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The transcription factor SbWRKY6 confers cadmium tolerance via activating SbPLAC8-17 expression in sorghum.

Cadmium (Cd) is a widespread environmental pollutant that severely threatens crop productivity and food safety. However, the regulatory mechanisms underlying Cd detoxification and tolerance in sorghum remain largely elusive. Herein, we functionally characterized SbWRKY6, a Cd‑induced WRKY transcription factor that localizes to the nucleus and functions as a transcriptional activator. Stable overexpression of SbWRKY6 significantly enhanced Cd tolerance in sorghum, as evidenced by improved growth performance, mitigated oxidative damage, and decreased Cd concentration in plant tissues, whereas silencing of SbWRKY6 resulted in a Cd-hypersensitive phenotype with exacerbated toxicity symptoms. Mechanistically, we identified SbPLAC8-17, a member of the Plant Cadmium Resistance (PCR)/PLAC8 family, as a critical downstream target of SbWRKY6. Heterologous expression of SbPLAC8-17 functionally complemented the Cd‑sensitive phenotype of the yeast mutant ∆ycf1 and reduced intracellular Cd accumulation. Further yeast one-hybrid (Y1H), electrophoretic mobility shift assay (EMSA), and dual-luciferase reporter (Dual-LUC) assays confirmed that SbWRKY6 directly binds to the SbPLAC8-17 promoter and transcriptionally activates its expression. In vivo silencing of SbPLAC8-17 significantly impaired cellular Cd²⁺ efflux and aggravated Cd toxicity in sorghum. Additionally, the rapid Cd-induced transcriptional upregulation of SbMPK3 and its direct physical interaction with SbWRKY6 suggest a potential upstream regulatory module that remains to be functionally validated. Collectively, this study elucidates a novel SbWRKY6‑SbPLAC8-17 transcriptional cascade that positively regulates Cd tolerance by facilitating Cd²⁺ efflux, providing promising genetic targets for phytoremediation and molecular breeding of safe sorghum cultivars for Cd-contaminated fields.

Sorghum

MmoD and MmoG Are Crucial for the Synthesis of Soluble Methane Monooxygenase in Methanotrophs.

Soluble methane monooxygenase (sMMO) from methanotrophs has been extensively investigated for decades. However, major knowledge gaps persist regarding the synthesis mechanism of sMMO, particularly concerning the ambiguous roles of mmoD and mmoG in the sMMO gene cluster. Here, the functions of mmoD and mmoG were investigated in a model methanotrophic strain, Methylotuvimicrobium buryatense 5GB1C. Both genes were found to be essential for the functional expression of sMMO. Genetic and biochemical data supported the hypothesis that MmoG acts as a folding chaperone for both MmoX and MmoR, while MmoD serves as an assembly chaperone for the hydroxylase component. The functional expression of sMMO in Escherichia coli was achieved in an mmoD- and mmoG-dependent manner. In addition, deletion of mmoD dramatically reduced the transcription of the sMMO cluster in M. buryatense 5GB1C, implying that MmoD may regulate the sMMO cluster via an unknown mechanism. Knockout of neither mmoD nor mmoG abolished the essential feature of "copper switch", indicating that they do not serve as the initial regulators of "copper switch". These results demonstrate the crucial roles of mmoD and mmoG in sMMO synthesis and offer new insights into heterologous expression of sMMO.

Oxygenases

Unveiling Aziridine-Containing Natural Products by Genomic and Spectroscopic Approaches.

Aziridine-containing natural products are prized for their potent bioactivities, yet their scarcity and poorly understood biosynthesis have limited systematic exploration. Here, we address this by integrating genome mining with a 1H-13C coupled HSQC metabolomic approach that exploits the distinctive NMR signatures of aziridines, enabling their direct detection from complex extracts. This strategy unveiled the desertolides, the first macrolides incorporating a rare terminal 2-methyl-aziridine-2-carboxylate moiety. Genetic and isotopic studies identified a dedicated biosynthetic subcluster (desA-desN) that assembles and installs this unit from glutamate, and heterologous expression confirmed the self-sufficiency of this subcluster. Direct MS evidence reveals the aziridine moiety covalently bound to the active-site Cys113 of DesN, establishing this KAS III homolog as the first dedicated aziridine-transferase and a promising tool for polyketide engineering. Bioinformatic analysis uncovered over 50 biosynthetic gene clusters, suggesting that this aziridine-associated biosynthetic logic may be more widespread than currently appreciated. This work establishes a tractable platform for the targeted discovery and engineered biosynthesis of aziridine-containing natural products, opening this underexplored pharmacophore to systematic interrogation.

Aziridines

R2R3-MYB transcription factor MYB113 specifically regulates anthocyanin accumulation in Lycium ruthenicum.

LrMYB113 drives anthocyanin biosynthesis in Lycium ruthenicum by forming an MBW complex and directly activating LrDFR and LrANS promoters, providing a genetic target for enhancing flavonoid production. Lycium ruthenicum Murray (black goji berry), a Solanaceae medicinal plant, is valued for its high flavonoid content. However, the transcriptional regulation of flavonoid biosynthesis in L. ruthenicum remains unclear, hindering its pharmaceutical development. Here, we identified and characterized LrMYB113, an R2R3-MYB transcription factor, as a key regulator of anthocyanin biosynthesis in L. ruthenicum. Phylogenetic analysis grouped LrMYB113 into the anthocyanin-associated S6 subgroup of MYBs. Heterologous expression of LrMYB113 in tobacco induced pigment accumulation and upregulated anthocyanin pathway genes. LrMYB113 overexpression in L. ruthenicum hairy roots enhanced accumulation of four acylated anthocyanins and activated anthocyanin pathway genes. Yeast two-hybrid and bimolecular fluorescence complementation assays showed LrMYB113 interacts with bHLHs (LrJAF13/LrAN1b) and WD40 (LrAN11) to form an MBW complex. Promoter binding and transactivation assays demonstrated LrMYB113 directly binds to and activates LrDFR and LrANS promoters. Dual-luciferase assays showed LrMYB113 alone strongly activates LrDFR and LrANS promoters; MBW complexes enhanced activity compared to individual bHLH/WD40 but not to LrMYB113 alone. Our findings identify LrMYB113 as a critical regulator of anthocyanin biosynthesis in L. ruthenicum, shedding light on flavonoid molecular mechanisms and supporting genetic improvement for pharmaceutical use.

Anthocyanins

Decoding the distribution, structure-function-redox potential relationship and recent advances in fungal laccases: a systematic approach.

Laccases, categorized as multicopper oxidases, are recognized for their multifaceted roles in ecosystems and their utility in diverse industrial applications. Laccases from higher fungi, specifically Ascomycota and Basidiomycota, have garnered significant research interest due to their elevated redox potentials and their capacity to degrade lignin in decaying wood, alongside other industrial uses. Here, we have conducted a comprehensive and systematic analysis on fungal laccases using Web of Science, Scopus, PubMed, and ScienceDirect. The genomic distribution, phylogenetic affiliation, and structural organization of laccase-encoding genes in higher fungal species were investigated, as were the catalytic mechanisms of the corresponding enzymes. Additionally, the study explores the correlation between structural domains and redox potential, as well as the impact of post-translational modifications like glycosylation on enzyme activity. Furthermore, the recent advancements in laccase engineering, employing strategies such as rational design, directed evolution, and heterologous expression are discussed. The review also explores the scope of "artificial intelligence and machine learning" in deducing the structure-function relationships, optimizing codon usage, predicting signal peptides, enhancing enzymatic performance, and developing host-specific genetic engineering techniques is also discussed for tailoring fungal laccases to meet the demands of industrial biocatalysis for improved activity and stability.

Laccase

Obesity-enriched gut microbe degrades myo-inositol and promotes lipid absorption.

Numerous studies have reported critical roles for the gut microbiota in obesity. However, the specific microbes that causally contribute to obesity and the underlying mechanisms remain undetermined. Here, we conducted shotgun metagenomic sequencing in a Chinese cohort of 631 obese subjects and 374 normal-weight controls and identified a Megamonas-dominated, enterotype-like cluster enriched in obese subjects. Among this cohort, the presence of Megamonas and polygenic risk exhibited an additive impact on obesity. Megamonas rupellensis possessed genes for myo-inositol degradation, as demonstrated in vitro and in vivo, and the addition of myo-inositol effectively inhibited fatty acid absorption in intestinal organoids. Furthermore, mice colonized with M. rupellensis or E. coli heterologously expressing the myo-inositol-degrading iolG gene exhibited enhanced intestinal lipid absorption, thereby leading to obesity. Altogether, our findings uncover roles for M. rupellensis as a myo-inositol degrader that enhances lipid absorption and obesity, suggesting potential strategies for future obesity management.

Inositol

Functional identification of the key gene Eh-fadB in nicosulfuron degradation by Enterobacter hormaechei ES1 based on multi-omics and enzymatic characterization.

Nicosulfuron is a sulfonylurea herbicide with residues that pose ecological risks in agricultural soils. Here we elucidated the degradation mechanism of Enterobacter hormaechei ES1 through whole-genome sequencing, transcriptomics, metabolomics, gene knockout, heterologous expression, and soil bioremediation assays. Under nicosulfuron stress, ES1 upregulated antioxidant enzymes including SOD, POD, and CAT, along with glutathione synthesis, to scavenge excess reactive oxygen species. HPLC-TOF-MS identified degradation intermediates such as ADMP and ASDM, indicating initial cleavage of the sulfonylurea bridge. Integrated multi-omics prioritized Eh-fadB, encoding a fatty acid β-oxidation multifunctional enzyme, as a novel degradative gene. Targeted knockout of Eh-fadB reduced nicosulfuron degradation from 87.6% to 37.04%, while genetic complementation restored nearly full activity. Purified Eh-FadB directly converted nicosulfuron, with optimal performance at 30 °C and pH 5-6; its activity was enhanced by Na+ and Pb2+ but inhibited by Fe3+. Molecular docking and dynamics identified His-450 and Asn-427 as key residues for substrate binding. In contaminated soil, inoculation with ES1 reduced nicosulfuron content within 21 days and promoted recovery of dehydrogenase and urease activities. This study provides the first genetic and biochemical evidence that a FadB-type enzyme participates in nicosulfuron catabolism, supporting sulfonylurea bridge cleavage and its potential for soil bioremediation.

Eh-fadB

Biochemical analysis of the TPS-b subfamily reveals a cineole-centered monoterpene biosynthetic module in Medicago truncatula.

Terpenoids constitute one of the largest and most structurally diverse classes of plant specialized metabolites, with diversity generated by terpene synthases (TPSs) and downstream tailoring enzymes. In Medicago truncatula, the TPS-b subfamily comprises five putative synthases, two of which are embedded within a previously uncharacterized genomic locus containing a cytochrome P450 (CYP) and a BAHD-type acyltransferase. Here, we present a comprehensive biochemical analysis of the M. truncatula TPS-b subfamily and define a cineole-centered monoterpene biosynthetic module. Heterologous expression and in vitro assays with multiple prenyl diphosphate substrates revealed three catalytically active TPS-b enzymes with distinct substrate preferences and product profiles. MtTPS4 functions as a dedicated (E)-β-ocimene synthase, whereas MtTPS15 exhibits substrate-dependent bifunctionality, producing (E)-β-ocimene from geranyl diphosphate and α-farnesene from farnesyl diphosphate. MtTPS36 generates 1,8-cineole as the predominant product alongside α-terpineol from geranyl and neryl diphosphate. Genome analysis revealed that MtTPS36 is colocalized with a cytochrome P450 belonging to the CYP736 family. Biochemical characterization of this CYP identified a previously undescribed plant cineole hydroxylase that catalyzes oxidation of 1,8-cineole to yield 2α-hydroxy-1,8-cineole (also known as 2-exo-hydroxy-1,8-cineole), establishing a TPS-CYP biosynthetic module. These results define the gene-to-metabolite relationships within the TPS-b subfamily in M. truncatula and expand the known enzymatic biosynthetic capacity underlying oxygenated monoterpene biosynthesis in plants.

1,8-Cineole

Biosynthesis and Glycosylation of Antarlides, the Polyene Macrolides Possessing Androgen Receptor Antagonistic Activity.

Antarlides (ATLs) are tetraene macrolides discovered from Streptomyces spp. They demonstrated excellent antagonist activities toward mutated androgen receptors (ARs) related to the drug resistances in AR-targeted prostate cancer treatment. Herein, a biosynthetic gene cluster (BGC) of type I modular polyketide synthases (PKSs) from S. conglobatus ATCC 31005 was verified to be responsible for the biosynthesis of ATLs in the heterologous host S. lividans SBT5. The atl BGC was also activated in situ in S. conglobatus by equipping a strong promoter for the PKS genes operon. Unexpectedly, a new glycosylated product, ATL D1, was produced in the heterologous expression. ATL D1 was also generated in the S. conglobatus mutant bearing activated atl BGC through the introduction of a GT1 family glycosyltransferase gene mgt from S. lividans. Enzymatic analysis showed that the protein MGT catalyzed the glycosylation of ATL D to yield ATL D1 by attaching a β-d-glucose to the C11-hydroxyl position. Moreover, site-directed mutation of MGT resulted in an iterative glycosylation to yield ATL D2 bearing a disaccharide at the C11-hydroxyl. These results offer a platform for constructing efficient biosynthetic pathway of ATLs, and the O-glycosylation could be applied to improve the pharmaceutical properties of ATLs.

Glycosylation

Biosynthesis of Crinipellin Diterpenes in Mushroom Marasmius fiardii PR-910.

Crinipellins are a distinctive family of 5/5/5/5 tetracyclic diterpenoids previously reported exclusively from mushrooms of the genus Crinipellis. Despite extensive synthetic studies, the biosynthetic machinery responsible for crinipellin formation has remained elusive. Here, we identify the crinipellin biosynthetic gene cluster (mfd) from the mushroom Marasmius fiardii PR-910, a member of the family Marasmiaceae to which Crinipellis also belongs, although M. fiardii PR-910 itself has not been previously reported to produce crinipellins. Using a combination of site-directed mutagenesis guided by an AlphaFold3-generated structural model, stable isotope-labeling studies, density functional theory (DFT) calculations, and ab initio molecular dynamics (AIMD) simulations, the cyclization mechanism of the diterpene synthase MfdB, which constructs the fused tetraquinane scaffolds 1 and 2, was elucidated. Mutagenesis of MfdB uncovered cryptic cyclization pathways that generate structurally diverse diterpenes, including unprecedented bridged and rearranged diterpene skeletons (4-6), whose formation is supported by computational analyses, and further revealed an unusual arginine-rich diphosphate-binding architecture. Heterologous expression studies in Aspergillus oryzae and Saccharomyces cerevisiae established the oxidative functions of the cytochrome P450 enzymes MfdC, MfdD, and MfdE, leading to the production of 19 previously undescribed oxidized metabolites (16-34). Notably, MfdE, a member of the largely unexplored CYP_FUM15-like subfamily, catalyzes an unusual oxidative demethylation through C-C bond cleavage, expanding the known catalytic repertoire of fungal cytochrome P450 enzymes. Collectively, this work establishes the biosynthetic logic of crinipellin formation, reveals how terpene synthase plasticity generates cryptic diterpene scaffolds, and demonstrates how oxidative tailoring by multiple cytochrome P450 enzymes drives diterpene scaffold diversification.

Diterpenes

A multifunctional sesquiterpene synthase integrates with cytochrome P450s to reinforce the terpenoid defense network in maize.

Terpenoids, the largest and most structurally diverse class of plant natural products, play essential roles in maize defense and ecological interactions. In this study, we identified and functionally characterized a sesquiterpenoid-based defense pathway in maize centered on α-santalenoic acid, a pathogen-inducible sesquiterpenoid antibiotic. Using a combination of metabolite-based genome-wide association studies (mGWAS), linkage mapping, and heterologous expression assays, we identified ZmTPS9 as a multiproduct terpene synthase that primarily produces α-santalene and β-bisabolene. Sequence analysis and site-directed mutagenesis revealed that threonine at position 413 is critical for enzyme activity, with its deletion resulting in a complete loss of enzyme activity. The sesquiterpene hydrocarbons produced by ZmTPS9 are further oxidized by three cytochrome P450 monooxygenases, ZmCYP71Z16, ZmCYP71Z18, and ZmCYP71Z19, to yield antimicrobial metabolites including α-santalenoic acid, zealexin D1 (ZD1), and zealexin D2 (ZD2). Together, these findings demonstrate a convergent biosynthetic strategy in maize, where multiproduct terpene synthases and promiscuous P450s collaboratively generate a flexible and robust terpenoid defense network.

Zea mays

Enzymatic innovations in Angelica pubescens reveal dual coumarin biosynthetic pathways driving metabolic diversification.

Coumarins are structurally diverse phenylpropanoid derivatives with ecological and pharmacological significance, yet the biosynthetic logic underlying their diversification remains incompletely understood in non-model medicinal plants. Angelica pubescens (Apiaceae), widely used in traditional Chinese medicine, accumulates a rich repertoire of furanocoumarins and dihydrofuranocoumarins, making it an ideal system to investigate this metabolic complexity. Here, we combined chromosome-level genome assembly, transcriptome and metabolite profiling, phylogenetics, and heterologous expression assays to dissect coumarin biosynthesis in A. pubescens. We identified two functionally specialized O-methyltransferases, ApOMT1 and ApOMT2, which catalyze regioselective methylation of xanthotoxol and bergaptol to yield the furanocoumarins xanthotoxin and bergapten. We also characterized ApCYP736A121, a cytochrome P450 enzyme that converts osthenol to the dihydrofuranocoumarin columbianetin via a previously unknown mechanism. Gene expression and metabolite accumulation patterns across tissues and developmental stages revealed functional partitioning among pathway branches. Phylogenetic and syntenic analyses indicated that ApOMT1 and ApOMT2 arose through subfunctionalization following gene duplication, whereas ApCYP736A121 evolved via neofunctionalization from a distantly related CYP736 ancestor. Together, our findings uncover dual biosynthetic routes to structurally distinct coumarins in A. pubescens and provide insights into the evolutionary mechanisms contributing to metabolic innovation in Apiaceae. This work lays a foundation for future efforts to engineer coumarin pathways and understand their ecological functions in medicinal plants.

Coumarins

Genomic prospecting and biochemical characterization of a novel thermostable 3-quinuclidinone reductase from hot spring metagenomes for efficient biocatalysis.

This study presents the discovery and characterization of a novel thermophilic 3-quinuclidinone reductase (ScQR) identified through metagenomic mining of hot spring environments. ScQR, a member of the short-chain dehydrogenase/reductase (SDR) superfamily, was heterologously expressed in Escherichia coli, and its catalytic properties were systematically characterized. The enzyme demonstrates exceptional thermal stability, retaining 86% of its activity after 48 hours at 70°C. Furthermore, K+ and Mg²+ ions significantly enhanced ScQR's activity at specific concentrations. Structural analysis revealed that ScQR adopts a typical SDR fold with a conserved catalytic triad (S141-Y155-K159), and it is NAD(H) dependent. Enzyme assays indicated that ScQR is highly stereoselective for (R)-3-quinuclidinol, with no activity against its enantiomer, (S)-3-quinuclidinol. The enzyme exhibits optimal activity at pH 9 and 85°C, making it a promising candidate for industrial applications requiring high thermal stability. Molecular dynamics simulations further revealed that ScQR preserves global structural integrity up to 360 K, whereas higher temperatures induce destabilization, predominantly in the C-terminal region and residues 95-100. In addition, structure-guided computational design enabled by LigandMPNN and UniKP yielded three ScQR variants with improved substrate affinity and catalytic efficiency while maintaining the overall fold and function. This work underscores the power of metagenomics with structure-driven protein design in discovering novel enzymes with unique catalytic properties from extreme environments and establishes ScQR as a promising biocatalyst for biotechnological and pharmaceutical applications.IMPORTANCEThis study reports the discovery of ScQR, a novel thermophilic 3-quinuclidinone reductase identified via metagenomic mining. ScQR represents one of the most heat-resistant members of the SDR superfamily discovered to date, maintaining 86% activity after 48 hours at 70°C. These findings establish ScQR as a robust biocatalyst for high-temperature pharmaceutical applications and demonstrate a scalable workflow for optimizing enzymes from extreme environments, offering significant value to the fields of biocatalysis and protein engineering.

computational design

FGF13 is not secreted from mouse neurons.

FGF13, a noncanonical fibroblast growth factor (FGF) and member of the fibroblast growth factor homologous factor (FHF) subset, lacks a signal sequence and was previously reported to remain intracellular, where it regulates voltage-gated sodium channels (VGSCs) at least in part through direct interaction with the cytoplasmic C-terminus of VGSCs. Recent reports suggest FGF13 is secreted and regulates neuronal VGSCs through interactions with extracellular domains of integral plasma membrane proteins, yet supportive data are limited. Using rigorous positive and negative controls, we show that transfected FGF13 is not secreted from cultured cells in a heterologous expression system, nor is endogenous FGF13 secreted from cultured neurons. Furthermore, using multiple unbiased screens including proximity labeling proteomics, our results suggest FGF13 remains within membranes and is unavailable to interact directly with extracellular protein domains.

Animals

Archaea produce peptidoglycan hydrolases that kill bacteria.

The social life of archaea is poorly understood. In particular, even though competition and conflict are common themes in microbial communities, there is scant evidence documenting antagonistic interactions between archaea and their abundant prokaryotic brethren: bacteria. Do archaea specifically target bacteria for destruction? If so, what molecular weaponry do they use? Here, we present an approach to infer antagonistic interactions between archaea and bacteria from genome sequence. We show that a large and diverse set of archaea encode peptidoglycan hydrolases, enzymes that recognize and cleave a structure-peptidoglycan-that is a ubiquitous component of bacterial cell walls but absent from archaea. We predict the bacterial targets of archaeal peptidoglycan hydrolases using a structural homology approach and demonstrate that the predicted target bacteria tend to inhabit a similar niche to the archaeal producer, indicative of ecologically relevant interactions. Using a heterologous expression system, we demonstrate that two peptidoglycan hydrolases from the halophilic archaeaon Halogranum salarium B-1 kill the halophilic bacterium Halalkalibacterium halodurans, a predicted target, and do so in a manner consistent with peptidoglycan hydrolase activity. Our results suggest that, even though the tools and rules of engagement remain largely unknown, archaeal-bacterial conflicts are likely common, and we present a roadmap for the discovery of additional antagonistic interactions between these two domains of life. Our work has implications for understanding mixed microbial communities that include archaea and suggests that archaea might represent a large untapped reservoir of novel antibacterials.

N-Acetylmuramoyl-L-alanine Amidase

RNG2 tethers the conoid to the apical polar ring in Toxoplasma gondii to enable parasite motility and invasion.

The conoid is a dynamic, tubulin-based structure conserved across the Apicomplexa that undergoes extrusion during egress, gliding motility, and invasion in Toxoplasma gondii. This organelle traverses the apical polar ring (APR) in response to calcium waves and plays a critical role in controlling parasite motility. While the actomyosin-dependent extrusion of the conoid is beginning to be elucidated, the mechanism by which it remains apically anchored to the APR is still unclear. RNG2, a protein localized to both the conoid and the APR, has emerged as a strong candidate for mediating this connection. Biochemical analysis revealed that RNG2 is an unstable protein, undergoing extensive proteolytic cleavage both in the parasite and in heterologous expression systems. Its biochemical properties, with the presence of large coiled-coil domains, likely facilitate the formation of concatenated assemblies, enabling RNG2 to serve as a dynamic and resilient bridge between the conoid and the APR. Using a combination of iterative ultrastructure expansion microscopy and immunoelectron microscopy, we confirmed the localization of RNG2 to the 22 tethering elements bridging the APR and the conoid. Conditional depletion of RNG2 led to the striking detachment of the intact conoid organelle from the APR, supporting an essential role for RNG2 as a tether. Cryo-electron tomography of conoid-less parasites revealed that, in the absence of RNG2, the apical vesicle remains anchored to the plasma membrane, while the rhoptries follow the detached conoid. Although RNG2 depletion only mildly reduces microneme secretion, the parasites are immotile and exhibit impaired rhoptry discharge, highlighting the critical role of proper conoid anchorage in motility and host cell invasion. Comprehensive mutagenesis of RNG2 identified distinct regions responsible for binding to the conoid and the APR, and demonstrated that the full-length, intact protein is essential for bridging these two structures and for its functional activity. Altogether, RNG2 emerges as a pivotal protein that ensures conoid functionality and coordination in Coccidia.

Toxoplasma

Searching for new plastic-degrading enzymes from the plastisphere of alpine soils using a metagenomic mining approach.

Plastic materials, including microplastics, accumulate in all types of ecosystems, even in remote and cold environments such as the European Alps. This pollution poses a risk for the environment and humans and needs to be addressed. Using shotgun DNA metagenomics of soils collected in the eastern Swiss Alps at about 3,000 m a.s.l., we identified genes and their proteins that potentially can degrade plastics. We screened the metagenomes of the plastisphere and the bulk soil with a differential abundance analysis, conducted similarity-based screening with specific databases dedicated to putative plastic-degrading genes, and selected those genes with a high probability of signal peptides for extracellular export and a high confidence for functional domains. This procedure resulted in a final list of nine candidate genes. The lengths of the predicted proteins were between 425 and 845 amino acids, and the predicted genera producing these proteins belonged mainly to Caballeronia and Bradyrhizobium. We applied functional validation, using heterologous expression followed by enzymatic assays of the supernatant. Five of the nine proteins tested showed significantly increased activities when we used an esterase assay, and one of these five proteins from candidate genes, a hydrolase-type esterase, clearly had the highest activity, by more than double. We performed the fluorescence assays for plastic degradation of the plastic types BI-OPL and ecovio® only with proteins from the five candidate genes that were positively active in the esterase assay, but like the negative controls, these did not show any significantly increased activity. In contrast, the activity of the positive control, which contained a PLA-degrading gene insert known from the literature, was more than 20 times higher than that of the negative controls. These findings suggest that in silico screening followed by functional validation is suitable for finding new plastic-degrading enzymes. Although we only found one new esterase enzyme, our approach has the potential to be applied to any type of soil and to plastics in various ecosystems to search rapidly and efficiently for new plastic-degrading enzymes.

Humans

Multi-Omics and Integrative Analytics in Natural Products Discovery.

Natural products (NPs) have long been an essential source of new bioactive compounds for drug discovery; however, traditional methods for screening and isolating these compounds can be slow and often yield diminishing returns. Fortunately, advanced multi-omics and computational approaches present powerful solutions to these challenges. This review highlights innovative methodologies that integrate metabolomics, genomics, transcriptomics, and proteomics with bioinformatics and analytical chemistry to accelerate NP discovery. For instance, untargeted metabolomics platforms like high-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) and Global Natural Products Social (GNPS) molecular networking allow for comprehensive profiling of new compounds, while targeted isotope-labeling strategies enhance this process. Additionally, genome and metagenome mining tools such as antibiotics and secondary metabolite analysis shell (antiSMASH), Deep Biosynthetic Gene Cluster (DeepBGC), and Pipeline for Reconstructing Integrated Syntheses of Metabolites (PRISM) quickly identify biosynthetic gene clusters (BGCs) in both cultured and uncultured organisms, often using heterologous expression to validate products. Transcriptomic analyses, including RNA sequencing (RNA-seq), co-expression networks, and fluxomics, help clarify how pathways are regulated, while quantitative proteomics techniques like tandem mass tags/isobaric tags for relative and absolute quantitation (TMT/iTRAQ) and label-free methods, along with chemoproteomics approaches such as cellular thermal shift assay and thermal proteome profiling (TPP), uncover molecular targets and their mechanisms of action. This review also places significant emphasis on the role of artificial intelligence (AI) and machine learning (ML) in integrating multi-omics data, spanning activities from constructing gene-metabolite correlation networks to leveraging knowledge graphs and graph neural networks for data fusion and functional prediction. Finally, this review concludes by discussing the synergistic benefits of multi-omics for natural-product discovery, addressing current technical challenges, and exploring future directions toward high-throughput, intelligent data integration for next-generation NP research.

Biological Products