Biosynthesis Of Metabolites In Plants Research Articles

Metabolic signatures altered by in vitro temperature stress in Ajuga bracteosa Wall. ex. Benth.

To elucidate how biosynthesis of plant metabolites is affected by temperature, metabolite profiles from in vitro regenerated plants raised under different temperature regimes of 10, 15 °C, 20 °C, 25 °C and 30 °C were obtained using electrospray ionization mass spectrometry (ESI-MS), and principal component analysis (PCA) was carried out to identify key metabolites. Several bin masses were detected by PCA loading scatter plots which separated the samples. In-house bin program selectively manifested the putative known metabolites depending on % total ions count and intensity of selected bins in the plant samples. Total phenolic and flavonoid content were harvested to highest levels (12.9 mg GAE/g DW and 9.3 mg QE/g DW), respectively, at 15 °C. Besides, pinoresinol (lignan), some of the vital amino acids such as serine, methionine, histidine and glutamine were found to be at higher amount in plants raised at 15 °C. Significant phenylpropanoids like cinnamic acid, caffeic acid and quercitol were detected at a higher concentration in plants raised at 15 °C as compared to other treatments. However, phosphoenolpyruvate, and oxalosuccinate (intermediates of the pentose phosphate pathway) were accumulated the most in plants raised at 30 °C and they were detected with lowest values at 10 °C. Glucose and deoxy-xylose 5 phosphate (intermediates of TCA cycle) were found in higher amounts at temperature treatments of 15 and 25 °C, respectively. We conclude that a low-temperature treatment (15 °C) results in a stress-induced accumulation of a variety of pharmacologically important secondary metabolites.

Changes in the essential oil content and terpene composition of rosemary (Rosmarinus officinalis L.) by using plant biostimulants

Plant biostimulants can stimulate the increase of growth, metabolism and the biosynthesis of metabolites in plants. This study investigated the changes of rosemary essential oil and its components composition under use of biostimulants for the possible reduction in use of chemical fertilizers. Treatments included biostimulants based on amino acids in four formulations, Aminolforte, Kadostim, Humiforte, and Fosnutren (each of them at 0.75 and 1.5 L ha-1), and application of N.P.K fertilizer as a control treatment (by applied complete fertilizer at 100 kg per hectar with proportion of 15:8:15 percentage of N:P:K in the fertilizer). Results showed that the essential oil content and its components were significantly affected by biostimulants application. The maximum content of essential oil was obtained at 1.5 L ha-1 Humiforte and both concentrations of Aminolforte. While, the highest content of α-pinene, 1,8-cineole, and camphor as major components of rosemary essential oil were obtained at 1.5 L ha-1 Fosnutren. In addition, the maximum content of linalool, z-pinocamphone, bornyl acetate, and caryophyllene oxide were observed at 1.5 L ha-1 Fosnutren.Although, the highest content of myrcene and verbenone was obtained in the treatment with N.P.K fertilizer, but the maximum contents of β-pinene, camphene, borneol, and α-terpineol were related to the both concentrations of Aminolforte.We can conclude that biostimulants based on amino acids can be an effective alternative in reducing the use of chemical fertilizer and increasing the quantity and quality of rosemary essential oil.

Proteome-Wide Identification of Lysine Succinylation in the Proteins of Tomato (Solanum lycopersicum).

Post-translational modification of proteins through lysine succinylation plays important regulatory roles in living cells. Lysine succinylation was recently identified as a novel post-translational modification in Escherichia coli, yeast, Toxoplasma gondii, HeLa cells, and mouse liver. Interestingly, only a few sites of lysine succinylation have been detected in plants to date. In this study, we identified 347 sites of lysine succinylation in 202 proteins in tomato by using high-resolution mass spectrometry. Succinylated proteins are implicated in the regulation of diverse metabolic processes, including chloroplast and mitochondrial metabolism. Bioinformatic analysis showed that succinylated proteins are evolutionarily conserved and involved in various cellular functions such as metabolism and epigenetic regulation. Moreover, succinylated proteins exhibit diverse subcellular localizations. We also defined six types of definitively conserved succinylation motifs. These results provide the first in-depth analysis of the lysine succinylome and novel insights into the role of succinylation in tomato, thereby elucidating lysine succinylation in the context of cellular physiology and metabolite biosynthesis in plants.

Identification of hydrogen peroxide responsive ESTs involved in phenylethanoid glycoside biosynthesis in Cistanche salsa cell culture

Hydrogen peroxide is an effective abiotic elicitor that can induce secondary metabolite biosynthesis in plants. We show that in cell suspension culture of a salt-tolerant medicinal plant Cistanche salsa, the production of bioactive components phenylethanoid glycosides (PeGs) was increased after an H2O2 treatment. To identify genes related to PeGs biosynthesis affected by H2O2, we constructed a suppression subtractive hybridization library of H2O2 responsive genes using a C. salsa cell line and identified 105 expressed sequence tags (ESTs) and 85 genes. EST library functional annotation and gene ontology analyses showed genes related to various stress responses, biosynthesis of secondary metabolites, and transcriptional regulation. Among them we identified two genes related to the PeGs biosynthesis pathway (4-coumarate coenzyme A ligase and cinnamate 4-hydroxylase), and two WRKY type transcription factors. The expressions of selected genes after the H2O2 treatment were analyzed by RT-qPCR. An early increased transcription of PeG biosynthesis pathway genes after the treatment revealed that H2O2 induced PeGs biosynthesis via up-regulation of its key genes.

Conversion of anthranilate synthase into isochorismate synthase: implications for the evolution of chorismate-utilizing enzymes.

Chorismate-utilizing enzymes play a vital role in the biosynthesis of metabolites in plants as well as free-living and infectious microorganisms. Among these enzymes are the homologous primary metabolic anthranilate synthase (AS) and secondary metabolic isochorismate synthase (ICS). Both catalyze mechanistically related reactions by using ammonia and water as nucleophiles, respectively. We report that the nucleophile specificity of AS can be extended from ammonia to water by just two amino acid exchanges in a channel leading to the active site. The observed ICS/AS bifunctionality demonstrates that a secondary metabolic enzyme can readily evolve from a primary metabolic enzyme without requiring an initial gene duplication event. In a general sense, these findings add to our understanding how nature has used the structurally predetermined features of enzyme superfamilies to evolve new reactions.

Jasminum polyanthum Franch. as a natural source of (−)‐methyl jasmonate: an alternative to the use of the synthetic standard

Methyl jasmonate (MJ) contains two chiral centres at C-3 and C-7 in its chemical structure, which implies that it can exist in four possible stereoisomeric forms, namely (+)-MJ, (-)-MJ, (+)-epiMJ and (-)-epiMJ. The absolute configuration of the two side chains of MJ affects the biological activity associated with this compound. To isolate pure (-)-MJ from a natural source, Jasminum polyanthum Franch., with the intention of increasing the knowledge about its biological properties, including its effect on the biosynthesis of plant metabolites. The method used was based on steam distillation extraction (SDE) as an extraction technique followed by high-performance liquid chromatography (HPLC) as a purification procedure. The HPLC flow-rate as well as the number of fractions accumulated were optimised to achieve the concentration and purity required. The employment of 0.3 mL/min as HPLC flow-rate and the accumulation of three HPLC fractions allowed the required enantiomeric purity (95%) and concentration (0.36 mg/L in each HPLC fraction) to efficiently obtain (-)-methyl jasmonate from Jasminum polyanthum Franch. to be achieved. The approach proposed may enable the properties and effect of pure (-)-MJ on plant responses to be studied. The use of a natural source to obtain (-)-MJ is presented as an alternative to the enantioselective synthesis and enantiomeric resolution from the standard racaemic mixture.

Monitoring the impact of high-pressure processing on the biosynthesis of plant metabolites using plant cell cultures

Monitoring the impact of high-pressure processing on the biosynthesis of plant metabolites using plant cell cultures