a particular compartment or by a unique pathway. Sucrose is an example of such a metabolite: it is specifically produced in the cytosol from glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P). Therefore, determining the 13C-labeling in the fructosyl and glucosyl moieties of sucrose directly informs about the labeling of cytosolic F6P and G6P, respectively. To date, the most commonly used method to monitor sucrose labeling is by nuclear magnetic resonance, which requires substantial amounts of biological sample. This study describes a new methodology that accurately measures the labeling in free sugars using liquid chromatography tandem mass spectrometry (LC-MS/MS). For this purpose, maize embryos were pulsed with [U-13C]-fructose, intracellular sugars were extracted, and their time-course labeling was analyzed by LC-MS/MS. Additionally, extracts were enzymatically treated with hexokinase to remove the soluble hexoses, and then invertase to cleave sucrose into fructose and glucose. Finally, the labeling in the glucosyl and fructosyl moieties of sucrose was determined by LC-MS/MS.

High Flux Through the Oxidative Pentose Phosphate Pathway Lowers Efficiency in Developing Camelina Seeds.

Many seeds are green during development, and light has been shown to play a role in the efficiency with which maternally supplied substrates are converted into storage compounds. However, the effects of light on the fluxes through central metabolism that determine this efficiency are poorly understood. Here, we used metabolic flux analysis to determine the effects of light on central metabolism in developing embryos of false flax (Camelina sativa). Metabolic efficiency in C. sativa is of interest because, despite its growing importance as a model oilseed and engineering target and its potential as a biofuel crop, its yields are lower than other major oilseed species. Culture conditions under which steady-state growth and composition of developing embryos match those in planta were used to quantify substrate uptake and respiration rates. The carbon conversion efficiency (CCE) was 21% ± 3% in the dark and 42% ± 4% under high light. Under physiological illumination, the CCE (32% ± 2%) was substantially lower than in green and nongreen oilseeds studied previously. 13C and 14C isotopic labeling experiments were used together with computer-aided modeling to map fluxes through central metabolism. Fluxes through the oxidative pentose phosphate pathway (OPPP) were the principal source of CO2 production and strongly negatively correlated with CCE across light levels. OPPP fluxes were greatly in excess of demand for NAD(P)H for biosynthesis and larger than those measured in other systems. Excess reductant appears to be dissipated via cyanide-insensitive respiration. OPPP enzymes therefore represent a potential target for increasing efficiency and yield in C. sativa.

A Combined Metabolomics and Fluxomics Analysis Identifies Steps Limiting Oil Synthesis in Maize Embryos.

Enhancing fatty acid synthesis (FAS) in maize (Zea mays) has tremendous potential nutritional and economic benefits due to the rapidly growing demand for vegetable oil. In maize kernels, the endosperm and the embryo are the main sites for synthesis and accumulation of starch and oil, respectively. So far, breeding efforts to achieve elevated oil content in maize have resulted in smaller endosperms and therefore lower yield. Directly changing their carbon metabolism may be the key to increasing oil content in maize kernels without affecting yield. To test this hypothesis, the intracellular metabolite levels were compared in maize embryos from two different maize lines, ALEXHO S K SYNTHETIC (Alex) and LH59, which accumulate 48% and 34% of oil, respectively. Comparative metabolomics highlighted the metabolites and pathways that were active in the embryos and important for oil production. The contribution of each pathway to FAS in terms of carbon, reductant, and energy provision was assessed by measuring the carbon flow through the metabolic network (13C-metabolic flux analysis) in developing Alex embryos to build a map of carbon flow through the central metabolism. This approach combined mathematical modeling with biochemical quantification to identify metabolic bottlenecks in FAS in maize embryos. This study describes a combination of innovative tools that will pave the way for controlling seed composition in important food crops.

Quantification of Tau Protein Lysine Methylation in Aging and Alzheimer's Disease.

Tau is a microtubule-associated protein that normally interacts in monomeric form with the neuronal cytoskeleton. In Alzheimer's disease, however, it aggregates to form the structural component of neurofibrillary lesions. The transformation is controlled in part by age- and disease-associated post-translational modifications. Recently we reported that tau isolated from cognitively normal human brain was methylated on lysine residues, and that high-stoichiometry methylation depressed tau aggregation propensity in vitro. However, whether methylation stoichiometry reached levels needed to influence aggregation propensity in human brain was unknown. Here we address this problem using liquid chromatography-tandem mass spectrometry approaches and human-derived tau samples. Results revealed that lysine methylation was present in soluble tau isolated from cognitively normal elderly cases at multiple sites that only partially overlapped with the distributions reported for cognitively normal middle aged and AD cohorts, and that the quality of methylation shifted from predominantly dimethyl-lysine to monomethyl-lysine with aging and disease. However, bulk mol methylation/mol tau stoichiometries never exceeded 1 mol methyl group/mol tau protein. We conclude that lysine methylation is a physiological post-translational modification of tau protein that changes qualitatively with aging and disease, and that pharmacological elevation of tau methylation may provide a means for protecting against pathological tau aggregation.

Beyond the wall: High-throughput quantification of plant soluble and cell-wall bound phenolics by liquid chromatography tandem mass spectrometry.

Plants accumulate several thousand of phenolic compounds, including lignins and flavonoids, which are mainly synthesized through the phenylpropanoid pathway, and play important roles in plant growth and adaptation. A novel high-throughput ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was established to quantify the levels of 19 flavonoids and 15 other phenolic compounds, including acids, aldehydes, and alcohols. The chromatographic separation was performed in 10 min, allowing for the resolution of isomers such as 3-, 4-, and 5-chlorogenic acids, 4-hydroxybenzoic and salicylic acids, isoorientin and orientin, and luteolin and kaempferol. The linearity range for each compound was found to be in the low fmol to the high pmol. Furthermore, this UHPLC-MS/MS approach was shown to be very sensitive with limits of detection between 1.5 amol to 300 fmol, and limits of quantification between 5 amol to 1000 fmol. Extracts from maize seedlings were used to assess the robustness of the method in terms of recovery efficiency, matrix effect, and accuracy. The biological matrix did not suppress the signal for 32 out of the 34 metabolites under investigation. Additionally, the majority of the analytes were recovered from the biological samples with an efficiency above 75%. All flavonoids and other phenolic compounds had an intra- and inter-day accuracy within a ±20% range, except for coniferyl alcohol and vanillic acid. Finally, the quantification of flavonoids, free and cell wall-bound phenolics in seedlings from two maize lines with contrasting phenolic content was successfully achieved using this methodology.

A liquid chromatography tandem mass spectroscopy approach for quantification of protein methylation stoichiometry.

Post-translational modifications are biologically important and wide-spread modulators of protein function. Although methods for detecting the presence of specific modifications are becoming established, approaches for quantifying their mol modification/mol protein stoichiometry are less well developed. Here we introduce a ratiometric, label-free, targeted liquid chromatography tandem mass spectroscopy-based method for estimating Lys and Arg methylation stoichiometry on post-translationally modified proteins. Methylated Lys and Arg were detected with limits of quantification at low fmol and with linearity extending from 20 to 5000 fmol. This level of sensitivity allowed estimation of methylation stoichiometry from microgram quantities of various proteins, including those derived from either recombinant or tissue sources. The method also disaggregated total methylation stoichiometry into its elementary mono-, di-, and tri-methylated residue components. In addition to being compatible with kinetic experiments of protein methylation, the approach will be especially useful for characterizing methylation states of proteins isolated from cells and tissues.

Combining semi-synthesis with plant and microbial biocatalysis: new frontiers in producing a chemical arsenal against cancer.

Natural products (NPs) that exhibit anticancer activities are frequently not potent enough to be used clinically as therapeutics. Semi-synthesis and metabolic engineering are promising approaches for producing more efficacious derivatives of anticancer NPs (ACNPs), but each technique alone can be inefficient at obtaining specific ACNP derivatives that may be suspected to have enhanced anticancer activity. Here, we demonstrate that the methods of semi-synthesis and biocatalysis can be used as modules in succession and in different combinations to produce 6,8-dibromogenkwanin, a derivative of the ACNP apigenin. Further, we demonstrated that soybean seed coats can be used as a biocatalyst to convert brominated flavonoids into multiple derivatives. A strength of the combinatorial (bio)synthesis approach was that the order of the modules could be rearranged to increase the yield of the desired product. At lower treatment concentration (5 µM), 6,8-dibromogenkwanin exhibited enhanced antiproliferative activities against HT-29 colorectal adenocarcinoma cancer cells under normoxic and hypoxic conditions compared to its ACNP precursors, but not at higher concentrations. Dose-response analyses suggested that dibromogenkwanin had a distinct mode-of-action compared to apigenin. Thus, this proof-of-concept paper demonstrates combinatorial (bio)synthesis as an approach that can be used to produce novel chemistries for anticancer research.

The gluconate shunt is an alternative route for directing glucose into the pentose phosphate pathway in fission yeast.

Glycolysis and the pentose phosphate pathway both play a central role in the degradation of glucose in all domains of life. Another metabolic route that can facilitate glucose breakdown is the gluconate shunt. In this shunt glucose dehydrogenase and gluconate kinase catalyze the two-step conversion of glucose into the pentose phosphate pathway intermediate 6-phosphogluconate. Despite the presence of these enzymes in many organisms, their only established role is in the production of 6-phosphogluconate for the Entner-Doudoroff pathway. In this report we performed metabolic profiling on a strain of Schizosaccharomyces pombe lacking the zinc-responsive transcriptional repressor Loz1 with the goal of identifying metabolic pathways that were altered by cellular zinc status. This profiling revealed that loz1Δ cells accumulate higher levels of gluconate. We show that the altered gluconate levels in loz1Δ cells result from increased expression of gcd1 By analyzing the activity of recombinant Gcd1 in vitro and by measuring gluconate levels in strains lacking enzymes of the gluconate shunt we demonstrate that Gcd1 encodes a novel NADP+-dependent glucose dehydrogenase that acts in a pathway with the Idn1 gluconate kinase. We also find that cells lacking gcd1 and zwf1, which encode the first enzyme in the pentose phosphate pathway, have a more severe growth phenotype than cells lacking zwf1 We propose that in S. pombe Gcd1 and Idn1 act together to shunt glucose into the pentose phosphate pathway, creating an alternative route for directing glucose into the pentose phosphate pathway that bypasses hexokinase and the rate-limiting enzyme glucose-6-phosphate dehydrogenase.

Impact of Environment on the Biomass Composition of Soybean (Glycine max) seeds.

Factors including genetics, fertilization, and climatic conditions, can alter the biomass composition of soybean seeds, consequently impacting their market value and usage. This study specifically determined the content of protein and oil, as well as the composition of proteinogenic amino acids and fatty acids in seeds from 10 diverse soybean cultivars grown in four different sites. The results highlighted that different environments produce a different composition for the 10 cultivars under investigation. Specifically, the levels of oleic and linoleic acids, important contributors to oil stability, were negatively correlated. Although the protein and oil contents were higher in some locations, their "quality" was lower in terms of composition of essential amino acids and oleic acid, respectively. Finally, proteinogenic histidine and glutamate were the main contributors to the separation between Central and Northern growing sites. Taken together, these results can guide future breeding and engineering efforts aiming to develop specialized soybean lines.