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Constructed wetland-microbial fuel cell (CW-MFC) is a promising technology for wastewater treatment with concurrent resource and energy recovery. However, its power generation capacity and mercury (Hg) removal efficiency are significantly limited by the insufficient electron transfer of anode materials. In this study, CW-MFCs were developed using zero-valent iron and siderite as anode materials. The incorporation of iron-based substrates significantly enhanced Hg removal, with total Hg removal efficiencies increasing by 22.9 % and 18.4 %, respectively, compared to conventional CW-MFCs. The integration of iron-based materials increased the availability of organic/inorganic electron donors by 9.1-350.0 %, thereby enhancing power generation performance by 17.9-34.9 %. This enhancement promoted the reduction of Hg(II) and inhibited the formation of methylmercury. Additionally, the electricity generated by the MFC facilitated Fe(III)/ Fe(II) redox cycling, which supported continuous corrosion and electron release from the iron anode. Metagenomic and electrochemical analyses demonstrated that the use of iron-based materials in CW-MFCs improved both extracellular and intracellular electron transfer efficiencies, and strengthened the synergistic interaction between the iron-based anode and electroactive bacteria. The genes that related to Hg(II) reduction, including merA, were also improved. Generally, this study highlights the potential of iron-based anodes to enhance Hg removal and power generation in CW-MFCs, providing a sustainable and energy-recovering strategy for wastewater treatment.

Biological methane (CH4) removal from dilute air streams (200-5,000 ppm) is fundamentally constrained by slow mass transfer, primarily due to CH4's low solubility and diffusivity in water. Conventional biofilters, the current state of technology, suffer from long start-up periods, progressive pore clogging, and high transport energy requirements. This study investigates a "dry" biofilm concept designed to overcome these bottlenecks by minimizing the aqueous boundary layer while maintaining microbial activity via capillary-mediated nutrient delivery. Using concentrated biomass of the methanotroph Methylomicrobium buryatense 5GB1C, three generations of membrane-supported reactor configurations were evaluated. The third-generation (G3) design utilized a cellulose-bead capillary support to maintain a physical gap between the membrane and the liquid surface, enabling continuous drainage of metabolic water. Experimental results demonstrated that the "dry" G3 configuration achieved CH4 removal rate of 148.9 mg·m-2·hr-1 at 4000 ppm, representing a 397% improvement over the first-generation floating mesh configuration. At 500 ppm, G3 design achieved a CH4 removal rate of 18.6 mg·m-2·hr-1, corresponding to an over six-fold improvement over one of the highest reported values. Furthermore, the system enabled immediate start-up post-inoculation and maintained an optimal microenvironment pH (8.8-9.0) even as the bulk medium acidified. These results establish that replacing liquid-phase diffusion with drastically faster gas-phase transport provides a high-efficiency framework for mitigating low-concentration CH4 emissions. With the added benefits of minimal pressure drop and easy biomass harvesting via scraping, this dry biofilm approach offers a scalable and sustainable alternative for atmospheric methane mitigation.

Natural attenuation is a nature-based approach that relies on intrinsic biogeochemical and microbial processes to mitigate mixed heavy metals and organic pollutants in aquifer, yet its efficiency is limited by electron donor scarcity and suppressed microbial activity. Here, a low-energy bioelectrochemical strategy that uses a mild electric field (0.6 V) was introduced to sustainably stimulate the attenuation of chromate [Cr(VI)] and dichloromethane (DCM) co-contamination in groundwater. With minimal electrical input, Cr(VI) and DCM removal reached 95.0 ± 2.6% and 95.2 ± 0.5%, substantially outperforming the no-voltage and single-pollutant systems. The electric field alleviated electron-donor limitations and metabolic inhibition, enabling efficient and energy-conserving bioremediation. Mineralogical and spectroscopic analyses (SEM-EDS, XPS, XRD) confirmed the reduction of Cr(VI) to Cr(III) precipitates (e.g., Cr2O3) and the progressive dechlorination and mineralization of DCM. Integrated metagenomic and metatranscriptomic profiling revealed active functional guilds (e.g., Sphingopyxis, Pseudomonas, Hyphomicrobium) expressing key genes for chromate reduction (yieF, chrA), dehalogenation (dhlA, dcmA), and electron-shuttling metabolism (ribE). This work demonstrates an applicable remediation technology that can be powered by renewable electricity and integrated into secure groundwater management systems. It offers a pathway for environmentally safe pollutant mitigation by harnessing nature-based microbial processes, supporting the transition toward enhanced natural attenuation.

Two endophytic actinobacteria of the genus Streptomyces-EKL1.1T and EKS8.28T-were isolated from the surface-sterilized leaf and twig of a red gum tree (Eucalyptus camaldulensis Dehn.) grown in highly saline soil, as reported in a previous study. These strains were aerobic and feature well-developed substrate mycelia and aerial mycelia with spiral spore chains. Strains EKL1.1T and EKS8.28T shared the highest 16S rRNA gene sequence similarity with Streptomyces mexicanus NRRL B-24196T (99.2%) and Streptomyces glomeratus LMG 19903T (99.0%), respectively. The comparative genome study of strain EKL1.1T and its closest type strain, S. mexicanus NRRL B-24196T, showed the highest dDDH, ANIb, and ANIm values of 31.8, 85.3, and 88.5%, respectively. The comparative genome study of strain EKS8.28T and its closest type strain, Streptomyces cynarae HUAS 13-4T, had the highest dDDH, ANIb, and ANIm values of 41.8, 89.6, and 91.4%, respectively. The genotypic and phenotypic properties of strains EKL1.1T and EKS8.28T distinguished these two strains from the closely related species with validly published names. The name proposed for the new species of strain EKL1.1T is Streptomyces kalasinensis (= NRRL B-65753T = TBRC 19936T). The name proposed for the novel species of strain EKS8.28T is Streptomyces phytorum (= NRRL B-65754T = TBRC 19937T). Strain EKL1.1T could only inhibit one fungus, Cladosporium sp. LB1, moderately (35%). Strain EKS8.28T could inhibit Fusarium sp. RE1 (71.1%), Curvularia sp. LB12 (62.2%), and Cladosporium sp. LB1 (50%). Strains EKL1.1T and EKS8.28T could produce indole acetic acid (IAA) and solubilize phosphate. The optimum spore inoculum of strains EKL1.1T and EKS8.28T to promote seedling growth parameters of eucalyptus was 107 and 108 spores/mL, respectively. Strains EKL1.1T and EKS8.28T facilitated the development of eucalyptus seedlings under saline conditions. They also enhanced the growth of eucalyptus seedlings in planta by augmenting shoot length and fresh weight. Genome mining of these strains reveals their in vitro and in planta characteristics, including biosynthetic gene clusters of bioactive compounds and several genes associated with plant growth enhancement under stressful conditions. They can be formulated as inoculants to improve eucalyptus plantations for sustainable agriculture in the future.

Persulfate-based advanced oxidation processes (PS-AOPs) coupled with anaerobic digestion (AD) present a novel strategy for efficient energy recovery and resource utilization of organic solid waste. In this integrated system, reactive oxygen species (ROS) play a critical role, yet the mechanism by which ROS from PS-AOPs pretreatment affects AD remains unclear. This review systematically assesses the roles of PS-AOPs in AD systems. ROS are produced through thermal, iron-based and carbonaceous activation. These ROS disrupt hydrophilic functional groups of lignocellulose and extracellular polymeric substances. Such reactions cause physical disintegration and chemical modification at the solid-liquid interface, thereby enhancing substrate bioavailability and solid-liquid separation. ROS-induced oxidative stress enriches stress-tolerant microbes, which generate small-molecule acids and facilitate methanogenesis. Small organics from ROS decomposition also stimulate anaerobic fermentative bacteria. Meanwhile, accumulated SO42- facilitates the proliferation of sulfate-reducing bacteria (SRB), reshaping metabolic functions. ROS oxidation yields small organic molecules. These compounds serve as electron donors and substrates. These organic molecules impose selective pressure to modulate system redox potential and enrich DIET-related microbes. Meanwhile, SRBs mediate sulfur cycling to lower hydrogen partial pressure and promote SCFAs conversion to HAc. The interaction accelerates interspecies electron transfer and methanogenesis. Additionally, ROS degrade emerging contaminants through ring-opening, deamination and hydroxylation reactions. Furthermore, functional degrading bacteria are enriched to construct a synergistic chemical-biological purification system. Finally, this review summarizes major existing challenges, such as microbial damage from excessive oxidation, imbalanced electron competition and toxic byproduct formation. The findings provide valuable references for practical application of PS-AOPs-assisted AD.

Photosynthetic biohybrid systems present a promising approach for coupling wastewater nitrogen removal with energy recovery. However, their application is restricted by photocatalyst instability, biocompatibility issues, and the separation of hydrogen production and denitrification processes. Here, a catalyst-free, light-driven co-culture system was developed by pairing the light-responsive electroactive bacterium Delftia acidovorans YP-3 with Klebsiella oxytoca DX-3, a strain that can produce hydrogen and reduce nitrate. In batch cultures, the YP-3/DX-3 co-culture generated 345.52 mL/L H2 within 48 h and enhanced the removal of nitrate, nitrite, and total nitrogen compared to the DX-3 monoculture. Electrochemical, extracellular polymeric substance, and metabolomic analyses indicated enhanced redox activity, decreased electron-transfer resistance, NADH-related metabolism, and potential interspecies electron transfer via direct contact and soluble redox-active mediators. In a synthetic swine wastewater-fed anaerobic sludge reactor, the co-culture accomplished 90.25 % nitrate removal, minimized nitrite accumulation, and enriched functional groups related to electron transfer, hydrogen production, and nitrogen removal. This system offers proof-of-concept evidence for integrating light-assisted hydrogen recovery with wastewater nitrogen removal.

High ammonium wastewater characterized by low C/N provides a suitable environment for the partial nitrification and anammox (PNA) process. As a typical representative, mature landfill leachate (MLL) also presents challenges due to refractory organic matter. However, compared to the floc sludge system, the robust biofilm system is limited by the prolonged construction due to the slow growth of autotrophic bacteria. Based on seeding AnAOB on heterotrophic biofilm cultured on virgin carriers, this study achieved rapid construction of the PNA process in an integrated fixed-film activated sludge (IFAS) system within 62 days. The nitrogen removal efficiency (NRE) stabilized at 95.5 ± 0.8% under diluted MLL environment. The heterotrophic biofilm characterized by polysaccharide-rich extracellular polymeric substances (EPS), provided loose and porous structure for AnAOB colonization. Candidatus Brocadia rapidly migrated from the floc sludge to the biofilm, reaching a relative abundance of 0.29% within 21 days, while becoming undetectable in the floc sludge at the same time. Subsequently, under diluted MLL environment, the increased EPS protein and eDNA induced a denser biofilm, establishing a broadened nitritation active zone that enhanced the NO2- supply and promoting the enrichment of AnAOB in the biofilm. Candidatus Brocadia enriched in the biofilm to a relative abundance of 5.18%. The floc sludge potentially degraded organic matter to mitigate inhibition and create suitable dissolved oxygen conditions for biofilm AnAOB, ensuring the stable operation of the system. Overall, this study provides a practical strategy for the rapid construction and stable operation of PNA in IFAS system.

Interspecies electron transfer (IET) determines the efficiency of electro-syntrophic metabolism in electroactive microbial communities. Compared with mediated IET (MIET) mediated by diffusible electron shuttles, contact-based direct IET (DIET) can enable more efficient energy transfer. However, engineering DIET is constrained by the challenges of maintaining stable and conductive cell-to-cell interfaces. In this study, we developed a conductive and adhesive interface by in-situ polydopamine (PDA) nano-encapsulation of Shewanella oneidensis MR-1 (SW, electron donating partner) surfaces. The coating promoted stable and intimate coaggregation of SW with Rhodopseudomonas palustris (RP, electron accepting partner). This cell-to-cell PDA interface promoted a shift in the dominant IET mode from H2-mediated MIET toward contact-dependent electron transfer involving outer membrane C-type cytochromes. Notably, nitrogenase-derived CH4, used as a quantitative indicator of IET efficiency, increased by ∼380 % in the engineered two-species community. This study provided a simple and promising approach for IET manipulation, which may open new avenue for microbial community engineering of electro-syntrophic systems.

Two endophytic bacterial strains, designated as Sx8-8ᵀ and SI8-4ᵀ, were isolated from the stem and leaf tissues, respectively, of Kaempferia marginata Carey collected in Thailand. A comprehensive taxonomic investigation employing a polyphasic approach was conducted to characterize these strains. Strain Sx8-8ᵀ is a Gram-negative, aerobic, rod-shaped, non-spore-forming bacterium that produces yellow pigment on Reasoner's 2A agar (R2A) medium. Phylogenetic analysis based on 16S rRNA gene sequences placed this strain within the genus Sphingobium, showing the highest similarity (98.5%) to Sphingobium chungbukense KACC 12347ᵀ (=DJ77T). The draft genome was 4.7 Mb in size with a G+C content of 64 mol%. Genome-wide comparisons with closely related type strains yielded an average nucleotide identity based on blastn (ANIb) and MUMmer (ANIm) values of 82.2-84.0% and 86.7-86.9%, respectively, with digital DNA-DNA hybridization (dDDH) values of 28.4-29.1%. Chemotaxonomic data supported its affiliation to the genus, with Q-10 identified as the major respiratory quinone, along with characteristic fatty acid and polar lipid profiles. These findings support the proposal of a novel species, Sphingobium trunci sp. nov., with Sx8-8ᵀ (=LMG 33805ᵀ=TBRC 17746ᵀ) as the type strain. Strain SI8-4ᵀ is a Gram-positive, aerobic, spore-forming, rod-shaped bacterium, producing pale pink pigment on R2A medium. It was identified as a member of the genus Peribacillus, sharing the highest 16S rRNA gene sequence similarity (99.0%) with Peribacillus frigoritolerans JCM 11681ᵀ and Peribacillus muralis DSM 16288ᵀ. The genome was 4.6 Mb in size, with a G+C content of 43 mol%. Comparative genomic analyses revealed ANIb and ANIm values of 80.0-86.0% and 84.3-87.8%, respectively, while dDDH values were 24.3-32.1%. The major quinone was MK-7, and the fatty acid and polar lipid compositions were consistent with members of the genus Peribacillus. Based on genotypic and phenotypic distinctiveness, strain SI8-4ᵀ is proposed to represent a novel species, Peribacillus folii sp. nov. The type strain is SI8-4ᵀ (=KACC 23903ᵀ=KCTC 43756ᵀ=TBRC 17747ᵀ).

Nitrogen loss during composting can be substantial; however, it can be reduced by applying new insights to better control the substrate C/N ratio and optimise overall composting performance. This study provides mechanistic insights into how substrate C/N governs nitrogen loss during kitchen waste composting. By combining nitrogen speciation analysis, qPCR, and metagenomics analyses, this study explored the potential biochemical mechanisms of nitrogen loss. The results showed that a high substrate C/N ratio significantly reduced nitrogen loss by approximately 37 % (C/N of 25) and 47 % (C/N of 30) compared to the baseline C/N of 20. A higher substrate C/N ratio enhanced nitrogen fixation and assimilation processes while suppressing ammonification and denitrification related potential. The relative abundance of key ammonification-related genera (e.g. Thermobifida and Leuconostoc) and denitrification-related genera (e.g. Pseudomonas and Geobacillus) were decreased at a high substrate C/N ratio, resulting in synergistic mitigation of NH3 and N2O emissions. A small reduction in germination index was observed at substrate C/N ratio of 30 compared with 25. Overall, the results suggest the need to optimize substrate C/N ratio for nitrogen conservation while maintaining overall composting performance.

The industrial production of fatty acids by Schizochytrium sp. is constrained by low fatty acid content. While chemical regulation represents a promising non-genetic strategy to enhance lipid synthesis, its application is limited by the inefficient optimization of multi-additive combinations due to vast experimental spaces and complex interactions. To address this, the study developed a machine learning driven experimental design platform utilizing Batch Bayesian Optimization to efficiently navigate this high-dimensional parameter space. From an initial set of 13 candidates, four key additives were selected. Over six iterative rounds of optimization, the model's success rate for recommending effective combinations increased from 0.00 % to 77.50 %. Validation experiments confirmed 100.00 % reproducibility. This approach generated seven optimized regimens, including binary, ternary, and quaternary combinations, which enhanced the total fatty acids (TFA) content by approximately 50.00 %, achieving a final TFA content exceeding 50.00 % of dry cell weight in shake-flask cultures without significant growth inhibition, which represents the highest TFA content reported for Schizochytrium sp. under shake-flask conditions. This work establishes the power of machine learning driven optimization to unlock the synergistic potential of chemical additives, providing an efficient and scalable strategy for the sustainable microbial production of nutritionally valuable lipids.

Soil salinization limits global agriculture, threatening food security and impairing crop productivity on irrigated lands worldwide. Using hydroponic lettuce (Lactuca sativa L.) to exclude soil confounders, this study investigated the mechanism of FA-mediated salt tolerance in lettuce under NaCl stress. It further examined FA-induced lignin remodeling across NaCl salinity of 7 mS cm-1 with FA concentrations ranging from 0, 50, 100, 150, 200&#x202f;mg L-1. Transcriptomics, antioxidant profiling, and advanced structural analyses (2D-HSQC NMR, GPC, GC-MS, etc.) were combined to elucidate the interplay among lignin modification, redox homeostasis, and photosynthetic protection. The treatment cleaved &#x3b2;-O-4 linkages, oxidised S/G units, and reassembled them into 400-700&#x202f;Da FA-lignin hetero-conjugates. Concurrently, FA decreased ROS accumulation, stabilized chloroplast ultrastructure, increased thylakoid density and plastoglobuli, and, compared with salt-stressed controls, improved photosynthetic electron transport efficiency by 11&#x202f;%, biomass by 27&#x202f;%, and soluble sugars 3.9-fold (p&#x202f;<&#x202f;0.01). Transcriptomic analysis revealed that FA modulated the expression of genes associated with lignin synthesis, redox balance, and photosynthesis. FA significantly upregulated genes like CCT7 and CSLA9, enhancing cell cycle progression, cell wall synthesis, and photosynthetic efficiency, providing molecular evidence for FA-mediated physiological improvements. Excessive FA (200&#x202f;mg L-1) exerted inhibitory effects, confirming 150&#x202f;mg L-1 as the optimal dose. Based on these findings, we propose a "lignin remodelling-redox homeostasis-photosynthetic protection" model, wherein FA-mediated lignin modification reinforces xylem development and leaf cell wall stability, thereby enhancing salt tolerance and providing a precise dosage basis for saline vegetable production.

Using feed additives and their residues leads to the accumulation of heavy metals and antibiotics in the feces of fattening sheep, thereby posing a threat to the surrounding soil and ecological cycle. Chlorella, a novel feed raw material or additive widely applied in aquaculture, has the potential to mitigate such ecological risks. In this study, we investigated the potential of Chlorella pyrenoidosa as a dietary supplement for fattening lambs to mitigate multi-pollutant emissions from manure via gastrointestinal microbiome modulation. The results demonstrated that dietary supplementation with 3% Chlorella pyrenoidosa (W3) markedly reduced fecal concentrations of several heavy metals (Fe, Cu, Zn, Cr, As, Pb) and total phosphorus, while shifting phosphorus speciation toward more stable forms. Metagenomic analysis revealed that W3 reshaped the metabolic functional profile of the gastrointestinal microbiota and drove the succession of key microbial taxa, particularly promoting the proliferation of Clostridium and other genera in feces. Furthermore, Chlorella pyrenoidosa reduced the abundance of high-risk antibiotic resistance genes (ARGs, e.g., macB). It simplified the ARG-metal resistance gene co-occurrence network and was associated with an attenuated potential for vertical transmission of resistance genes along the digestive tract. Structural equation modeling further confirmed that pollutant reduction was closely associated with the functional remodeling of the microbiome. Thus, this study suggests that Chlorella pyrenoidosa may mitigate the environmental risks associated with heavy metals, bioavailable phosphorus, and ARGs in manure by regulating the gastrointestinal microbial ecosystem. This provides a novel strategy and theoretical basis for reducing source pollution in animal husbandry.

Food waste anaerobic membrane bioreactor (AnMBR) permeate contains high ammonium and residual organics, posing challenges to stable autotrophic nitrogen removal. A two-stage partial nitritation-anammox (PN/A) system was applied to investigate unit-specific robustness and adaptive recovery mechanisms during wastewater transition. Under permeate stress, the PN reactor rapidly stabilized, maintaining nitrite accumulation above 95.0% and ammonium removal around 55.0%, supported by sustained ammonia oxidation and nitrite oxidation suppression. In contrast, the anammox (AMX) reactor exhibited reversible deterioration, with total nitrogen removal efficiency (TNRE) decreasing to 55.8%, inhibited anammox activity, and NH4+-N/NO2--N accumulation. The sustained dominance of Candidatus Kuenenia indicated that the performance decline was primarily due to metabolic inhibition of retained anammox bacteria (AnAOB) rather than population washout, resulting in a temporary imbalance between nitrite supply and consumption. Following adaptive regulation through controlled loading, TNRE recovered above 90.0% at nitrogen loading rates near 1.0&#x202f;kg&#x202f;N&#x202f;m-3&#x202f;d-1. This recovery was accompanied by restoration of anammox activity, microbial restructuring, metabolic rebalancing, and granule reinforcement, which collectively re-established functional coupling and enabled long-term stable PN/A operation under full-strength AnMBR permeate.

Bio-crude oil obtained from hydrothermal liquefaction of biomass, comprising aqueous and organic fractions contains several value-added chemicals. In this study, hydrothermal liquefaction of palm empty fruit bunch fibers was conducted at different temperatures (225 - 275&#x202f;&#xb0;C) and water to biomass ratios (10:1 to 20:1) to find their effect on the concentration of organic acids in aqueous phase. The models developed fit the experimental responses well. Recycling of the aqueous phase was found to increase the concentration of organic acids significantly. One of the main component of aqueous phase was glycolic acid, which is worth extracting in its pure form to improve the sustainability of the process. This study adopted a methodological framework which develop a separation scheme integrated with solvent design using Computer-Aided Molecular Design (CAMD) to economically extract and recover glycolic acid. Solvent design for extraction involved a novel CAMD approach, which include the integration of Hansen Solubility Parameters (HSP), solvent power, selectivity and solvent loss. Further purification methods were then evaluated for purification of glycolic acid. An optimisation model was developed to identify the optimal solvent ratio, that directly impacts the economic viability of the process by minimising the solvent cost, glycolic acid and solvent losses via fixing the solvent added. The results suggested that the developed design strategy can efficiently and economically extract pure glycolic acid from the aqueous phase of bio-crude oil produced via hydrothermal liquefaction, where isobutene glycol is selected as the most efficient solvent for the extraction.

Light quality critically regulates pigment remodeling and carbon allocation in Haematococcus pluvialis, yet stage-resolved, single-cell quantification of these processes remains limited. Bulk pigment assays, confocal Raman spectroscopy, Raman chemical imaging, and 13C-based Raman stable isotope probing (Raman-SIP) were integrated to characterize pigment dynamics and de novo carbon incorporation across cultivation time and division stages under white, red, and blue light. A spectral correction was established to reduce carotenoid interference in the chlorophyll-related region, enabling clearer separation of pigment pools and improved agreement with bulk measurements. Blue light selectively promoted carotenoid accumulation, increased single-cell heterogeneity, and induced stage-dependent spatial reorganization, whereas red light preferentially enhanced chlorophyll-related signals. Raman-SIP revealed progressive 13C incorporation into pigment-associated molecular structures under all light treatments. Blue light produced the highest labeling fraction for the carotenoid-associated 1156/1137&#xa0;cm-1 pair on Day 7 (52&#xa0;%), whereas red light showed the highest corrected labeling fraction for the chlorophyll-related 1521/1490&#xa0;cm-1 pair (51&#xa0;%). Raman imaging further revealed pronounced intracellular heterogeneity and hotspot-like carotenoid distributions under blue light, with transmission electron microscopy providing ultrastructural context. This integrated, stage-resolved single-cell framework directly links light-quality regulation to pigment remodeling and carbon allocation dynamics in H. pluvialis.

Microalgae are promising photosynthetic platforms for high-value compounds, yet their industrial use is often hindered by a trade-off between robust growth and the metabolic burden of payload production or cell wall disruption. Constitutive engineering for these traits compromises cultivator fitness. Here we report the development of a versatile, thermal-regulated "PLUG-IN" chassis in Nannochloropsis oceanica that enables programmable control of metabolic output and cell integrity. Comparative transcriptomics identify two highly heat-inducible promoters (PNoED and PNoUK), which we use to construct a modular thermal gene-amplification. Heat-activated AtWRI1 expression enhances triacylglycerol and eicosapentaenoic acid accumulation, while temperature-dependent silencing of the cellulose synthase gene CesA1 triggers rapid cell-wall weakening without affecting growth under permissive conditions. Coupling metabolic and cell-wall modules yields strains capable of grind-free lipid recovery and substantially improved intracellular product accessibility. Notably, these engineered thermally controlled programs remain functional in mammalian hosts, demonstrating cross-kingdom compatibility. This work establishes a "plug-in" chassis compatible with mammalian systems that synchronizes growth, production, and cell-wall re-configuration, providing a versatile platform for photosynthetic bioproduction and microalgal synthetic biology.

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Pyrite-based bioretention systems hold substantial promise for the simultaneous removal of nitrogen and phosphorus from stormwater runoff. However, their performance under high-frequency and high-intensity rainfall conditions is often limited by the low electron-supply capacity of pyrite. To address this limitation, a mixed carbon source strategy was developed to enhance nutrient removal under complex rainfall conditions. Four bioretention systems, including the mixed carbon source-pyrite system (WCP), woodchip-pyrite system, corncob-pyrite system, and pyrite-only system, were constructed and systematically evaluated under simulated rainfall events with varying intensities and frequencies. Among all systems, WCP consistently achieved the best performance, with removal efficiencies of 88.1&#xa0;&#xb1;&#xa0;1.3% for ammonium, 86.6&#xa0;&#xb1;&#xa0;1.9% for nitrate, 87.0&#xa0;&#xb1;&#xa0;2.0% for total dissolved nitrogen, and 83.3&#xa0;&#xb1;&#xa0;4.3% for total dissolved phosphorus. Mechanistic analyses revealed that readily biodegradable carbon released from corncob promoted rapid heterotrophic denitrification during rainfall events, whereas recalcitrant carbon released from woodchips sustained pyrite-driven autotrophic denitrification during drying periods. Their complementary carbon-release characteristics synergistically enhanced nitrogen and phosphorus removal. In addition, mixed carbon sources reshaped the microbial community, enhanced cooperation between autotrophic and heterotrophic functional groups, and improved nitrogen transformation and electron transfer efficiency. Media characterization further showed that mixed carbon sources promoted FeS/FeS2 cycling, thereby facilitating pyrite regeneration and supporting long-term operational stability. Overall, this study elucidates a multi-dimensional enhancement mechanism driven by mixed carbon sources-complementary carbon release, microbial restructuring, and pyrite regeneration-and provides a robust and sustainable strategy for nutrient control in stormwater bioretention systems under complex rainfall conditions.