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Chlorophyll c is a key photosynthetic pigment that has been used historically to classify eukaryotic algae. Despite its importance in global photosynthetic productivity, the pathway for its biosynthesis has remained elusive. Here we define the CHLOROPHYLL C SYNTHASE (CHLCS) discovered through investigation of a dinoflagellate mutant deficient in chlorophyll c. CHLCSs are proteins with chlorophyll a/b binding and 2-oxoglutarate-Fe(II) dioxygenase (2OGD) domains found in peridinin-containing dinoflagellates; other chlorophyll c-containing algae utilize enzymes with only the 2OGD domain or an unknown synthase to produce chlorophyll c. 2OGD-containing synthases across dinoflagellate, diatom, cryptophyte, and haptophyte lineages form a monophyletic group, 8 members of which were also shown to produce chlorophyll c. Chlorophyll c1 to c2 ratios in marine algae are dictated in part by chlorophyll c synthases. CHLCS heterologously expressed in planta results in the accumulation of chlorophyll c1 and c2, demonstrating a path to augment plant pigment composition with algal counterparts.

Enzymatic biocatalysis typically generates less waste, uses less water, and minimizes energy consumption compared to traditional chemical methods. Efficient, cell-free biosynthesis relies on the reuse of its valuable biocatalysts. Immobilization of enzymes on solid supports, such as enzyme carrier resins (ECRs), offers a reliable and widely deployed approach to maximize enzyme turnover in cell-free biosynthesis. We focus on two major bottlenecks associated with optimizing cell-free biocatalysis. First, we apply our lab's 3D-printed labware to screen ECRs in 96-well mini-reactors to optimize enzyme immobilization conditions. Second, we introduce inline infrared spectroscopy to monitor bioreactor output and maximize enzyme productivity. Urease provides a model system for examining immobilization conditions and continuous assessment of biocatalyst performance. As required for the high substrate concentrations to improve process efficiency and minimize waste, urease was studied in unusually high concentrations of its substrate – molar concentrations of urea. The optimized reactor processed 3.24 L of 4.00 M urea at an average volumetric productivity of 13 g ⋅ L−1 ⋅ h−1 over 18 h and achieved an estimated productivity number of >17.4 kg urea processed per g of immobilized urease Type-IX. This workflow can be generalized to most biocatalytic processes and could accelerate adoption of cell-free biosynthesis for greater chemical sustainability.

The assembly line biosynthesis of the powerful anticancer-antiviral didemnin cyclic peptides is proposed to follow a prodrug release mechanism in Tristella bacteria. This strategy commences with the formation of N-terminal prodrug scaffolds and culminates in their cleavage during the cellular export of the mature products. In this study, a comprehensive exploration of the genetic and biochemical aspects of the enzymes responsible for both the assembly and cleavage of the acylated peptide prodrug scaffolds is provided. This process involves the assembly of N-acyl-polyglutamine moieties orchestrated by the nonribosomal peptide synthetase DidA and the cleavage of these components at the post-assembly stage by DidK, a transmembrane CAAX hydrolase homolog. The findings not only shed light on the complex prodrug mechanism that underlies the synthesis and secretion of didemnin compounds but also offer novel insights into the expanded role of CAAX hydrolases in microbes. Furthermore, this knowledge can be leveraged for the strategic design of genome mining approaches aimed at discovering new bioactive natural products that employ similar prodrug biochemical strategies.

This study highlights the significance of overexpressing 1-deoxy-d-xylulose-5-phosphate synthase (DXS) from the MEP (methylerythritol 4-phosphate) pathway, in addition to short-chain prenyltransferase fusions for the improved production of the diterpene, taxa-4,11-diene, the first committed intermediate in the production of anti-cancer drug paclitaxel. The results showed that the strain which has (i) the taxadiene synthase (txs) gene integrated into the genome, (ii) the MEP pathway genes overexpressed, (iii) the fpps-crtE prenyltransferases fusion protein and (iv) additional expression of 1-deoxy-d-xylulose-5-phosphate synthase (DXS), yielded the highest production of taxa-4,11-diene at 390 mg/L (26 mg/L/OD 600). This represents a thirteen-fold increase compared to the highest reported concentration in B. subtilis. The focus on additional overexpression of DXS and utilizing short-chain prenyltransferase fusions underscores their pivotal role in achieving significant titer improvements in terpene biosynthesis. [Display omitted] • Utilizing Bacillus subtilis as a cell factory for the production of taxadiene. • Additional expression of DXS from MEP pathway can boost taxadiene production. • Application of fused prenyltransferases can enhance the yield of taxadiene. • The highest taxadiene production so far in B. subtilis has been achieved. [ABSTRACT FROM AUTHOR]

Biodegradable energy storage devices are being developed for real-time monitoring of biometric data, medical diagnosis, prognosis, and therapeutic uses due to the rising need for energy storage devices in biomedical and information technologies. In this review, we have briefly discussed the environment-friendly and biodegradable electrode materials in supercapacitors, batteries, supercapattery, and skin-patchable devices. The charge storage mechanism, biocompatibility, and safety of electrode material are discussed in detail. The electrode material based on carbon, metal, and organic patchable composites is studied. Furthermore, the most essential and core part of this review is discussing the several synthesis methodologies of biological environments and how these biodegradable materials fit into the architecture of energy storage devices. Lastly, this review paper gives a deep understanding of (biodegradable and environment-friendly electrode materials) in the current energy storage systems, challenges, and research directions. [ABSTRACT FROM AUTHOR]

Transcription factors (TFs) provide potentially powerful tools for plant metabolic engineering as they often control multiple genes in a metabolic pathway. However, selecting the best TF for a particular pathway has been challenging, and the selection often relies significantly on phylogenetic relationships. Here, we offer examples where evolutionary relationships have facilitated the selection of the suitable TFs, alongside situations where such relationships are misleading from the perspective of metabolic engineering. We argue that the evolutionary trajectory of a particular TF might be a better indicator than protein sequence homology alone in helping decide the best targets for plant metabolic engineering efforts. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

Carotenoids are essential components of the photosynthetic apparatus and precursors of plant hormones, such as strigolactones (SLs). SLs are involved in various aspects of plant development and stress-response processes, including the establishment of root and shoot architecture. SL biosynthesis begins with the reversible isomerization of all-trans-carotene into 9-cis-β-carotene, catalysed by DWARF27 β-carotene isomerase (D27). Sequence comparisons have revealed the presence of D27-related proteins in photosynthetic eukaryotes and cyanobacteria lacking SLs. To gain insight into the evolution of SL biosynthesis, we characterized the activity of a cyanobacterial D27 protein (CaD27) from Cyanobacterim aponinum, using carotenoid-accumulating Escherichia coli cells and in vitro enzymatic assays. Our results demonstrate that CaD27 is an all-trans/cis and cis/cis-β-carotene isomerase, with a cis/cis conversion preference. CaD27 catalysed 13-cis/15-cis-, all-trans/9-cis-β-carotene, and neurosporene isomerization. Compared with plant enzymes, it exhibited a lower 9-cis-/all-trans-β-carotene conversion ratio. A comprehensive genome survey revealed the presence of D27 as a single-copy gene in the genomes of 20 out of 200 cyanobacteria species analysed. Phylogenetic and enzymatic analysis of CaD27 indicated that cyanobacterial D27 genes form a single orthologous group, which is considered an ancestral type of those found in photosynthetic eukaryotes. This article is part of the theme issue 'The evolution of plant meta‌bolism'. [ABSTRACT FROM AUTHOR]

Sesquiterpene lactones (STLs) are a prominent group of plant secondary metabolites predominantly found in the Asteraceae family and have multiple ecological roles and medicinal applications. This review describes the evolutionary and ecological significance of STLs, highlighting their roles in plant defence mechanisms against herbivory and as phytotoxins, alongside their function as environmental signalling molecules. We also cover the substantial role of STLs in medicine and their mode of action in health and disease. We discuss the biosynthetic pathways and the various modifications that make STLs one of the most diverse groups of metabolites. Finally, we discuss methods for identifying and predicting STL biosynthesis pathways. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

Human milk oligosaccharides (HMOs) have attracted considerable attention owing to their unique physiological functions. Two important tetrasaccharides, lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT), are core structures of HMOs. Their safety has been evaluated and they can be added to infant formula as functional ingredients. The fucosylated derivatives of LNT and LNnT, mainly lacto-N-fucopentaose (LNFP) I, LNFP II, LNFP III, and lacto-N-difucohexaose I, exhibit prominent physiological characteristics, including modificating the intestinal microbiota, immunomodulation, anti-bacterial activities, and antiviral infection. However, they have received lesser attention than 2'-fucosyllactose. As precursors, LNT and LNnT are connected to one or two fucosyl units through α1,2/3/4 glycosidic bonds, forming a series of compounds with complex structures. These complex fucosylated oligosaccharides can be biologically synthesized using enzymatic and cell factory approaches. This review summarizes the occurrence, physiological effects, and biosynthesis of fucosylated LNT and LNnT derivatives and their future development. [ABSTRACT FROM AUTHOR]

Oligosaccharides, a low polymerization degree of carbohydrate, possess various physiological activities, such as anti-diabetes, anti-obesity, anti-aging, anti-viral, and gut microbiota regulation, having a widely used in food and medical fields. However, due to the limited natural oligosaccharides, many un-natural oligosaccharides from complex polysaccharides are being studied for amplifying the available pool of oligosaccharides. More recently, various oligosaccharides were developed by using several artificial strategies, such as chemical degradation, enzyme catalysis, and biosynthesis, then they can be applied in various sectors. Moreover, it has gradually become a trend to use biosynthesis to realize the synthesis of oligosaccharides with clear structure. Emerging research has found that un-natural oligosaccharides exert more comprehensive effects against various human diseases through multiple mechanisms. However, these oligosaccharides from various routes have not been critical reviewed and summarized. Therefore, the purpose of this review is to present the various routes of oligosaccharides preparations and healthy effects, with a focus on diabetes, obesity, aging, virus, and gut microbiota. Additionally, the application of multi-omics for these natural and un-natural oligosaccharides has also been discussed. Especially, the multi-omics are needed to apply in various disease models to find out various biomarkers to respond to the dynamic change process of oligosaccharides. [ABSTRACT FROM AUTHOR]

Oxalic acid is one of the important acids that is used in many fields. It is of medical, industrial and agricultural importance and is used as an acid in foods, building and construction, pharmacy, and others. This acid is produced in multiple ways, and the biogenic method is the best method because it is safe and cheap. Hence, this study came about, where reliance was placed on wheat bran in preparing nutrient medium to produce oxalic acid from Candida albicans and Aspergillus niger yeast isolated from environmental and pathogenic sources. The study aimed to use wheat bran as an alternative medium for growing fungi and yeasts that produce oxalic acid, and to compare the productivity of this medium with standard media. One hundred fungal isolates were isolated from different environmental and clinical sources, and grown in Sabouraud dextrose agar medium (SDA) and potato dextrose agar to obtain pure isolates of A. niger and C. albicans. Thirty seven isolates of C. albicans and thirty two isolates of A. niger were isolated. Thirty one contaminated samples were discarded. The isolates were grown in standard (SDB, PDB) and alternative (wheat bran) media. The amount of acid was estimated by mulching against potassium permanganate. The results showed that wheat bran medium was the most efficient in producing oxalic acid with a rate of 26.2% for A. niger and 25.3% for C. albicans, compared to standard media. The best temperature for acid production was 32 °C with a production rate of 19.1% for A. niger and 22.7% for C. albicans. The best pH was 6.5 for A. niger with a production rate of 20.2% and 5.5 for C. albicans with a production rate of 23.3%. The study conclude from the above that the fungus A. niger is the best compared to C. albicans, as well as the medium of wheat bran is a promising and effective medium in the production of oxalic acid in an environmentally friendly way. [ABSTRACT FROM AUTHOR]

Biogenic synthesis of iron and zinc nanoparticles from carob seed extract (Ceratonia siliqua L.) and their antibacterial activity were studied. The characteristics of the prepared nanoparticles were evaluated shapes and sizes by field emission scanning electron microscopy (FESEM) analysis with mapping technique and energy dispersive X-ray analysis (EDX), and Fourier-transform infrared spectroscopy (FTIR) confirmed the functional group that contributes to the biogenic and antibacterial activity. The appearance of metal-oxygen bonds for both ZnO NPs and Fe2 O3 NPs in spectra and the presence of zinc, iron, and oxygen in varying proportions confirm the success of the biosynthesis of the nanoparticles. Ceratonia siliqua L. extract, iron, and zinc showed high effectiveness in removing bacteria from polluted water. [ABSTRACT FROM AUTHOR]

• Lasso peptides are diverse macrolactam-containing ribosomal peptide natural products distinguished by a kinetically trapped [1]rotaxane fold. • While leader peptidolysis is reasonably well understood, comparatively little is known about how lasso cyclases tie their substrates into the characteristic lariat knot. • Genome mining has enabled the accurate prediction of thousands of lasso peptides. Coupled with new expression methods, it has dramatically expanded our understanding of their diversification potential. • While some lasso peptides have established biological activities, most have elusive functions. Collaboration between natural product chemists, specialists in omics, and microbiologists will be essential to diversify bioactivity screens and understand the role of lasso peptides in the environment. Lasso peptides are a large and sequence-diverse class of ribosomally synthesized and post-translationally modified peptide (RiPP) natural products characterized by their slip knot-like shape. These unique, highly stable peptides are produced by bacteria for various purposes. Their stability and sequence diversity make them a potentially useful scaffold for biomedically relevant folded peptides. However, many questions remain about lasso peptide biosynthesis, ecological function, and diversification potential for biomedical and agricultural applications. This review discusses new insights and open questions about lasso peptide biosynthesis and biological function. The role that genome mining has played in the development of new methodologies for discovering and diversifying lasso peptides is also discussed. [ABSTRACT FROM AUTHOR]

A new series of 1,2,3-triazole skeleton incorporated pyrrole derivatives (11a–j) were developed and their chemical structures were confirmed by analytical data. Further, the anticancer profile of these newly derived compounds 11a–j was assessed against four types of human cancer cell lines such as human breast cancer (MCF-7), lung cancer (A549), colon cancer (Colo-205) and ovarian cancer (A2780) by employing of the MTT method and was compared with etoposide used as a positive control. Most of the examined derivatives displayed moderate to good activity compared with the positive control. Among them, five compounds 11a, 11b, 11c, 11d, and 11e showed more potent activity. Particularly, compound 11a showed superior activity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Utilizing fungicides to protect crops from diseases is an effective method, and novel eco‐friendly plant‐derived fungicides with high efficiency and low toxicity are urgent requirements for sustainable crop protection. RESULT: Two series of rosin‐based fungicides (totally 35) were designed and synthesized. In vitro fungicidal activity revealed that Compound 6a (Co. 6a) effectively inhibited the growth of Valsa mali [median effective concentration (EC50) = 0.627 μg mL−1], and in vivo fungicidal activity suggested a significant protective efficacy of Co. 6a in protecting both apple branches (35.12% to 75.20%) and apples (75.86% to 90.82%). Quantum chemical calculations (via density functional theory) results indicated that the primary active site of Co. 6a lies in its amide structure. Mycelial morphology and physiology were investigated to elucidate the mode‐of‐action of Co. 6a, and suggested that Co. 6a produced significant cell membrane damage, accelerated electrolyte leakage, decreased succinate dehydrogenase (SDH) protein activity, and impaired physiological and biochemical functions, culminating in mycelial mortality. Molecular docking analysis revealed a robust binding energy (ΔE = −7.29 kcal mol−1) between Co. 6a and SDH. Subsequently, biosafety evaluations confirmed the environmentally‐friendly nature of Co. 6a via the zebrafish model, yet toxicological results indicated that Co. 6a at median lethal concentration [LC50(96)] damaged the gills, liver and intestines of zebrafish. CONCLUSION: The above research offers a theoretical foundation for exploiting eco‐friendly rosin‐based fungicidal candidates in sustainable crop protection. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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Indole, a versatile outstanding heterocyclic compound, engaged in numerous pharmacological properties due to their multiple biochemical processes. The remarkable indole moiety resembles with numerous protein structures. The fascinating molecular framework of indole makes its suitable for drug development. Indole derivatives mimic the peptides structure and bind reversibly to several enzymes, which contribute enormous opportunities to develop novel drugs with distinct mechanism of action Indole, a versatile outstanding heterocyclic compound, engaged in numerous pharmacological properties due to their multiple biochemical processes. The remarkable indole moiety resembles with numerous protein structures. The fascinating molecular framework of indole makes its suitable for drug development. Indole derivatives mimic the peptides structure and bind reversibly to several enzymes, which contribute enormous opportunities to develop novel drugs with distinct mechanism of actionIndole, a versatile outstanding heterocyclic compound, engaged in numerous pharmacological properties due to their multiple biochemical processes. The remarkable indole moiety resembles with numerous protein structures. The fascinating molecular framework of indole makes its suitable for drug development. Indole derivatives mimic the peptides structure and bind reversibly to several enzymes, which contribute enormous opportunities to develop novel drugs with distinct mechanism of actionIndole, a versatile outstanding heterocyclic compound, engaged in numerous pharmacological properties due to their multiple biochemical processes. The remarkable indole moiety resembles with numerous protein structures. The fascinating molecular framework of indole makes its suitable for drug development. Indole derivatives mimic the peptides structure and bind reversibly to several enzymes, which contribute enormous opportunities to develop novel drugs with distinct mechanism of action In the present work, synthesis and biological activity of new indole based derivatives as potent anti-inflammatory agent. The derivatives were schemed and substituted, they were checked for docking scores against the Cyclooxygenase II enzyme. From that 10 best docked compounds are selected and synthesized spectral data of the synthesized compounds was obtained from IR, 1HNMR, 13CNMR, and mass spectroscopy, among the tested compounds. From the docking results, compound A7 and A10 (9.2 Kcal/mol) shows the highest binding affinity against Cyclooxygenase II enzyme possesses anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

The document is the contents list of the New Journal of Chemistry, published on October 28, 2024. It includes a list of communications and papers featured in the journal, covering various topics in chemistry such as catalytic synthesis, hydroesterification, nanoparticles, luminescence, and drug delivery. The journal is published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. [Extracted from the article]

The dengue virus (DENV) is a mosquito-borne flavivirus transmitted through the infected mosquito, primarily of the Aedes genus. Over recent decades, the significant emergence of DENV infections has posed growing challenges for control efforts. Extensive research indicates that the dengue NS2B–NS3 protease, a non-structural viral protein, is the most promising target in dengue drug research. Therefore, our study synthesized two series of novel allosteric inhibitors of the NS2B–NS3 protease to explore previous allosteric inhibitors of the protease. Meanwhile, enzyme inhibitory activities of all compounds are measured and IC50 values of the optimized compounds are obtained by utilizing a fluorescence-based assay. Notably, compound A24 demonstrates the highest enzyme inhibitory activity with an IC50 value of 16 μM. Further enzyme kinetic experiments confirm that the optimized compound A24 functions as a non-competitive inhibitor of the NS2B–NS3 protease. Through molecular docking studies, compound A24 showed a binding energy of −5.6 kcal mol−1, comparable to the lead compounds, which preliminarily explains its similar inhibitory activity. In addition, compound A24 forms a stable complex with the protein primarily through hydrogen bonds and π–π interaction, with subsequent dynamics simulations confirming the stable binding mode. In conclusion, we designed and synthesized 59 novel scaffold compounds and identified compound A24 with the highest activity through pharmacological experiments and computer-aided drug design, which targets the allosteric sites and contributes significantly to the prevention of the dengue virus. [ABSTRACT FROM AUTHOR]

Over the past 10 years, nanotechnology has emerged as a very promising technique for a wide range of biomedical applications. Green synthesized metal and metal oxide nanoparticles (NPs) are cheap, easy to produce in large quantities, and safe for the environment. Currently, efforts are being made to dope ZnO in order to improve its optical, electrical, and ferromagnetic qualities as well as its crystallographic quality. Actually, doping is one of the simplest methods for enhancing an NP's physicochemical characteristics because it involves introducing impure ions into the crystal lattice of the particle. In this study, the biosynthesis of zinc oxide NPs (ZnONPs) and metal‐doped (Mg2+ and Ag+) ZnONPs was carried out by using aqueous and water‐alcoholic extracts of Cynara scolymus L. leaves, Carthamus tinctorius L. flowers, and Rheum ribes L. (RrL) plant, which are rich in phytochemical content. Plant extracts act as a natural reducing, capping, and stabilizing agent in the production. The produced NPs were characterized using a variety of methods, such as ultraviolet‐visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM). The produced metal‐doped and undoped ZnONPs exhibited characteristic absorption peaks between 365 and 383 nm due to their surface plasmon resonance bands. SEM analysis revealed that the NPs were oval, nearly spherical, and spherical. In the FTIR spectra, the Zn–O bonding peak ranges from 400 to 700 cm−1. The peaks obtained in the range of 407–562 cm−1 clearly represent the Zn–O bond. In addition, the FTIR results showed that there were notable amounts of phenol and flavonoid compounds in both the prepared extract and ZnONPs. According to DLS analysis results, the size distribution of produced NPs is between 120 and 786 nm. The antibacterial properties of green produced NPs on Gram‐positive (Staphylococcus aureus RN4220) and Gram‐negative (Escherichia coli DH10B) bacterial strains were investigated by agar well diffusion method. In studies investigating the anticancer activities of biosynthesized NPs, mouse fibroblast cells (L929) were used as healthy cells and human cervical cancer cells (HeLa) were used as cancer cells. Only the produced Ag‐ZnONPs showed potent dose‐dependent antibacterial activity (at concentrations higher than 100 µg/mL) against Gram‐positive and Gram‐negative bacteria. RrL‐ZnONP‐600 and RrL‐ZnONP‐800 NPs produced with water–ethanol extract of RrL plant and calcined at 600 and 800°C were effective at high concentrations in healthy cells and at low concentrations in HeLa cancer cells, showing that they have the potential to be anticancer agents. The study's findings highlight the potential of green synthesis techniques in the production of medicinal nanomaterials for the treatment of cancer and other biological uses. [ABSTRACT FROM AUTHOR]

Summary In plants, L‐serine (Ser) biosynthesis occurs through various pathways and is highly dependent on the atmospheric CO2 concentration, especially in C3 species, due to the association of the Glycolate Pathway of Ser Biosynthesis (GPSB) with photorespiration. Characterization of a second plant Ser pathway, the Phosphorylated Pathway of Ser Biosynthesis (PPSB), revealed that it is at the crossroads of carbon, nitrogen, and sulphur metabolism. The PPSB comprises three sequential reactions catalysed by 3‐phosphoglycerate dehydrogenase (PGDH), 3‐phosphoSer aminotransferase (PSAT) and 3‐phosphoSer phosphatase (PSP). PPSB was overexpressed in plants exhibiting two different modes of photosynthesis: Arabidopsis (C3 metabolism), and maize (C4 metabolism), under ambient (aCO2) and elevated (eCO2) CO2 growth conditions. Overexpression in Arabidopsis of the PGDH1 gene alone or PGDH1, PSAT1 and PSP1 in combination increased the Ser levels but also the essential amino acids threonine (aCO2), isoleucine, leucine, lysine, phenylalanine, threonine and methionine (eCO2) compared to the wild‐type. These increases translated into higher protein levels. Likewise, starch levels were also increased in the PPSB‐overexpressing lines. In maize, PPSB‐deficient lines were obtained by targeting PSP1 using Cas9 endonuclease. We concluded that the expression of PPSB in maize male gametophyte is required for viable pollen development. Maize lines overexpressing the AtPGDH1 gene only displayed higher protein levels but not starch at both aCO2 and eCO2 conditions, this translated into a significant rise in the nitrogen/carbon ratio. These results suggest that metabolic engineering of PPSB in crops could enhance nitrogen content, particularly under upcoming eCO2 conditions where the activity of GPSB is limited. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSIONS Ligusticum chuanxiong Hort., with over 2000 years of medicinal use and cultivation history, is extensively used in clinical settings for treating heart disease, headache, dysmenorrhea, and amenorrhea. Constructing the geographic distribution pattern of L. chuanxiong and identifying the environmental factors limiting its range, as well as clarifying the effects of key environmental factors on the content of major active constituents and transcription regulation, could provide a scientific foundation for the conservation and effective management of this valuable medicinal resource.The results reveal that the predominant environmental factors influencing the distribution were the minimum temperature of the coldest month (Bio6) and solar radiation (Srad), with cumulative account for 87.46% of the importance. Correlation analysis further reveals significant negative correlations between Bio6 and the content of major active constituents in L. chuanxiong, with Srad exhibiting a negative correlation with these constituents. The gene differential expression analysis indicated that the expression levels of some genes associated with growth and active constituent biosynthesis pathways, such as RPT2_13888, UVR8_16871, CLPB3_3155, and 4CLL5_116, varied significantly among locations influenced by differing key environmental factors. Consequently, alterations in the environment were found to influence the gene expression levels within these pathways, resulting in variations in the content of active constituents.These findings contribute to an enhanced understanding of how environmental factors impact the distribution and quality of medicinal plants and offer a theoretical reference for the introduction, cultivation, quality improvement, resource utilization and management of L. chuanxiong. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The green method provides stable, rapid, and eco-friendly methods for synthesis nanoparticles with plant extract as capping and reducing agents. This method renders biocompatibility, scalability, and potential medical applications of nanoparticles. This study green synthesized CuO/TiO 2 and ZnO/TiO 2 nanocomposites using Parkia timoriana bark extract. The synthesized nanocomposites were determined utilizing UV–vis DRS FTIR, XRD, TGA, AFM, FE-SEM, E -DAX, HR-TEM, and XPS. Antioxidant assay and antidiabetic studies revealed the biological activity of nanocomposites. The antioxidant property in ZnO/TiO 2 (84.07 %) was higher than in CuO/TiO 2 nanocomposites (72.76 %). The IC 50 value of CuO/TiO 2 and ZnO/TiO 2 in α-amylase inhibition assay was 72.12 μg/mL and 75.95 μg/mL, respectively and IC 50 value of CuO/TiO 2 and ZnO/TiO 2 in α-glucosidase inhibition assay was 30.80 μg/ml and 25.69 μg/ml. Thus, it concludes ZnO/TiO 2 nanocomposites exhibited higher antioxidant and antidiabetic activity than CuO/TiO 2 nanocomposites. These results show that biosynthesized nanocomposites can be used for treating diseases. [ABSTRACT FROM AUTHOR]

GDP-fucose is synthesised via two pathways: de novo and salvage. The first uses GDP-mannose as a substrate, and the second uses free fucose. To date, these pathways have been considered to work separately and not to have an influence on each other. We report the mutual response of the de novo and salvage pathways to the lack of enzymes from a particular route of GDP-fucose synthesis. We detected different efficiencies of GDP-fucose and fucosylated structure synthesis after a single inactivation of enzymes of the de novo pathway. Our study demonstrated the unequal influence of the salvage enzymes on the production of GDP-fucose by enzymes of the de novo biosynthesis pathway. Simultaneously, we detected an elevated level of one of the enzymes of the de novo pathway in the cell line lacking the enzyme of the salvage biosynthesis pathway. Additionally, we identified dissimilarities in fucose uptake between cells lacking TSTA3 and GMDS proteins. [ABSTRACT FROM AUTHOR]

Background: Geranyllinalool, a natural diterpenoid found in plants, has a floral and woody aroma, making it valuable in flavors and fragrances. Currently, its synthesis primarily depends on chemical methods, which are environmentally harmful and economically unsustainable. Microbial synthesis through metabolic engineering has shown potential for producing geranyllinalool. However, achieving efficient synthesis remains challenging owing to the limited availability of terpenoid precursors in microorganisms. Thus, an artificial isopentenol utilization pathway (IUP) was constructed and introduced in Escherichia coli to enhance precursor availability and further improve terpenoid synthesis. Results: We first constructed an artificial IUP in E. coli to enhance the supply of precursor geranylgeranyl diphosphate (GGPP) and then screened geranyllinalool synthases from plants to achieve efficient synthesis of geranyllinalool (274.78 ± 2.48 mg/L). To further improve geranyllinalool synthesis, we optimized various cultivation factors, including carbon source, IPTG concentration, and prenol addition and obtained 447.51 ± 6.92 mg/L of geranyllinalool after 72 h of shaken flask fermentation. Moreover, a scaled-up production in a 5-L fermenter was investigated to give 2.06 g/L of geranyllinalool through fed-batch fermentation. To the best of our knowledge, this is the highest reported titer so far. Conclusions: Efficient synthesis of geranyllinalool in E. coli can be achieved through a two-step pathway and optimization of culture conditions. The findings of this study provide valuable insights into the production of other terpenoids in E. coli. [ABSTRACT FROM AUTHOR]

Inducible expression systems are pivotal for governing gene expression in strain engineering and synthetic biotechnological applications. Therefore, a critical need persists for the development of versatile and efficient inducible expression mechanisms. In this study, the xylose-responsive promoter xylA5p and its transcriptional regulator XylR were identified in Parageobacillus thermoglucosidasius DSM 2542. By combining promoter xylA5p with its regulator XylR, fine-tuning the expression strength of XylR, and reducing the glucose catabolite repression on xylose uptake, we successfully devised a xylose-inducible and glucose-insensitive expression system, denoted as IExyl*. This system exhibited diverse promoter strengths upon induction with xylose at varying concentrations and remained unhindered in the presence of glucose. Moreover, we showed the applicability of IExyl* in P. thermoglucosidasius by redirecting metabolic flux towards riboflavin biosynthesis, culminating in a 2.8-fold increase in riboflavin production compared to that of the starting strain. This glucose-insensitive and xylose-responsive expression system provides valuable tools for designing optimized biosynthetic pathways for high-value products and facilitates future synthetic biology investigations in Parageobacillus. Key points: • A xylose-inducible and glucose-insensitive expression system IExyl* was developed. • IExyl* was applied to enhance the riboflavin production in P. thermoglucosidasius • A tool for metabolic engineering and synthetic biology research in Parageobacillus strains. [ABSTRACT FROM AUTHOR]

Of the hitherto over 60 taxonomically identified species in the genus of Pseudo-nitzschia, 26 have been confirmed to be toxigenic. Nevertheless, the acquisition and evolution of the toxin biosynthesis (dab) genes by this extensive group of Pseudo-nitzschia species remains unclear. Through constructing chromosome-level genomes of three Pseudo-nitzschia species and draft genomes of ten additional Pseudo-nitzschia species, putative genomic integration sites for the dab genes in Pseudo-nitzschia species were explored. A putative breakpoint was observed in syntenic regions in the dab gene cluster-lacking Pseudo-nitzschia species, suggesting potential independent losses of dab genes. The breakpoints between this pair of conserved genes were also identified in some dab genes-possessing Pseudo-nitzschia species, suggesting that the dab gene clusters transposed to other loci after the initial integration. A "single acquisition, multiple independent losses (SAMIL)" model is proposed to explain the acquisition and evolution of the dab gene cluster in Pseudo-nitzschia species. A "single acquisition, multiple independent losses (SAMIL)" model is proposed to explain the acquisition and evolution of the domoic acid biosynthesis gene cluster in Pseudo-nitzschia species. [ABSTRACT FROM AUTHOR]

Fungal natural products (NPs), known for their potent bioactivities, can be utilized as human therapeutics and agrochemicals. These bioactive and structurally complex compounds are biosynthesized through condensation of monomeric building blocks to construct core scaffolds, followed by various modification steps. Recent studies have revealed that a unique class of enzymes from the NTF2‐like protein family plays important roles in the biosynthesis of complex fungal NPs. These NTF2‐like enzymes belong to a large group of related proteins that share a common fold with nuclear transport factor 2, and are capable of catalyzing various reactions. In this study, we summarize the recent progress in discovering and characterizing the catalytic functions of fungal‐derived NTF2‐like enzymes, including dehydratases, epimerases, isomerases, semipinacolases, pericyclases, and aldolases. These findings not only provide valuable insights into new catalytic reactions and mechanisms, but also offer opportunities to discover novel NPs and biocatalysts through genome mining. [ABSTRACT FROM AUTHOR]

Background: The prevalence of cognitive diseases, including Alzheimer's disease and other forms of dementia, poses a significant global health challenge due to the limited availability of effective therapeutic options. Recent years have witnessed a growing emphasis in research on the exploration of natural compounds and their derivatives as prospective therapeutic agents for cognitive impairments. Main body Xanthotoxin, a furanocoumarin compound derived from botanical sources, exhibits promising therapeutic promise in several neurological conditions such as depression, neuronal inflammation, Alzheimer's disease, vascular cognitive impairment, epilepsy, and Parkinson's disease. This potential stems from its notable neuroprotective, antioxidant, and anti-inflammatory characteristics. The present study offers a comprehensive examination of the acquisition of XAT from both natural sources and synthetic means. It delves into the significance of XAT in the treatment of cognitive disorders and delineates potential avenues for future research in the domain of XAT and cognitive disorders. Conclusion: Ongoing research and advancements in the field of XAT have the potential to enhance its use as a potent therapeutic intervention for cognitive impairments, consequently enhancing the holistic welfare of those afflicted by these incapacitating disorders. [ABSTRACT FROM AUTHOR]

DpAP2 is a transcription factor regulating carotenoid biosynthesis pathway. It was speculated that MeJA significantly decreased expression of DpAP2 gene, then the decreasing DpAP2 expression significantly inhibited expression of some key enzyme genes such as PSY, PDS and GGPS in carotenoid biosynthesis pathway. In contrast, it was speculated that GA3 significantly increased expression of DpAP2 gene, then the increasing DpAP2 expression significantly increased expression of some key enzyme genes such as PDS and GGPS in carotenoid biosynthesis pathway. To increase the content of carotenoid, we evaluated the effect of DpAP2 overexpression on carotenoid accumulation in D. parva. Transgenic D. parva showed a higher carotenoid content (3.18 mg/g DW) compared with control group (2.13 mg/g DW) at 9 d. The dosage effects of exogenous hormones MeJA and GA3 were found in D. parva cells treated with different concentrations of MeJA (10, 20, 50, 100 μM) and GA3 (10, 20, 50, 100 μM). The high concentrations of MeJA (10–100 μM) inhibited the accumulation of carotenoid, and the relative expression of DpAP2, PSY, PDS and GGPS decreased significantly. On the contrary, the relative expression of DpAP2, PDS and GGPS increased significantly when D. parva was treated with 10, 20, 50 and 100 μM GA3, which promoted the biosynthesis of carotenoid. Therefore, we inferred that there was a hierarchical regulation from hormone, transcription factor, key enzyme gene to carotenoid accumulation in carotenoid biosynthesis. Carotenoid biosynthesis was enhanced by DpAP2 overexpression (1.4930 fold of control) and exogenous substances such as GA3 (1.5889 fold of control), which laid a foundation for massive accumulation of carotenoids in microalgae. In the future, further studies were required to demonstrate the complex regulatory network. [ABSTRACT FROM AUTHOR]

SUMMARY Citral, a naturally occurring acyclic monoterpene aldehyde, is present in the essential oils of various plants, but only a few produce it in abundance. Despite its importance as a key aroma molecule, knowledge regarding the in‐planta biosynthesis of citral and its metabolic origin remains limited. Here, we have elucidated the functions of an alcohol dehydrogenase (CfADH1) and an aldoketo‐reductase (CfAKR2b) in citral biosynthesis in lemongrass (Cymbopogon flexuosus), one of the most cultivated aromatic crops for its citral‐rich essential oil. Expression of both CfADH1 and CfAKR2b showed correlation with citral accumulation in different developmental stages. Recombinant CfADH1 and CfAKR2b, despite their sequence unrelatedness, catalyzed citral formation from geraniol with NADP cofactor. Virus‐induced gene silencing in lemongrass and transient expression in lemon balm (Melissa officinalis) demonstrated the in‐planta involvement of CfADH1 and CfAKR2b in citral biosynthesis. While CfADH1 exhibited a dual cytosolic/plastidial localization, CfAKR2b was localized to the cytosol. This was supported by higher citral‐forming activity in the cytosolic fraction than in the chloroplast fraction of lemongrass leaf extract. Moreover, feeding lemongrass seedlings with inhibitors specific to the cytosolic mevalonate pathway and the plastidial methylerythritol phosphate pathway, combined with volatile profiling, supported the involvement of both pathways in citral formation. Taken together, our results indicate that high citral production has evolved in lemongrass through the recruitment of phylogenetically distant enzymes localized in both the cytosol and plastids. [ABSTRACT FROM AUTHOR]

Chlororaphens A and B are structurally unique non‐canonical C17 sesquiterpenoids from Pseudomonas chlororaphis that are made by two SAM‐dependent methyltransferases and a type I terpene synthase. This study addresses the mechanism of their formation in isotopic labelling experiments and DFT calculations. The results demonstrate an astonishing complexity with distribution of labellings within a cyclopentane core that is reversely connected to two acyclic fragments in chlororaphen A and B. In addition, the uptake of up to 14 deuterium atoms from D2O was observed. These findings are explainable by a repeated late stage multistep rearrangement sequence. The absolute configurations of the chlororaphens and their biosynthetic intermediates were elucidated in stereoselective labelling experiments. [ABSTRACT FROM AUTHOR]

Taxadiene is an important precursor of paclitaxel. However, its low yield in eukaryotic systems limits its biosynthesis. This study found that the low yield of taxadiene is likely due to the degradation of expressed taxadiene synthase (TS) in Saccharomyces cerevisiae. The TS expression degradation problem was improved by the knockout of protease PRB1, and the yield of taxadiene was increased by 97% from 19.8 mg L−1 to 39.2 mg L−1. Furthermore, multi-copy integration of the TS gene and enhancement of the geranylgeranyl diphosphate (GGPP) precursor pathway increased the taxadiene titer to 282.4 mg L−1 in a shake flask. Interestingly, enhancing TS expression also decreased the competitive synthesis of geranylgeraniol (GGOH). Finally, the taxadiene titer reached 878.5 mg L−1 after optimising the fed-batch fermentation, which is the highest taxadiene titer reported for eukaryotic microbes. This study alleviated the problems associated with the expression and degradation of heterologous proteins and provided an efficient and green strategy to produce complex natural compounds. [ABSTRACT FROM AUTHOR]

Both lanthanide-containing and fluorine-containing nanomaterials present challenging targets for microbial biosynthesis because these elements are toxic to most bacteria. Here, we overcome these challenges by using an Antarctic Shewanella baltica strain that tolerates these elements and report the first biosynthesis of lanthanide-doped fluoride nanoparticles (NPs) from them. NaYF4 NPs doped with Er3+/Yb3+ are prototypical lanthanide-based upconverting nanoparticles (UCNPs) with upconverted luminescence at visible wavelengths under infrared excitation. However, their synthesis employs high precursor concentrations, organic solvents, and elevated temperatures. Microbial biosynthesis offers a greener alternative but has not been explored for these materials. Here, we harness an extremophile S. baltica strain to biosynthesize UCNPs at room temperature, based upon its high tolerance for fluoride and lanthanide ions and the observation that tolerance of lanthanides increased in the presence of fluoride. Our biosynthesis produces electron-dense nanostructures composed of Na, Y, F, Yb, and Er in the bacterial periplasm, adhered to the outer cell membrane, and dispersed extracellularly, which exhibited up-converted emission under 980 nm excitation. This suggests that extracellular or periplasmic mineralization of lanthanides as fluorides protects the bacteria from lanthanide toxicity. Subsequent heating both enhanced upconverted emission from UCNPs and allowed observation of their crystallinity in transmission electron microscopy (TEM). This work establishes the first biosynthesis of NaYF4:Yb: Er UCNPs, advancing both nanotechnology and biotechnology. [ABSTRACT FROM AUTHOR]

Semen Ziziphi Spinosae (SZS) is a traditional Chinese herbal medicine widely used to treat insomnia and anxiety in clinical practice. Currently, the demand for SZS is increasing every year, but the production of wild SZS is unstable due to environmental factors. Grafting sour jujube scions onto sour jujube or jujube tree stocks can achieve a high production rate within a short period of time. However, the effects of grafting on the quality of SZS have not been reported. This study investigated the differences between wild-type and grafted SZS from three aspects: phenotype, chemical composition, and molecular mechanism. The findings revealed that the grafted specimens were generally larger in morphology and lighter in color than the wild-type samples. The dimensions of both the grafted specimens were generally larger than those of the wild specimens. The HPLC-ELSD results revealed that the three main chemical components in the grafted SZS, namely, spinosin, jujuboside A, and jujuboside B, had higher contents than their wild-type counterparts. Comprehensive transcriptome sequencing analysis and KEGG annotation revealed that DEG enrichment between grafted and wild-type SZS occurred mainly during stress resistance and rootstock scion healing. There were 23 DEGs that may encode enzymes involved in the biosynthetic pathway of flavonoids and 21 genes encoding terpenoid saponins. Further investigation revealed that the expression of the genes C4H, CHS, CHI, and F3'5'H in the flavonoid biosynthesis pat.hway and HMGR, MVK, MVD, and FPPS in the saponin biosynthesis pathway accounted for the difference in quality between grafted and wild SZS. Furthermore, WGCNA identified 15 core genes related to medicinal ingredients between grafted and wild SZS. These results provide support for further research on the differences in the quality of medicinal ingredients between grafted and wild SZS. [ABSTRACT FROM AUTHOR]

N-butanol is well known to be a flammable and harmful liquid that is a potential threat to human health and property. Therefore, it is important to monitor the concentration of n-butanol in the surroundings. The need for highly efficient toxic gas detection is urgent and has been driving the research on gas sensors for practical applications. Molybdenum disulfide (MoS2) has been attracting significant interest for gas detection at room temperature. Herein, we report biofunctionalized magnetic nanoparticles incorporated MoS2 for sensing n-butanol. The biosynthesized magnetite nanoparticles (CT-Fe3O4) were synthesized by the addition of Cinnamomum Tamala (CT) leaf extract, and subsequently, the nanocomposite was synthesized using a hydrothermal method. Highly sensitive sensors based on MoS2-CT-Fe3O4 were fabricated and tested for sensing different concentrations of n-butanol. The nanocomposites showed a good sensing performance (Δ R/Rair %) of 72% towards 20 ppm of n-butanol, indicating the potential use of MoS2-CT-Fe3O4 nanocomposite for sensing n-butanol at room temperature. [ABSTRACT FROM AUTHOR]

Ginsenoside Ro, as one of the few oleanane-type ginsenosides, is well known for its unique molecular structure and biological activities. Currently, research on the biosynthesis of ginsenoside Ro is still in its early stages. Therefore, the establishment of a new ginsenoside Ro cell factory is of great significance for the in-depth development and utilization of genes related to ginsenoside Ro synthesis, as well as for the exploration of pathways to obtain ginsenoside Ro. In this study, we cloned endogenous constitutive promoters, terminators, and other genetic elements from S. cerevisiae BY4741. These elements were then sequentially assembled with the uridine diphosphate glucuronic acid transferase gene identified in our previously study (PgUGAT252645) and several other reported key enzyme genes, to construct DNA fragments used for integration into the genome of S. cerevisiae BY4741. By sequentially transferring these DNA fragments into chemically competent cells of engineering strains and conducting screening and target product detection, we successfully constructed an engineered S. cerevisiae strain (BY-Ro) for ginsenoside Ro biosynthesis using S. cerevisiae BY4741 as the host cell. Strain BY-Ro produced 253.32 μg/L of ginsenoside Ro under optimal fermentation conditions. According to subsequent measurements and calculations, this equates to 0.033 mg/g DCW, corresponding to approximately 31% of the ginsenoside Ro content found in plant samples. This study not only included a deeper investigation into the function of PgUGAT252645 but also provides a novel engineering platform for ginsenoside Ro biosynthesis. [ABSTRACT FROM AUTHOR]

SUMMARY: Astragaloside IV is a significant chemical component derived from the medicinal plant Astragalus membranaceus. Despite the characterization of several glycosyltransferases from A. membranaceus, the complete biosynthetic pathway of astragaloside IV has not been fully elucidated. In this study, we propose a biosynthetic pathway for astragaloside IV that involves a sequence of oxidation–reduction reactions. The biosynthesis pathway from cycloastragenol to astragaloside IV encompasses four key steps: C‐3 oxidation, 6‐O‐glucosylation, C‐3 reduction, and 3‐O‐xylosylation. We identified a hydroxysteroid dehydrogenase AmHSD1 from A. membranaceus. AmHSD1 catalyzes the C‐3 oxidation of cycloastragenol, yielding cycloastragenol‐3‐one, and the C‐3 reduction of cycloastragenol‐3‐one‐6‐O‐glucoside, resulting in cycloastragenol‐6‐O‐glucoside. Additionally, the glycosyltransferases AmGT8 and AmGT1, previously reported by our groups, were identified as catalyzing the 6‐O‐glucosylation and 3‐O‐xylosylation steps, respectively. Astragaloside IV was successfully synthesized in transient expression in Nicotiana benthamiana using the combination of AmHSD1, AmGT8 and AmGT1. These results support the proposed four‐step biosynthetic pathway and suggest that AmHSD1 probably plays a crucial role in the biosynthesis of astragaloside IV within A. membranaceus. [ABSTRACT FROM AUTHOR]

The deprotonation–reprotonation sequence introduces additional cyclization branches in terpene biosynthesis. However, the underlying mechanism remains poorly understood. In this study, we employed a combined approach of molecular dynamics (MD) simulations and site-directed mutagenesis on astellifadiene synthase EvAS from Emericella variecolor to investigate the role of a protonated S85 residue. This residue acts as a catalytic acid, previously unreported, that facilitates the reprotonation step in astellifadiene biosynthesis. Mutating S85 led to the production of a new tricyclic sesterterpene. [ABSTRACT FROM AUTHOR]

Chloroplast-encoded multi-span thylakoid membrane proteins are crucial for photosynthetic complexes, yet the coordination of their biogenesis remains poorly understood. To identify factors that specifically support the cotranslational biogenesis of the reaction center protein D1 of photosystem (PS) II, we generated and affinity-purified stalled ribosome-nascent chain complexes (RNCs) bearing D1 nascent chains. Stalled RNCs translating the soluble ribosomal subunit uS2c were used for comparison. Quantitative tandem-mass spectrometry of the purified RNCs identified around 140 proteins specifically associated with D1 RNCs, mainly involved in protein and cofactor biogenesis, including chlorophyll biosynthesis, and other metabolic pathways. Functional analysis of STIC2, a newly identified D1 RNC interactor, revealed its cooperation with chloroplast protein SRP54 in the de novo biogenesis and repair of D1, and potentially other cotranslationally-targeted reaction center subunits of PSII and PSI. The primary binding interface between STIC2 and the thylakoid insertase Alb3 and its homolog Alb4 was mapped to STIC2's β-sheet region, and the conserved Motif III in the C-terminal regions of Alb3/4. Synopsis: The biogenesis and maintenance of photosynthetic complexes requires precise coordination of cotranslational maturation, folding, targeting and insertion of their plastid-encoded subunits. This work offers insight into the interactome of photosystem II reaction center-specific ribosome-nascent chain complexes, and identifies a role for STIC2 in their cotranslational protein sorting. Proteins from metabolic, biogenesis, and protein processing pathways associate with D1-translating ribosomes. Knock-out of STIC2 and the targeting factor cpSRP54 in Arabidopsis causes sensitivity to high light and low accumulation of photosystem subunits. STIC2 partially associates with ribosomes and affects chloroplast translation. The C-terminal motif III of the thylakoid membrane proteins Alb3 and Alb4 mediates their interaction within the β-sheet region of STIC2. The chloroplast protein STIC2 associates with ribosomes translating the photosystem II reaction center protein D1 and supports insertion into the thylakoid membrane. [ABSTRACT FROM AUTHOR]

Bioactive dimeric (pre‐)anthraquinones are ubiquitous in nature and are found in bacteria, fungi, insects, and plants. Their biosynthesis via oxidative phenol coupling (OPC) is catalyzed by cytochrome P450 enzymes, peroxidases, or laccases. While the biocatalysis of OPC in molds (Ascomycota) is well‐known, the respective enzymes in mushroom‐forming fungi (Basidiomycota) are unknown. Here, we report on the biosynthesis of the atropisomers phlegmacin A1 and B1 of the mushroom Cortinarius odorifer. The biosynthesis of these unsymmetrically 7,10'‐homo‐coupled dihydroanthracenones was heterologously reconstituted in the mold Aspergillus niger. Methylation of the parental monomer atrochrysone to its 6‐O‐methyl ether torosachrysone by the O‐methyltransferase CoOMT1 precedes the regioselective homocoupling to phlegmacin, catalyzed by the enzyme CoUPO1 annotated as an "unspecific peroxygenase" (UPO). Our results reveal an unprecedented UPO reaction, thereby expanding the biocatalytic portfolio of oxidative phenol coupling beyond the commonly reported enzymes. The results show that Basidiomycota use peroxygenases to selectively couple aryls independently of and convergently to any other group of organisms, emphasizing the central role of OPC in natural processes. [ABSTRACT FROM AUTHOR]

Background: MYB transcription factors regulate anthocyanin biosynthesis across numerous plant species. However, comprehensive genome-wide investigations regarding the R2R3-MYB gene family and its involvement in regulating anthocyanin biosynthesis in the red and white fruit color morphs of Fragaria pentaphylla remain scarce. Results: A total of 101 FpR2R3-MYB genes were identified from the F. pentaphylla genome and were divided into 34 subgroups based on phylogenetic analysis. Gene structure (exon/intron) and protein motifs were particularly conserved among the FpR2R3-MYB genes, especially members within the same subgroup. The FpR2R3-MYB genes were distributed over seven F. pentaphylla chromosomes. Analysis of gene duplication events revealed five pairs of tandem duplication genes and 16 pairs of segmental duplication genes, suggesting that segmental duplications are the major pattern for expansion of the FpR2R3-MYB gene family expansion in F. pentaphylla. Cis-regulatory elements of the FpR2R3-MYB promoters were involved in cellular development, phytohormones, environmental stress and photoresponse. Based on the analysis of the FpR2R3-MYB gene family and transcriptome sequencing (RNA-seq) data, FpMYB9 was identified as a key transcription factor involved in the regulation of anthocyanin synthesis in F. pentaphylla fruits. The expression of FpMYB9 increases significantly during the ripening stage of red fruits, as confirmed by reverse transcription quantitative real-time PCR. In addition, subcellular localization experiments further confirmed the nuclear presence of FpMYB9, supporting its role as a transcription factor involved in anthocyanin biosynthesis. Conclusion: Our results showed that the FpR2R3-MYB genes are highly conserved and play important roles in the anthocyanin biosynthesis in F. pentaphylla fruits. Our results also provide a compelling basis for further understanding of the regulatory mechanism underlying the role of FpMYB9 in anthocyanin formation in F. pentaphylla fruits. [ABSTRACT FROM AUTHOR]

Introduction: Carbohydrate compounds serve multifaceted roles, from energy sources to stress protectants, found across diverse organisms including bacteria, fungi, and plants. Despite this broad importance, the molecular genetic framework underlying carbohydrate biosynthesis pathways, such as starch, sucrose, and glycolysis/gluconeogenesis in Salvia guaranitica, remains largely unexplored. Methods: In this study, the Illumina-HiSeq 2500 platform was used to sequence the transcripts of S. guaranitica leaves, generating approximately 8.2 Gb of raw data. After filtering and removing adapter sequences, 38 million reads comprising 210 million high-quality nucleotide bases were obtained. De novo assembly resulted in 75,100 unigenes, which were annotated to establish a comprehensive database for investigating starch, sucrose, and glycolysis biosynthesis. Functional analyses of glucose-6-phosphate isomerase (SgGPI), trehalose-6-phosphate synthase/phosphatase (SgT6PS), and sucrose synthase (SgSUS) were performed using transgenic Arabidopsis thaliana. Results: Among the unigenes, 410 were identified as putatively involved in these metabolic pathways, including 175 related to glycolysis/gluconeogenesis and 235 to starch and sucrose biosynthesis. Overexpression of SgGPI, SgT6PS, and SgSUS in transgenic A. thaliana enhanced leaf area, accelerated flower formation, and promoted overall growth compared to wild-type plants. Discussion: These findings lay a foundation for understanding the roles of starch, sucrose, and glycolysis biosynthesis genes in S. guaranitica, offering insights into future metabolic engineering strategies for enhancing the production of valuable carbohydrate compounds in S. guaranitica or other plants. [ABSTRACT FROM AUTHOR]

The basic helix-loop-helix (bHLH) transcription factors play crucial roles in various processes, such as plant development, secondary metabolism, and response to biotic/abiotic stresses. Sophora flavescens is a widely used traditional herbal medicine in clinical practice, known for its abundant flavonoids as the main active compounds. However, there has been no comprehensive analysis of S. flavescens bHLH (SfbHLH) gene family reported currently. In this study, we identified 167 SfbHLH genes and classified them into 23 subfamilies based on comparative genomics and phylogenetic analysis. Furthermore, widespread duplications significantly contributed to the expansion of SfbHLH family. Notably, SfbHLH042 was found to occupy a central position in the bHLH protein-protein interaction network. Transcriptome analysis of four tissues (leaf, stem, root and flower) revealed that most SfbHLH genes exhibited high expression levels exclusively in specific tissues of S. flavescens. The integrated analysis of transcriptomics and metabolomics during pod development stages revealed that SfbHLH042 may play a central role in connecting SfbHLH genes, flavonoids, and key enzymes involved in the biosynthesis pathway. Moreover, we also checked the expression of 8 SfbHLH genes using RT-qPCR analysis to realize the expression profiles of these genes among various tissues at different cultivated periods and root development. Our study would aid to understand the phylogeny and expression profile of SfbHLH family genes, and provide a promising candidate gene, SfbHLH042, for regulating the biosynthesis of flavonoids in S. flavescens. [ABSTRACT FROM AUTHOR]

Tetrapyrroles such as heme, chlorophyll, and vitamin B12 are essential for various metabolic pathways. They derive from 5-aminolevulinic acid (5-ALA), which can be synthesized by a single enzyme (5-ALA synthase or AlaS, Shemin pathway) or by a two-enzyme pathway. The genomes of some bacteriophages from aquatic environments carry various tetrapyrrole biosynthesis genes. Here, we analyze available metagenomic datasets and identify alaS homologs (viral alaS, or valaS) in sequences corresponding to marine and freshwater phages. The genes are found individually or as part of complete or truncated three-gene loci encoding heme-catabolizing enzymes. Amino-acid sequence alignments and three-dimensional structure prediction support that the valaS sequences likely encode functional enzymes. Indeed, we demonstrate that is the case for a freshwater phage valaS sequence, as it can complement an Escherichia coli 5-ALA auxotroph, and an E. coli strain overexpressing the gene converts the typical AlaS substrates glycine and succinyl-CoA into 5-ALA. Thus, our work identifies valaS as an auxiliary metabolic gene in phage sequences from aquatic environments, further supporting the importance of tetrapyrrole metabolism in bacteriophage biology. Tetrapyrroles such as heme and chlorophyll, which are essential for various metabolic pathways, are synthesized from 5-aminolevulinic acid (5-ALA). Here, the authors identify functional 5-ALA synthase genes in bacteriophage sequences from aquatic environments, thus highlighting the importance of tetrapyrrole metabolism in phage biology. [ABSTRACT FROM AUTHOR]

Color is the most prominent factor in any marketable product. Among microorganisms, Pseudomonas spp. produces four different types of pigments. The aim of this study is biosynthesis and optimization of pyoverdine from locally isolated Pseudomonas aeruginosa. Response surface methodology (RSM) was used to optimize two growth parameters, i.e., temperature (30–40 ℃) and pH (5–8). RSM predicted maximum yield of pyoverdine at pH 7 and temperature 37℃. Optimal growth media and incubation time required for pigment production was analyzed by spectroscopy. For this, three culture media (nutrient broth, King's B, and synthetic citrate media) were inoculated with P. aeruginosa and incubated at 37℃ for 24–120 h. Maximum optical density 1.94 (in nutrient broth) at 420 nm indicated maximum production of pyoverdine, and time recorded for maximum production was 120 h. Growth of P. aeruginosa on nutrient broth, pH 7, incubation time 120 h at 37℃ yielded 2.5 g/L pyoverdine; that was extracted using chloroform. Spectroscopic analysis revealed presence of a chromophore that emits maximum light at 400 nm and thin-layer chromatography performed using n-butanol, acetic acid, and water 3:2:1 as solvent system indicated exhibition of florescent under UV lamp of 354 nm. Amine stretch (3232.46 cm−1), carboxyl group (1628 cm−1), and amide group (1402 cm−1) were indicated by FT-IR, and peaks obtained from NMR spectra at 7.888 ppm, 7.1 ppm, and 7.26 ppm represent 1.6 proton of aromatic chain H-4, H-5, and H-8 chromophore 3a that has been derived from 2,3-diamino-hydroxyquinoline. All of these findings demonstrate that Pseudomonas aeruginosa has the capacity to manufacture pyoverdine under the aforementioned ideal cultivation circumstances. [ABSTRACT FROM AUTHOR]

The aim of this work was to synthesize zinc oxide nanoparticles (ZnO NPs) using guava leaf extract as a biogenic substance that facilitates NPs production. The obtained ZnO was characterized using FTIR, XRD, SEM, and UV-Vis techniques and assayed for its antibacterial and hemolytic effects. The results revealed a hexagonal phase with a crystallite size of 25.08 nm and an optical bandgap of 3.33 eV. Bioactivity studies indicated dose-dependent activity with comparable antibacterial activity to gentamicin standard drug, higher against S. aureus (gram-positive) than E. coli and K. pneumoniae (gram-negative) bacteria. The hemocompatibility test against erythrocytes confirmed a nontoxic substance up to 500 μg/mL at which the hemolysis value, under the experimental condition, was 3.2%. These results support the benefit of the synthesized guava extract-mediated ZnO, with a perspective application in electrochemical devices and as a safe antibacterial agent. [ABSTRACT FROM AUTHOR]

This study reports the biosynthesis of FeMn2O4 nanocomposite (NC) using an aqueous leaf extract of Artemisia. The FeMn2O4 NC was characterized by zeta potential, SEM, XRD, and FTIR. X-ray diffraction analysis confirmed that the biosynthesized FeMn2O4 NC has a cubic crystal nature with a crystallite size of 28.45 nm. Scanning electron microscopy images showed that the FeMn2O4 NC has a spherical shape. The optical bandgap energy of the FeMn2O4 NC was estimated to be approximately 2.94 eV for direct bandgap and 1.27 eV for indirect bandgap. The photocatalytic activity of the FeMn2O4 NC was evaluated for the degradation of amoxicillin and cephalexin antibiotics under sunlight irradiation, resulting in a degradation efficiency of 99% for both drugs. The FeMn2O4 NC also exhibited excellent degradation efficiency against Congo Red (CR) and Methylene Blue (MB) dyes with about 83.23% and 100%, respectively, after just 40 min. The reaction kinetic calculations showed that the absorption of both dyes and antibiotics by the adsorbent followed a pseudo-first-order model. The equilibrium isotherms revealed that the amoxicillin and cephalexin absorption process through the synthesized magnetic nanocomposite was consistent with the Langmuir model. These findings suggest that the FeMn2O4 NC can serve as a promising absorbent for the removal of amoxicillin and cephalexin antibiotics as well as MB and RC dyes from aqueous solutions. [ABSTRACT FROM AUTHOR]

Poly(lactate-co-3-hydroxybutyrate) [P(LA-co-3HB)] is a high-molecular-weight biomaterial with excellent biocompatibility and biodegradability. In this study, the properties of P(LA-co-3HB) were examined and found to be affected by its lactate fraction. The efficiency of lactyl-CoA biosynthesis from intracellular lactate significantly affected the microbial synthesis of P(LA-co-3HB). Two CoA transferases from Anaerotignum lactatifermentans and Bacillota bacterium were selected for use in copolymer biosynthesis from 11 candidates. We found that cotAl enhanced the lactate fraction by 31.56% compared to that of the frequently used modified form of propionyl-CoA transferase from Anaerotignum propionicum. In addition, utilizing xylose as a favorable carbon source and blocking the lactate degradation pathway further enhanced the lactate fraction to 30.42 mol% and 52.84 mol%, respectively. Furthermore, when a 5 L bioreactor was used for fermentation utilizing xylose as a carbon source, the engineered strain produced 60.60 wt% P(46.40 mol% LA-co-3HB), which was similar to the results of our flask experiments. Our results indicate that the application of new CoA transferases has great potential for the biosynthesis of other lactate-based copolymers. [ABSTRACT FROM AUTHOR]

Polycystic Ovary Syndrome (PCOS) is a widespread and complex hormonal disorder occurs in women of reproductive age, characterized by hormonal imbalances and ovarian dysfunction. Current approaches to treating PCOS often address specific symptoms, highlighting the demand for innovative therapeutic agents that can tackle its multifaceted nature. The present study endeavors to investigate the potential of new chromen‐2‐one derivatives in the management of PCOS. A total of 30 derivatives have been synthesized and evaluated for their in vitro inhibitory effects on 5‐α reductase and antioxidant activities. Based on the promising in vitro activity and acute toxicity profile of 4‐methoxy‐N‐(3‐(4‐methoxyphenyl)‐2‐oxo‐2H‐chromen‐6‐yl) benzamide (29), it was selected for subsequent in vivo investigation in experimental animal models of PCOS. The study also includes molecular interaction analysis through docking and dynamic studies of compound (29). [ABSTRACT FROM AUTHOR]