Formation Of Secondary Metabolites Research Articles

Histone H2B lysine 122 and lysine 130, as the putative targets of Penicillium oxalicum LaeA, play important roles in asexual development, expression of secondary metabolite gene clusters, and extracellular glycoside hydrolase synthesis.

Core histones in the nucleosome are subject to a wide variety of posttranslational modifications (PTMs), such as methylation, phosphorylation, ubiquitylation, and acetylation, all of which are crucial in shaping the structure of the chromatin and the expression of the target genes. A putative histone methyltransferase LaeA/Lae1, which is conserved in numerous filamentous fungi, functions as a global regulator of fungal growth, virulence, secondary metabolite formation, and the production of extracellular glycoside hydrolases (GHs). LaeA's direct histone targets, however, were not yet recognized. Previous research has shown that LaeA interacts with core histone H2B. Using S-adenosyl-L-methionine (SAM) as a methyl group donor and recombinant human histone H2B as the substrate, it was found that Penicillium oxalicum LaeA can transfer the methyl groups to the C-terminal lysine (K) 108 and K116 residues in vitro. The H2BK108 and H2BK116 sites on recombinant histone correspond to P. oxalicum H2BK122 and H2BK130, respectively. H2BK122A and H2BK130A, two mutants with histone H2B K122 or K130 mutation to alanine (A), were constructed in P. oxalicum. The mutants H2BK122A and H2BK130A demonstrated altered asexual development and decreased extracellular GH production, consistent with the findings of the laeA gene deletion strain (ΔlaeA). The transcriptome data showed that when compared to wild-type (WT) of P. oxalicum, 38 of the 47 differentially expressed (fold change ≥ 2, FDR ≤ 0.05) genes that encode extracellular GHs showed the same expression pattern in the three mutants ΔlaeA, H2BK122A, and H2BK130A. The four secondary metabolic gene clusters that considerably decreased expression in ΔlaeAalso significantly decreased in H2BK122A or H2BK130A. The chromatin of promotor regions of the key cellulolytic genes cel7A/cbh1 and cel7B/eg1 compacted in the ΔlaeA, H2BK122A, and H2BK130A mutants, according to the results of chromatin accessibility real-time PCR (CHART-PCR). The chromatin accessibility index dropped. The histone binding pocket of the LaeA-methyltransf_23 domain is compatible with particular histone H2B peptides, providing appropriate electrostatic and steric compatibility to stabilize these peptides, according to molecular docking. The findings of the study demonstrate that H2BK122 and H2BK130, which are histone targets of P. oxalicum LaeA in vitro, are crucial for fungal conidiation, the expression of gene clusters encoding secondary metabolites, and the production of extracellular GHs.

An overview of the two-component system GarR/GarS role on antibiotic production in Streptomyces coelicolor

The Streptomyces genus comprises Gram-positive bacteria known to produce over two-thirds of the antibiotics used in medical practice. The biosynthesis of these secondary metabolites is highly regulated and influenced by a range of nutrients present in the growth medium. In Streptomyces coelicolor, glucose inhibits the production of actinorhodin (ACT) and undecylprodigiosin (RED) by a process known as carbon catabolite repression (CCR). However, the mechanism mediated by this carbon source still needs to be understood. It has been observed that glucose alters the transcriptomic profile of this actinobacteria, modifying different transcriptional regulators, including some of the one- and two-component systems (TCSs). Under glucose repression, the expression of one of these TCSs SCO6162/SCO6163 was negatively affected. We aimed to study the role of this TCS on secondary metabolite formation to define its influence in this general regulatory process and likely establish its relationship with other transcriptional regulators affecting antibiotic biosynthesis in the Streptomyces genus. In this work, in silico predictions suggested that this TCS can regulate the production of the secondary metabolites ACT and RED by transcriptional regulation and protein–protein interactions of the transcriptional factors (TFs) with other TCSs. These predictions were supported by experimental procedures such as deletion and complementation of the TFs and qPCR experiments. Our results suggest that in the presence of glucose, the TCS SCO6162/SCO6163, named GarR/GarS, is an important negative regulator of the ACT and RED production in S. coelicolor.Key points• GarR/GarS is a TCS with domains for signal transduction and response regulation• GarR/GarS is an essential negative regulator of the ACT and RED production• GarR/GarS putatively interacts with and regulates activators of ACT and RED

Metabolic re-programming in confrontations of Colletotrichum graminicola and Aspergillus nidulans with Bacillus biocontrol agents

AbstractWe established confrontations between two different fungi, i.e., the maize anthracnose and stalk rot pathogen Colletotrichum graminicola, and the ubiquitous fungus Aspergillus nidulans, and different biocontrol species, i.e., Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens. In all fungus–bacterium confrontations tested, growth arrest and, thus, distance inhibition was observed on solid substrata. LC–MS/MS analyses of culture filtrates suggested formation of several metabolites only synthesized in confrontations. Interestingly, microscopy of fungal hyphae grown in liquid medium showed protrusions and color changes occurred only in media harboring fungus-bacterium confrontations. These observations indicate metabolic re-programming and suggest formation of putative secondary metabolites in interactions involving microbial biocontrol agents.

Studying the acids and amino acid composition of horse chestnut flowers

Introduction. Currently, there is an increasing trend towards assessing the full spectrum of chemical compounds in plant materials. One of the first steps in the formation of secondary metabolites of complex structure, participating in biochemical processes in the plant body, which have their own effect on the human and animal body, are organic acids (OA) and amino acids (AA). However, due attention is not always given to these compounds when studying the component composition of plant raw materials.Aim. The purpose of the work was to study the profile and quantitative assessment of the content of organic acids and amino acids of Aesculus hippocastanum L. flowers.Materials and methods. The object of the study were horse chestnut flowers, collected during flowering in the Voronezh region in 2021 and dried by air-shade method. Quantitative assessment of the amount of TC in terms of malic acid and ascorbic acid was carried out titrimetrically according to the methods presented in the State Pharmacopoeia of the Russian Federation, XIV edition. The composition of the OA and AA profiles of horse chestnut flowers was determined using the capillary electrophoresis method ("Kapel®-105/105M", Group of Companies "Lumex", Russia).Results and discussion. The method of capillary electrophoresis revealed the presence of 12 compounds of the OA group in a total amount of 4.7 % (in terms of absolutely dry raw materials). The rationality of recalculating the content of the sum of OA to the major component – citric acid, which amounted to 1.65 ± 0.04 %, was shown. The content of ascorbic acid was low (0.033 ± 0.007) %. Using the TLC method, the presence of 5 zones of compounds belonging to the AA class was established in the aqueous extract of horse chestnut flowers. The quantitative content of the sum of free AA in terms of glutamine, determined by the spectrophotometric method, was 2.25 ± 0.07 % (n = 5). The presence of 17 AA was determined by capillary electrophoresis, which amounted to 7.13 %. Glutamic acid is present in the greatest quantity in horse chestnut flowers (1.19 %). Essential amino acids amounted to 2.27 %; leucine was present in the predominant amount (0.58 %).Conclusion. A study was carried out of the qualitative composition and quantitative content of organic acids and amino acids of horse chestnut flowers. The composition of the profile and the quantitative content of organic acids and amino acids have been established. It was revealed that citric acid prevails in the total organic acids; glutamic, aspartic acid, arginine and proline are found in greater quantities in the total amino acids.

Antioxidant and in vitro cosmeceutical activities of germinated oats

AbstractBackground and ObjectivesOat (Avena sativa L.) is well known for its biofunctional properties, primarily attributed to cereal phytochemicals. Germination may amplify the formation of secondary metabolites in oat, enhancing its nutritional and bioactive quality. Despite this, the impact of germination of oat on skin health remains unknown. This study investigated how germination influences the in vitro antioxidant activity and enzyme inhibitory activity related to skin health (tyrosinase and elastase).FindingsOat was germinated at 25°C for 6 days, and the germinated samples were collected every 2 days. The samples were then divided into kernel and radicle (including germ) fractions for analysis. The radicle fraction exhibited significantly higher antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH] radical scavenging) and in vitro cosmeceutical activity compared to the whole kernel. Phenolic acids were identified to be responsible for the antioxidant activity and tyrosinase inhibition at all germination times, whereas phytosterols including β‐sitosterol played the key role in elastase inhibition. Avenanthramides, synthesized during oat germination, were proved to be crucial in inhibiting the enzymes deteriorating skin health.ConclusionsThis study revealed that germination, as a bioconversion process, enhanced antioxidant activity and cosmeceutical activity of oat by inhibiting the key enzymes responsible for skin aging. However, further research is imperative to fully comprehend the roles and mechanisms of these substances produced during germination.Significance and NoveltyThis study revealed the impacts of germination with cereals, offering valuable insights into the strategies for future investigations in the field of skin health and bioactive cereal compounds.

Bioreactor study of the metabolic repertoire and morphology of actinomycete Streptomyces rimosus ATCC 10970 under various initial concentrations of carbon and nitrogen sources

This work aims at investigating the influence of the initial concentrations of carbon (glucose) and organic nitrogen (yeast extract) sources on Streptomyces rimosus ATCC10970 secondary metabolism in the stirred tank bioreactors. Additionally, glucose utilisation, biomass formation, pH, redox potential and dissolved oxygen levels, and the morphological development of S. rimosus pseudomycelium were studied. Eighteen secondary metabolites were detected by mass spectrometry and identified with the use of the authentic standard, or putatively with the use of literature and database of secondary metabolites. Varied initial yeast extract concentration acted much stronger on the formation of secondary metabolites than glucose did. For example, oxytetracycline was not biosynthesised at high yeast extract concentration while the formation of three other metabolites was enhanced under these conditions. In the case of glucose its increasing initial concentration led to higher secondary metabolite levels with the exception of an unnamed angucycline. High initial yeast extract concentration also drastically changed S. rimosus pseudomycelial morphology from the pelleted to the dispersed one. Ultimately, the cultivation media with the varied initial levels of carbon and nitrogen sources were proved to have the marked effect on S. rimosus secondary metabolism and to be the simplest way to either induce or block the formation of the selected secondary metabolites.

Global Climate Change and Its Effects on Medicinal and Aromatic Plants: A Review Article

Medicinal herbs have been used for a long time to cure health problems and prevent disease, including epidemics. Medicinal plants are used for different purposes and in diverse uses of human beings. People around them have a basic knowledge and using through their traditional medicine from the past several years. Natural and manmade calamities, such as rapid climate change, urban growth, industrial boom, overpopulation pollution, declining forest cover, habitat loss, over-harvesting, destructive harvesting, and floods, are the principal reasons of the reduction of wild medicinal plant species. The life cycles and distribution of the world's vegetation, especially wild medicinal plants, are being affected by climate change. The impact of global climate change on medicinal plants could have a huge influence, especially in terms of their utility in conventional medication systems and as economically useful plants. The current essay emphasises the importance of study to improve our understanding of climate influences on medicinal plants properties, phenology and metabolic responses. The purpose of this paper is to review the impact of abiotic variables on secondary metabolite formation and different adaptation measures as well as future research initiatives. Furthermore, such issues with global climate change will undoubtedly become more visible or immediate threats, putting further strain on medicinal plant species. The impact of global climate change on medicinal plants could negatively correlate with environment concerns parameters, especially in terms of their utility in conventional medication systems and as economically useful plants.

Fungal-Mediated Biotransformation of the Plant Growth Regulator Forchlorfenuron by Cunninghamella elegans.

The synthetic cytokinin forchlorfenuron (FCF), while seemingly presenting relatively low toxicity for mammalian organisms, has been the subject of renewed scrutiny in the past few years due to its increasing use in fruit crops and potential for bioaccumulation. Despite many toxicological properties of FCF being known, little research has been conducted on the toxicological effects of its secondary metabolites. Given this critical gap in the existing literature, understanding the formation of relevant FCF secondary metabolites and their association with mammalian metabolism is essential. To investigate the formation of FCF metabolites in sufficient quantities for toxicological studies, a panel of four fungi were screened for their ability to catalyze the biotransformation of FCF. Of the organisms screened, Cunninghamella elegans (ATCC 9245), a filamentous fungus, was found to convert FCF to 4-hydroxyphenyl-forchlorfenuron, the major FCF secondary metabolite identified in mammals, after 26 days. Following the optimization of biotransformation conditions using a solid support system, media screening, and inoculation with a solid pre-formed fungal mass of C. elegans, this conversion time was significantly reduced to 7 days-representing a 73% reduction in total reaction time as deduced from the biotransformation products and confirmed by LC-MS, NMR spectroscopic data, as well as a comparison with synthetically prepared metabolites. Our study provides the first report of the metabolism of FCF by C. elegans. These findings suggest that C. elegans can produce FCF secondary metabolites consistent with those produced via mammalian metabolism and could be used as a more efficient, cost-effective, and ethical alternative for producing those metabolites in useful quantities for toxicological studies.

The Regulatory Effect of Nitrogen on the Formation and Accumulation of Secondary Metabolites in Different Genotypes of Camellia Sinensis (L.) Kuntze

The Regulatory Effect of Nitrogen on the Formation and Accumulation of Secondary Metabolites in Different Genotypes of Camellia Sinensis (L.) Kuntze

Evaluation of phytochemical responses and paclitaxel content of yew (Taxus baccata) seedlings subjected to the systemic fungicides

AbstractEndophytic fungi pass all or at least a part of their life cycle inside or between host cells in living plant tissues. These fungi are not capable of causing disease in the host plants, however, they are deemed to be associated with the production of some secondary metabolites in plants. Therefore, this study was laid out to shed light on how fungicides are involved in the formation of key metabolites of yew (Taxus baccata L.), especially taxol. Through the symbiotic fungal endophyte activities and population changes an experiment was conducted as a completely randomized block design using two foliar application treatments of Rovral‐TS and Fosetyl aluminium fungicides. Plants sprayed with distilled water were used as a control. The findings revealed that the diversity of endophytic fungi declined with the application of systemic fungicides, leading to a decrease in the production of certain secondary metabolites. Specifically, the levels of paclitaxel decreased by 35%, while the photosynthetic pigments chlorophyll‐a, chlorophyll‐b and total chlorophyll decreased by 26%, 20.6% and 19.6%, respectively. Additionally, the levels of carotenoids, total phenol and total flavonoids decreased by 18%, 15% and 21.8%, respectively. The highest amount of these compounds was observed in the control treatment. An increase in antioxidant activity, soluble sugars and proline content was observed soon after fungicides application. The variation in the content of soluble sugars, proline and antioxidant activity was fungicide‐dependent. Compared to Fosetyl aluminium fungicide, the numerical value of the above parameters in plants treated with Rovral‐TS was 14.4%, 11.7% and 25.4% higher, respectively. The fungicide‐mediated induction of Taxol production—key secondary metabolites in yew—was to a great extent associated with the change in endophytic fungi. This further establishes the role of fungal endophytes in the stimulation of secondary metabolite formation in yew plants.

Effect of cherry products addition on beer fermentation

Fruits has been used in brewing as a source of sugars, colour and flavour. Cherry (Prunus avium L.) products such as juice and pomace can be used in brewing in order to increase beer biological value. In this study, cherry juice and pomace in concentration of 15 % were added at first and seventh day of beer fermentation. The effect of cherry products addition was investigated by measuring the content of yeast metabolites (ethanol, aldehydes, higher alcohols, esters, and vicinal diketones) in cherry beers and control sample without cherries. The alcohol content in all the cherry beers was higher than the control sample. The cherry juice addition at the beginning of fermentation led to the formation of more secondary metabolites than the control. Cherry juice addition at the seventh day of fermentation resulted in a decrease in higher alcohols and esters concentration, but in an increase in carbonyls concentration compared to the control. Cherry pomace addition led to a significant increase in esters and vicinal diketones concentration. Aldehydes concentration was not affected by cherry pomace addition. Higher alcohols were influenced only by pomace addition at the seventh day of fermentation. Sensory evaluation was also made because yeast metabolites affected beer flavour and aroma.

Analysis of Characteristics in the Macro-Composition and Volatile Compounds of Understory Xiaobai White Tea.

Understory planting affects the growth environment of tea plants, regulating the tea plant growth and the formation of secondary metabolites, which in turn affects the flavor of Xiaobai white tea. The present research adopted biochemical composition determination, widely targeted volatilities (WTV) analysis, multivariate statistical analysis, and odor activity value (OAV) analysis to analyze the characteristics in the macro-composition and volatile compounds of understory white tea. The sensory evaluation results indicated that understory Xiaobai white tea (LWTs) was stronger than ordinary Xiaobai white tea (PWTs) in terms of the taste of smoothness, sweetness, and thickness as well as the aromas of the flower and sweet. Understory planting reduced light intensity and air temperature, increased air humidity, organic matter, total nitrogen, and available nitrogen contents, which improved the growth environment of tea plants. The phytochemical analysis showed that the water-extractable substances, caffeine, flavonoids, and soluble sugar contents of understory tea fresh-leaf (LF) were higher than those of ordinary fresh-leaf (PF). The phytochemical analysis showed that the free amino acids, theaflavins, thearubigins, water-extractable substances, and tea polyphenols contents of LWTs were significantly higher than those of PWTs, which may explain the higher smoothness, sweetness, and thickness scores of LWTs than those of PWTs. The 2-heptanol, 2-decane, damasone, and cedar alcohol contents were significantly higher in LWTs than in PWTs, which may result in stronger flowery and sweet aromas in LWTs than in PWTs. These results provide a firm experimental basis for the observed differences in the flavor of LWTs and PWTs.

Plant Tissue Culture and Formation of Secondary Metabolites - A Review

Many copies of a single plant can be grown using the plant tissue culture technology. These copies have the right characteristics to satisfy medical and nutritional demands. Secondary metabolites are purposefully synthesized by using the in vitro technique. These metabolites act as protectors for plants during stressful conditions and offer resistance against different organisms and factors, ultimately helping the plant to survive. With the passage of time, the development of new instruments for the improved synthesis of secondary metabolites via the genetic control of biosynthetic pathways has been aided by the speedy development of recombinant DNA technology. Plants generate a wide range of secondary metabolites that have various biological functions, such as fungicide, herbicide, anti-parasitic, and anti- microbial functions. Nanotechnology has the potential to drastically alter conventional plant growing methods and bring about the synthesis of flavonoids, anthocyanin, and diosgenin by using silver nanoparticles and cadmium oxide nanoparticles (CdONPs). The technique of callus cultures is increasingly utilized to produce secondary metabolites. Hence, the main objective of the current review is to increase the synthesis of secondary metabolites.

Mechanisms governing the impact of nitrogen stress on the formation of secondary metabolites in Artemisia argyi leaves

Nitrogen is a key factor in various physiological and metabolic processes in plants. Providing an adequate supply of nitrogen is essential for improving the total yield and quality of the medicinal plant Artemisia argyi (A. argyi), but the underlying mechanisms of how this nutrient alters the crop remains unclear. In this study, we conducted a series of pot experiments to investigate the agronomic traits and active components in the leaves of A. argyi plants under low and high nitrogen stress. Additionally, we used transcriptome analysis and RT-qPCR to explore the molecular pathways associated with nitrogen stress. Our results demonstrate a dramatic increase in the accumulation of phenolic acids and flavonoids in the low nitrogen (LN) stress group compared to the control (CK), with increases of 40.00% and 79.49%, respectively. Interestingly, plants in the high nitrogen (HN) stress group exhibited enhanced plant growth with larger leaves, thicker stems, and a 3% increase in volatile oil content compared to the CK. Moreover, A. argyi in the HN group displayed a 66% increase in volatile oil concentration compared to the LN group. Our combined transcriptome and q-PCR results indicate that LN stress promotes the expression of genes involved in flavonoid synthesis, while HN stress promotes the expression of genes related to terpene skeleton production and photosynthesis. Taken together, these findings suggest that different gene expression levels under LN and HN stress contribute to the photosynthesis capacity and the accumulation of active ingredients in A. argyi leaves. Our results elucidate the physiological and molecular mechanisms of nitrogen stress on A. argyi secondary metabolites and guide fertilization strategies for plant cultivation.

Advances in DNA methylation and demethylation in medicinal plants: a review.

DNA methylation and demethylation are widely acknowledged epigenetic phenomena which can cause heritable and phenotypic changes in functional genes without changing the DNA sequence. They can thus affect phenotype formation in medicinal plants. However, a comprehensive review of the literature summarizing current research trends in this field is lacking. Thus, this review aims to provide an up-to-date summary of current methods for the detection of 5-mC DNA methylation, identification and analysis of DNA methyltransferases and demethyltransferases, and regulation of DNA methylation in medicinal plants. The data showed that polyploidy and environmental changes can affect DNA methylation levels in medicinal plants. Changes in DNA methylation can thus regulate plant morphogenesis, growth and development, and formation of secondary metabolites. Future research is required to explore the mechanisms by which DNA methylation regulates the accumulation of secondary metabolites in medicinal plants.

Utilizing X-ray fluorescence (XRF) method to evaluate the content of metal elements in soil and their effects on the total phenolic and flavonoid contents of some medicinal plants.

Soil factors, especially metal elements in the soil, play a significant role in forming and accumulating secondary metabolites, which determine the medicinal properties of medicinal herbs. In this study, the concentrations of some metal elements (K, Mn, Fe, Cu, Zn, and Cr) in Cam Mountain and Tinh Bien Town, An Giang Province, Vietnam, were determined using the XRF method. We simultaneously determined the total phenolic and flavonoid content of some medicinal herbs collected from the collected soil sample areas, thereby assessing the influence of these elements on the formation of secondary metabolites in medicinal plants. The results showed that K, Mn, and Cr were mainly concentrated in the topsoil and transition layers; Fe and Cu elements tended to concentrate in the transition layer and the subsoil when surveying the soil profile. K, Mn, Cu, and Cr concentrations were more focused in Tinh Bien area, while Fe and Zn had higher concentrations at Cam Mountain. Additionally, results from evaluating the relationship between the content of the elements in the soil and the content of two active compounds also showed the correlation regression model between Zn and flavonoid expression by level 4 at the 5% significance level. Thus, the nonlinear model is suitable for evaluating the relationship between the content of metal elements in the soil and the active compound in medicinal plants.

Light in the box—photobiological examination chamber with light trap ventilation system for studying fungal surface cultures illustrated with Metarhizium brunneum and Beauveria brongniartii

Due to their versatile way of life as saprophytes, endophytes, and entomopathogens, fungi of the genera Metarhizium and Beauveria are exposed to varying illumination conditions in their natural habitats, which makes a thorough adaptation to light very likely. While the few available studies for these genera support this assumption, research in this field is still in its infancy and the data material restricted to only a few fungal species. Thus, the aim of this work was to explore how light influences growth, conidial production and secondary metabolite formation of two industrial relevant strains of M. brunneum (MA 43, formerly M. anisopliae var. anisopliae BIPESCO 5/F52) and B. brongniartii (BIPESCO 2). To achieve this, we constructed an easily adjustable illumination device for highly standardized photophysiological studies of fungi on Petri dishes, the so-called LIGHT BOX. With the aid of this device, M. brunneum and B. brongniartii were grown on S4G or S2G agar at 25 °C for 14 days either in complete darkness or under constant illumination with red light (λpeak = 635 nm), green light (λpeak = 519 nm) or blue light (λpeak = 452 nm). In addition, for each wavelength the effect of different illumination intensities was tested, i.e., intensities of red light ranging from 22.1 ± 0.1 to 136.5 ± 0.3 µW cm-2, green light from 16.5 ± 0.1 to 96.2 ± 0.1 µW cm-2, and blue light from 56.1 ± 0.2 to 188.9 ± 0.6 µW cm-2. Both fungi strongly responded in terms of growth, conidial production, pigmentation and morphology to changes in the wavelength and irradiation intensity. The wavelength-dependent production of the well-known secondary metabolite oosporein which is secreted by the genus Beauveria in particular, was also increased under green and blue light exposure. The established LIGHT BOX system allows not only to optimize conidial production yields with these biotechnologically relevant fungi, but also allows the photobiological exploration of other fungi.

Insights into the genome of Methylobacterium sp. NMS14P, a novel bacterium for growth promotion of maize, chili, and sugarcane.

A novel methylotrophic bacterium designated as NMS14P was isolated from the root of an organic coffee plant (Coffea arabica) in Thailand. The 16S rRNA sequence analysis revealed that this new isolate belongs to the genus Methylobacterium, and its novelty was clarified by genomic and comparative genomic analyses, in which NMS14P exhibited low levels of relatedness with other Methylobacterium-type strains. NMS14P genome consists of a 6,268,579 bp chromosome, accompanied by a 542,519 bp megaplasmid and a 66,590 bp plasmid, namely pNMS14P1 and pNMS14P2, respectively. Several genes conferring plant growth promotion are aggregated on both chromosome and plasmids, including phosphate solubilization, indole-3-acetic acid (IAA) biosynthesis, cytokinins (CKs) production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, sulfur-oxidizing activity, trehalose synthesis, and urea metabolism. Furthermore, pangenome analysis showed that NMS14P possessed the highest number of strain-specific genes accounting for 1408 genes, particularly those that are essential for colonization and survival in a wide array of host environments, such as ABC transporter, chemotaxis, quorum sensing, biofilm formation, and biosynthesis of secondary metabolites. In vivo tests have supported that NMS14P significantly promoted the growth and development of maize, chili, and sugarcane. Collectively, NMS14P is proposed as a novel plant growth-promoting Methylobacterium that could potentially be applied to a broad range of host plants as Methylobacterium-based biofertilizers to reduce and ultimately substitute the use of synthetic agrochemicals for sustainable agriculture.

Spatial dynamic simulation of important cash crops based on phenology with Scutellaria baicalensis Georgi as an example

Substantial differences in the niche and quality of plants, especially in cash crops, are clearly observed in different phenological phases. Many plants have distinct phenological characteristics, yet the distribution patterns and secondary metabolites in plants at different growth stages are poorly understood. We examined the importance of environmental variables in phenological phases for plant niches and quality using 30 years of species spatial occurrence point data combined with phenological data and other environmental factors. First, we developed niche models for Scutellaria baicalensis Georgi to estimate the distributions of habitat suitability and spatial dynamics for five developmental stages. Our results suggested that some populations were lost when environmental factors in specific phenological stages were involved in modeling and that these environmental variables contributed more than 30 % of the total to species distribution modeling. The results of independent phenological niche modeling illustrated the spatial variation dynamics of S. baicalensis, and 22.88 % of the potential distribution areas were consistent among the five phenological periods. Additionally, we considered the impact of environmental variables in five growth stages on quality. Six environmental variables (maximum temperature during the flowering period, maximum temperature during the blooming period, maximum temperature during the fruiting period, phenological precipitation during the fruiting period, precipitation standard deviation during the fruiting period, and phenological precipitation during the withering period) played pivotal roles in the formation of secondary metabolites and affected the spatial distribution of plant quality. Our study demonstrates the importance of phenological phases and highlights that they should be considered if plants have distinct phenological signatures. In regard to cultivation and management, our results provide decision-makers with an integrative approach for planning the rational allocation of resources used to obtain medicinal plants.

The fate of secondary metabolites in plants growing on Cd-, As-, and Pb-contaminated soils-a comprehensive review.

The study used scattered literature to summarize the effects of excess Cd, As, and Pb from contaminated soils on plant secondary metabolites/bioactive compounds (non-nutrient organic substances). Hence, we provided a systematic overview involving the sources and forms of Cd, As, and Pb in soils, plant uptake, mechanisms governing the interaction of these risk elements during the formation of secondary metabolites, and subsequent effects. The biogeochemical characteristics of soils are directly responsible for the mobility and bioavailability of risk elements, which include pH, redox potential, dissolved organic carbon, clay content, Fe/Mn/Al oxides, and microbial transformations. The radial risk element flow in plant systems is restricted by the apoplastic barrier (e.g., Casparian strip) and chelation (phytochelatins and vacuole sequestration) in roots. However, bioaccumulation is primarily a function of risk element concentration and plant genotype. The translocation of risk elements to the shoot via the xylem and phloem is well-mediated by transporter proteins. Besides the dysfunction of growth, photosynthesis, and respiration, excess Cd, As, and Pb in plants trigger the production of secondary metabolites with antioxidant properties to counteract the toxic effects. Eventually, this affects the quantity and quality of secondary metabolites (including phenolics, flavonoids, and terpenes) and adversely influences their antioxidant, antiinflammatory, antidiabetic, anticoagulant, and lipid-lowering properties. The mechanisms governing the translocation of Cd, As, and Pb are vital for regulating risk element accumulation in plants and subsequent effects on secondary metabolites.