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Energies • 2026

Peer-to-peer (P2P) energy-trading has emerged as a promising mechanism for decentralized electricity markets, but its practical deployment is often limited by the difficulty of accounting for physical network constraints and transmission losses in real time. This paper presents a decentralized P2P energy trading mechanism that incorporates network constraints and transmission losses directly into the market-clearing process. The framework combines Power Transfer Distribution Factors (PTDFs) for pre-trade feasibility validation with an Enhanced Least Squares Method (ELSM) for loss estimation, enabling loss-aware settlement without computationally intensive and redundant AC power flow calculations. The mechanism is implemented on Hyperledger Fabric using Attribute-Based Access Control, Access Control Lists and Private Data Collections to ensure privacy and auditability. Numerical studies on a 3-bus and the IEEE 39-bus system show that the proposed approach closely reproduces AC Optimal Power Flow dispatch and cost outcomes, while significantly improving simplified DC-based loss models. The results demonstrate that physically feasible and economically efficient decentralized trading can be achieved in a permissioned blockchain environment.

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bioRxiv (Cold Spring Harbor Laboratory) • 2026

Angelman syndrome is a neurodevelopmental disorder caused by loss of the maternally inherited UBE3A allele and is characterized by severe cognitive, motor, and communication impairments. Increased delta (1-4 Hz) activity on electroencephalogram (EEG) assessed by visual inspection and by spectral power analysis is a robust feature of the disorder in humans and rodent models and is used as a biomarker of Angelman syndrome. This aspect of the phenotype has not been evaluated in the recently developed pig model of Angelman syndrome. Here, we analyzed scalp EEG recordings from freely moving pigs carrying a maternal UBE3A deletion ( UBE3A -/+ ) across three age groups to determine whether they recapitulate the delta power abnormalities characteristic of the disorder. UBE3A -/+ pigs exhibited elevated delta power during both wakefulness and sleep compared with wild-type littermates, with the largest differences observed during the awake state. The typical increase in delta power that accompanies the transition from wakefulness to sleep was also reduced in UBE3A -/+ pigs. These effects were observed across study groups, demonstrating that the maternal UBE3A -deletion pig model reproduces the elevated delta power EEG phenotype of Angelman syndrome. Our results establish noninvasive scalp EEG as a translationally relevant tool for assessing neural dysfunction in this large-animal model and provide a framework for preclinical therapeutic testing. This work strengthens the utility of the pig model for mechanistic studies and therapeutic development in Angelman syndrome.

Chemosphere • 2025

This study investigates the comparative effects of different nitrogen sources-peptone, tryptone, and bovine serum albumin (BSA)-on the growth, electron transport mechanisms, and MFCs performance of halophilic bacteria Bacillus clausii J1G-o%B. The objective is to identify the most effective nitrogen source for optimizing bacterial growth and enhancing MFC efficiency. Comprehensive analysis reveals that tryptone and peptone significantly enhance bacterial growth and stability compared to BSA. Increased concentrations of these nitrogen sources correlate with elevated ammonia production and notable pH changes, indicating heightened metabolic activity. The non-linear relationship between scan rate and current density suggests diffusion-limited redox reactions. Notably, higher tryptone concentrations significantly increase the electron transfer rate constant to 3.66 ± 0.02 s -1 when the concentration increases to 0.1 g/100 mL. Early voltage increases at around the 30th hour to 0.175 V under the T-0.1 condition further support the critical role of tryptone in accelerating bacterial growth and biofilm formation. Cyclic voltammetry experiments demonstrate that nitrogen source type and concentration influence electrical double layer characteristics. These findings underscore the potential of tryptone to optimize Bacillus clausii electrochemical performance, achieving a maximum power density of 36.93 mW/m 2 at a current density of 196 mA/m 2 , paving the way for bioelectrochemical system applications.

Journal of environmental management • 2025

Electroactive microorganisms are a promising approach for treating high-salinity organic wastewater, however, they are highly susceptible to salt stress, which can compromise their metabolic activity. In this paper, biochar supported nano-cerium dioxide catalyst (BC-CeO 2 ) was prepared to strengthen electroactive microorganisms in high salt environment. It was found that BC-CeO 2 significantly improved the bioelectrochemical and metabolic activity of microorganisms in high salt environment (600 mM NaCl) compared with the Control. At the initial stage of the reaction, the maximum power density of microbial fuel cells (MFCs) reached 343.21 mW/m 2 , and the degradation efficiency of norfloxacin (NOR) was 64.8 %, which was 1.7 times that of the Control. The analysis of microbial antioxidant properties demonstrated that BC-CeO 2 could significantly increase the activities of superoxide dismutase (SOD) and catalase (CAT), effectively enhancing the ability of microorganisms to scavenge reactive oxygen species produced by salt stress. Metagenomic analysis revealed that the abundance of KEGG pathways conducive to microbial growth and metabolism under BC-CeO 2 was relatively high, such as biosynthesis of amino acids (ko01230), microbial metabolism in diverse environments (ko01120) and so on. The enrichment of salt tolerant genes further illustrated the strengthening effect of BC-CeO 2 on microbial adaptation to high salt environment, including genes related to NADH ubiquinone oxidoreductase, Na + /H + antiporter, intracellular small molecule compatible substance synthesis and transport related enzyme system and K + transporter related genes. Furthermore, the activity changes of Na + /K + -ATPase, which regulates cell permeability, in different environments also confirmed this point. This paper provides an effective strategy for enhancing the treatment of high-salt organic wastewater by electroactive microorganisms.

Journal of environmental management • 2025

Capacitive anodes hold promise for enhancing microbial fuel cells (MFCs) in wastewater treatment, yet the impact of capacitive anodes with different capacitance type and mass specific capacitance on the performance remains unclear. This study compared electric double layer (EDL) and pseudo-capacitance anodes, evaluating their power generation and pollutant removal in MFCs. Results showed that EDL anode with 2 mg mass loading achieved 5.48-fold higher specific capacitance (27.95 ± 7.39 F/g) than pseudo-capacitance anodes (5.10 ± 1.48 F/g), enabling a higher maximum power density (P max ) of 561.09 ± 109.54 mW/m 2 . Increasing EDL mass loading further amplified capacitive current contributions (39 %), P max and stored charge. Although there was no obvious effect on sulfamethoxazole (SMX) (a persistent organic pollutant) removal, COD removal was improved in MFCs with capacitive anodes. EDL anode with 6 mg mass loading had satisfactory comprehensive performance of power generation and COD removal (>80 %). Based on Pearson correlation analysis and microbial co-occurrence networks, the mechanism of capacitive anodes to enhance MFCs power generation by increasing capacitive current, electrochemically active bacteria (EAB) abundance, and adenosine triphosphate (ATP) content and dehydrogenase activity (DHA) was revealed. These findings demonstrate that enhancing the anode intrinsic capacitance, particularly EDL capacitance, can significantly improve MFCs performance. This study will not only provide a new direction for the electrode design of MFCs, but also advance the development of MFCs as dual-functional devices integrating power generation and energy storage capabilities in wastewater treatment.

International microbiology : the official journal of the Spanish Society for Microbiology • 2025

In this work, the isolation and identification of pigment-producing fungi from substrate samples collected in the Sonoran Desert, Mexico, are described. Three fungal isolates, named CR2, SM1, and GBS, were selected for their ability to produce colored pigments. The redox properties of these pigments were characterized using UV-Vis spectroscopy and cyclic voltammetry. The GBS pigment, produced by the fungus Forliomyces uniseptata, exhibited the best electrochemical behavior, with a reversible redox cycle, indicating its potential as a redox mediator (RM) for microbial fuel cells (MFCs). The effect of different light wavelengths on the growth kinetics of F. uniseptata and pigment production was evaluated. Blue light moderately accelerated pigment biosynthesis, while darkness promoted fungal growth. Finally, the GBS pigment was tested as a RM in a MFC inoculated with Bacillus subtilis. A maximum power density of 37 μW/cm 2 . It is suggested that mass transfer could limit performance.

Biosensors & bioelectronics • 2025

Microbial fuel cells (MFCs) were recognized as sustainable technologies for wastewater treatment and energy production, yet their low power output and high cost hindered practical applications. In this study, a novel MOF-on-LDH nanocomposite (CuZr-MOF@NiFe-MLDH) was synthesized via a two-step hydrothermal method and co-precipitation to enhance the activity and stability of MFC cathodes. Cation vacancies in the modified LDH,denoted as NiFe-MLDH were generated by alkaline of NiFe-LDH, which improved structural stability and conductivity while facilitating CuZr-MOF doping. A hierarchical pore system and synergistic interactions among metal ions were revealed by material characterizations. Electrochemical tests demonstrated an 80 mV positive shift in the onset potential, the limiting current density was increased by a factor of 1.65. A maximum power density of 283.02 mW/m 2 was achieved by CuZr-MOF@NiFe-MLDH as an MFC cathode catalyst, which was 3.76 times higher than that of NiFe-LDH (75.27 mW/m 2 ). The MOF-on-LDH architecture optimized mass transport and electron transfer through micro-mesoporous synergy, offering a new strategy for designing high-performance MFC catalysts.

3 Biotech • 2025

Climate change and water pollution are now critical global challenges due to their significant impact on environmental sustainability. Bioelectrochemical systems have emerged as an alternative to address these issues, treating wastewater while generating electricity in a sustainable and environmentally friendly manner. However, scale-up and commercialization have been limited by several factors, including high cost, long start-up times, and insufficient power generation. In recent years, the manipulation of the quorum sensing system has gained attention as a potential solution to improve power generation and reduce start-up times. Quorum sensing is a type of bacterial cell-to-cell communication in which bacteria produce and release chemical molecules or autoinducers to regulate their gene expression in response to cell population density, thereby controlling various microbial features. In this review, we summarize the efforts that have been made to improve the performance of different bioelectrochemical systems by manipulating the quorum sensing circuit of the microorganisms that drive these systems and we critically examine the different mechanisms by which quorum sensing could affect bioelectrochemical system's performance. Focusing on quorum sensing type 1, the most common quorum sensing circuit in Gram-negative bacteria, we categorize the different laboratory-scale approaches that have been used to understand these strategies, their gaps, and future research needs.

Journal of environmental management • 2025

This research investigated a novel 60 L baffled-hybrid constructed wetland-microbial fuel cell (CW-MFC) integrating metallurgical coke (Metcoke) and coagulation sludge as bed materials to optimize pollutant removal and bioelectricity recovery. Among four bed material arrangements, the hybrid matrix of Metcoke and coagulant sludge achieved superior chemical oxygen demand (COD) reduction of 94.35 ± 5.16 %, total phosphorus removal of 92.43 ± 2.51 %, and total nitrogen removal of 82.20 ± 5.40 %. The system demonstrated robust bioelectricity production with a maximum power density of 24.97 mW/m 3 , facilitated by improved microbial adhesion and electron transfer processes. Furthermore, adaptability trials with sulfamethoxazole-contaminated hospital wastewater and methylene blue dye effluent exhibited removal efficiencies of 79.65 ± 5.09 % and near-complete degradation, respectively, confirming the reactor's efficacy across complex wastewater matrices. This integrated CW-MFC configuration provides an economical and sustainable approach for decentralised wastewater treatment coupled with concurrent energy recovery, particularly suited for resource-limited settings.

Bioprocess and biosystems engineering • 2025

The bioremediation of penoxsulam, a commonly encountered aquatic herbicide, was investigated using a single-chamber air microbial fuel cell (MFC) system. This study focused on how the modulation of electron transfer through exogenous electron shuttles (riboflavin (RF), anthraquinone-2-sulfonate (AQS)) and respiratory inhibitors (rotenone, capsaicin) affects electrogenesis and the degradation of penoxsulam. The addition of electron shuttles significantly improved both MFC power generation and pollutant removal efficiency in a dose-dependent manner, with optimal concentrations identified for maximum performance. In contrast, respiratory inhibitors strongly suppressed both processes, leading to an increase in charge transfer resistance. This study links macroscopic changes in performance with intracellular bioenergetic parameters, showing that electron shuttles maintain higher intracellular NAD + levels and current densities, likely by promoting NAD + regeneration, whereas inhibitors deplete NAD + availability and hinder electron flow. Additionally, an analysis of key respiratory enzymes indicated that Cytochrome C oxidase plays an important role in facilitating extracellular electron transfer to the anode. Inhibitor studies provide further support for the importance of Complex I and downstream cytochrome pathways for power generation and degradation. By establishing the relationships between mechanisms and performance and proposing an integrated electron transfer model, this research highlights important enzymatic and metabolic control points for optimizing MFC-based bioremediation. These findings provide important insights into enhancing bioelectrochemical systems for concurrent environmental remediation and sustainable energy recovery.

Bioprocess and biosystems engineering • 2025

The development of innovative bioprocessing technologies has resulted from the growing global need for sustainable forms of energy and environmentally friendly waste treatment. In this review, we focus on the combined electro-fermentation and microbial fuel cells, as they form a hybrid system that simultaneously addresses wastewater treatment, bioenergy production, and bioplastics. Even though microbial fuel cells produce electricity out of the organic waste by the use of electroactive microorganisms, electro-fermentation improves the microbial pathways through the external electrochemical management. The novelty of the review is that it compares the two technologies in detail and identifies the synergistic potential of the technologies as well as assesses the efficiencies of their operations, scalability, and impact on the environment. The research utilizing Scopus and PubMed directories was done by means of a systematic literature review that included 147 peer-reviewed experimentation and technology-oriented studies published during the period of 2012-2024. The main results lead to the conclusion that integrated systems imply significant increase in power densities (up to 2000 mW/m 2 ), the enhancement of electron transfer efficiency (increased by 30-40%), large-scale production of useful products such as methane, hydrogen and organic acids. In spite of this promise, there are still difficulties regarding microbial stability, material costs, and energy balance. The review identifies the existing gaps and future opportunities, which include the development of novel electrode materials, the employment of better reactor designs and designer microbial consortia. The combination of such systems may become an interesting strategy of the next generation of biorefineries and have a good prospect to become a part of the circular economy and climate as a whole.

Bioresource technology • 2025

A lab-scale single-chamber microbial fuel cell (SCMFC) with a heterotrophic nitrifying-aerobic denitrifying bacteria (HNADB)-functionalized biocathode was developed to treat high-salinity ammonium-rich wastewater for the first time. Results showed that the system achieved a total nitrogen removal efficiency and rate of 92.5 % and 2.2 mg/(L∙h), respectively, far superior to autotrophic nitrifying bacteria (ANB) biocathode and platinum carbon cathode systems. The maximum power density of the HNADB-biocathode system was 1.4 times that of the ANB-biocathode system. The HNADB-biocathode SCMFC maintained stable performance throughout 350 days of operation. Microbial community analysis confirmed that electrical stimulation further enriched salt-tolerant electroactive HNADB in the HNADB-functionalized biocathode biofilm, particularly the genus Vitellibacter. This facilitated the coupling of nitrogen removal and electricity generation. Microbial metabolism and electron transfer activity tests indicated that the bidirectional incentive between extracellular electron transfer (EET) and intracellular electron transfer (IET) in the HNADB-functionalized biocathode biofilm may be the key factor driving enhanced nitrogen removal and electricity generation. Additionally, redox mediators (mainly flavin and cytochrome c) and electrode biofilm pseudocapacitance may play crucial roles in EET. This study provides a potentially effective strategy for improving the high-salinity ammonium-rich wastewater treatment.

Biosensors & bioelectronics • 2025

Understanding the mechanisms of extracellular electron transport (EET) in biofilms is critical for advancing bioelectrochemical systems (BES). In this study, four bacterial strains - Pseudarthrobacter scleromae, Arthrobacter halodurans, Brevundimonas vesicularis and Rhodococcus fascians - were isolated from activated sludge and shown to form electroactive biofilms (EAB) on graphite-paste electrodes, including those modified with single-walled carbon nanotubes (SWCNTs). Microscopy and spectroscopy confirmed biofilm formation and matrix structure, as well as biofilm viability under SWCNTs cultivation conditions. High-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) identified pyocyanin and 2-hydroxyphenazine as endogenous redox mediators. Electrochemical analyses revealed that SWCNTs significantly enhanced redox conductivity and reduced charge transfer resistance by integrating into the polysaccharide matrix and facilitating direct electron flow from phenazines to the electrode. The resulting biofilm-based biosensors exhibited 5-min BOD 5 detection with lower limits down to 0.12 mg O 2 /dm 3 . Microbial fuel cells using these systems generated power densities up to 6 mW/m 2 . The ability of aerobic microorganisms to form functional EAB and independently generate effective redox mediators presents a promising approach for creating sustainable, affordable, and scalable BES. Additionally, this research fosters the advancement of next-generation biosensors and eco-friendly energy devices by combining biological activity with nanomaterial-enhanced interfaces.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

This study presents a significant advancement in a capacitive carbon felt/carbon nanotube/polythiophene (CF/CNT/PTh) bioanode. The CF framework provides mechanical stability. CNTs form a mesoporous structure (Barrett-Joyner-Halenda (BJH) pore volume: 0.016991 cm 3 /g), which supports increased populations of electroactive microorganisms. High-throughput sequencing confirmed a 6.67-fold increase in the relative abundance of electroactive genera. The key innovation of the CF/CNT/PTh is the incorporation of PTh to redesign the bioelectrochemical interface. The hydrophobic surface of PTh (confirmed by Fourier-transform infrared spectroscopy and Brunauer-Emmett-Teller analysis) reduces interfacial water barriers. Consequently, the charge-transfer resistance decreases by 65.3 % (R ct  = 2.80 Ω), as measured via electrochemical impedance spectroscopy. Additionally, the pseudocapacitive properties of PTh enable the storage of 5842.55C/m 2 of charge and generate a stronger bioelectric field (-578 mV open-circuit potential (OCP)), which enhances microbial activity. These effects create an "energy hub" in the bioanode, as stored and real-time electrons merge during discharge. Therefore, the CF/CNT/PTh bioanode achieves a current density of 147.925 A/m 2 and a power density of 1216.03 mW/m 2 , which is 1.64 times that of bare CF. This design establishes a novel system through a microbial habitat environment constructed with CNT and a polythiophene-enhanced electron transfer mechanism, offering an innovative solution for micropower applications.

Bioresource technology • 2026

This study developed a microbial fuel cell (MFC) integrated with magnetic biochar (Fe 3 O 4 @BCFPs) and the biosurfactant-producing strain Klebsiella sp. HN02 (HN02) to realize synergistic degradation of hydrophobic para-xylene (PX) and power generation. Using 5 g/L Fe 3 O 4 @BCFPs, the system achieved rapid PX removal and enhanced power density by 1.94-fold to 0.53 ± 0.01 W/m 3 . The Fe 3 O 4 @BCFPs also promoted electron transfer and stimulated biosurfactant secretion from HN02, improving the bioavailability of hydrophobic PX. This synergy enhanced dehydrogenase activity, maintained 83.0 % live cells in biofilms, and increased the emulsification index by 83.3 %, thereby establishing a highly active bioelectrochemical interface. Key intermediates (4-methylbenzyl alcohol and p-toluic acid) revealed a PX degradation pathway involving side-chain oxidation and benzene ring cleavage, accompanied by reduced toxicity. This study demonstrates a scalable strategy for treating industrial volatile organic compounds with simultaneous electricity generation by coupling the adsorption and capture of PX with efficient electroactive biodegradation.

Biodegradation • 2025

This study investigates the novel application of biochar derived from Bixa orellana fruit shell (BOFS), an underutilized agricultural waste, to enhance the performance of microbial fuel cells (MFCs) for textile dye wastewater treatment and energy generation. Four different BOFS biochar doses (0.5, 1, 1.5, and 2 g) were examined, and the optimal dose of 1.5 g achieved a maximum power density of 300 mW/m 2 -representing a 24-fold enhancement over the control-along with 88.39% COD removal, 81.6% decolorization efficiency, and 84.4% TDS reduction. Structural and compositional analyses using SEM, EDX, FTIR, and UV-Vis spectrophotometry confirmed improved biofilm formation, efficient pollutant adsorption, and azo bond degradation, indicating synergistic enhancement of both bioelectrochemical and treatment performance. The study uniquely demonstrates the dual functionality of BOFS biochar as a low-cost, conductive, and sustainable additive that promotes microbial adhesion and electron transfer while valorizing agricultural waste. These findings position BOFS biochar as an innovative, eco-friendly bioelectrochemical enhancer for scalable applications in wastewater remediation and renewable energy generation.

Journal of agricultural and food chemistry • 2025

This study investigated how manganese mineral addition enhanced the extracellular electron transfer (EET) capacity of humic acids (HAs) in soil bioelectrochemical systems. Through electrochemical analysis, EEM-PARAFAC, hetero-2DCoS, and structural equation modeling, two complementary transformation pathways of HA components were identified. The first was a microbial-driven aromatic condensation that converted intermediate Component 2 into aromatic-rich, electron-accepting Component 3. The second was an abiotic Mn 4+ -mediated oxidative fragmentation that produced low-molecular-weight, electron-donating Component 1. These dual processes increased the redox heterogeneity of the HA matrix and supported bidirectional electron shuttling, facilitating continuous redox cycling for pollutant degradation, which enhanced system performance, resulting in a 23% higher phenanthrene removal efficiency and nearly 2-fold greater power density. The findings established a mechanistic basis for the synergistic microbial and abiotic regulation of humic substances, offering new insights for sustainable soil remediation.

Bioresource technology • 2026

Azithromycin (AZ), a broad-spectrum antibiotic, is commonly found in aquatic habitats. This study investigated two microalgae-microbial fuel cell (m-MFC) configurations, A-AZ-MFC (AZ in the anode) and C-AZ-MFC (AZ in the cathode), which were run in fed-batch mode under open- and closed-circuit conditions (10-200 mg/L AZ). AZ removal increased from 43 % in an open circuit to 83 % when the circuit was closed in A-AZ-MFC and from 68 % to 84 % in C-AZ-MFC. While both A-AZ-MFC and C-AZ-MFC achieved comparable AZ degradation (83-84 %), A-AZ-MFC demonstrated superior electrochemical output (Power density: 275 mW/m 3 ; Net energy recovery: 0.11 kWh/kg COD; Coulombic efficiency: 26 %) and higher microbial tolerance (IC 50  = 77.02 mg/L), indicating effective electron transfer and steady biofilm activity. Both designs achieved successful detoxification, as evidenced by comparable transformation product profiles and lower effluent toxicity. These findings demonstrate m-MFCs, especially anode-optimized systems, as sustainable platforms for the removal of antibiotics and the production of bioenergy.

RSC advances • 2026

The development of high-performance anode materials remains a critical challenge in advancing microbial fuel cells (MFCs). In this work, we present a novel strategy employing ternary transition metal Co-Fe-Ni sulfides to overcome the inherent trade-off between catalytic activity and structural stability commonly observed in conventional polymetallic sulfides. Through a facile one-pot solvothermal approach, we synthesized low-crystallinity CoFeNiS x (Co-Fe-Ni) ternary sulfides with precisely tunable Co/Fe/Ni molar ratios. When integrated as an MFC anode, the optimized Co-Fe-Ni sulfide delivered a maximum power density of 3915 mW m -2 using Escherichia coli ( E. coli ) as the biocatalyst, representing an 8.4% enhancement over its binary CoFeS x (Co-Fe) analogue. This performance exceeds that of most previously reported carbon-based anodes. The synthesized transition metal sulfides combine ease of fabrication with outstanding electrocatalytic efficiency. Our findings highlight the underexplored potential of ternary transition metal sulfides in engineering next-generation bioelectrochemical interfaces.

Bioelectrochemistry (Amsterdam, Netherlands) • 2025

Bloodstream bacterial infections, a major health concern due to rising sepsis rates, require prompt, cost-effective diagnostics. Conventional methods, like CO 2 -based transduction, face challenges such as volatile metabolites, delayed gas-phase signaling, and the need for additional instruments, whereas electrochemical sensors provide rapid, sensitive, and efficient real-time detection. In this study, we developed a bioreceptor-free Prussian blue (PB) sensor platform for real-time bacterial growth monitoring in blood culture. PB thin films were electrodeposited onto a screen-printed carbon electrode (SPCE) via cyclic voltammetry (CV) technique under optimal conditions. The electrochemical performance of PB/SPCE was assessed using differential pulse voltammetry (DPV) against exoelectrogenic bacteria, including E. coli, P. aeruginosa, S. aureus, and E. faecalis. The proposed sensor exhibited surface-controlled electrochemical kinetics and bacteria-driven metal reduction from PB to Prussian white (PW), facilitated by extracellular electron transfer (EET). It showed significant sensitivity with an extensive detection range of 10 2 -10 8 CFU/mL for E. coli and S. aureus, and 10 3 -10 8 CFU/mL for P. aeruginosa and E. faecalis, with reliable detection limits. The sensor accessed the viability of the pathogen within 3 hrs, offering a rapid, efficient alternative to traditional, labor-intensive methods for blood-based diagnostics.

Bioresource technology • 2025

Bioavailable organic-rich food waste (FW) is a promising feedstock for renewable hydrogen production. However, its highly suspended and complex nature presents substantial challenges for producing high-purity hydrogen in dual-chamber microbial electrolysis cells (MECs). This study examined the effects of pretreating FW through pre-fermentation and/or filtration on its microbial electrolysis. Both methods enhanced the exoelectrogenic utilization of FW, with pre-fermentation being especially effective by conditioning substrate composition, while filtration alone was less advantageous due to associated energy loss. The MECs fed with pre-fermented FW exhibited significantly higher performances, achieving the highest hydrogen yield of 1,029 mL/g chemical oxygen demand fed (39.1 % increase over raw FW) when pre-fermentation was followed by filtration. Bioanodes across all MECs were dominated by exoelectrogenic bacteria, mainly Geobacter and Desulfovibrio, with significantly greater abundance observed with pre-fermentation. These findings highlight the value of pretreatment, particularly pre-fermentation, and warrant further optimization research to maximize FW conversion into hydrogen.

Bioresource technology • 2025

Efficient interfacial energy conversion and rapid charge transfer are crucial for application-oriented microbial electrochemical systems (MES) and depend on affordable high-performance anodes. Herein, hierarchically porous 3D anodes with controlled millimeter-scale macropores (1-2 mm) were fabricated via carbonization of phenolic foam embedded with expanded polystyrene (EPS) sacrificial templates. Optimizing EPS loading (4 wt%) and pore-sizes yielded anode L-4M, exhibiting appropriate hydrophilicity (contact angle: 60.0 ± 0.7°) and enhanced electrochemically active surface area (ECSA: 61 cm 2 ) attributed to surface oxygen-containing groups and multiscale porosity. The L-4M achieved a remarkable maximum power density of 3800 ± 80 mW m -2 , 2.1-fold higher than carbon-cloth anodes. Engineered macropores facilitated unprecedented microbial colonization depth (≥ 2.5 mm) and biomass density (1300 ± 36 μg cm -2 ) predominated by Geobacter sp. (75 % relative abundance). This millimeter-scale pore engineering strategy enhanced bio-accessible surface area, substrate diffusion, and electroactive biofilm development, offering a scalable approach for high-current-density MES.

Enzyme and microbial technology • 2025

This study was conducted to delineate microbial community development and composition on both working and counter electrodes in single-chamber microbial electrolysis cells (MECs) using synthetic wastewater. Two separate bioelectrochemical reactors were inoculated with anaerobic sludge. The first was operated at an anodic potential poised at + 0.4 V and the second one at a cathodic potential poised at -0.7 V, both vs. an Ag/AgCl reference electrode. The performance of the MECs, including current generation, bioelectrochemical activity of the biofilms on both the working and counter electrodes, and chemical oxygen demand (COD) depletion were monitored over the last 45 days of operation. Scanning electron microscopy (SEM) and 16S rRNA gene sequencing were performed to delineate the development and morphology of the microbial communities on both the working and the counter electrodes. The current generated at the anodic working electrode provided evidence of the growth of anode-respiring exoelectrogens (Clostridium sensu stricto). Similarly, the Faradaic current data at the cathodic working electrode confirmed the formation of an electroactive biofilm dominated by acetoclastic and hydrogenotrophic methanogens (Methanothrix and Methanobacterium). Microbial communities on the counter electrodes were found to be richer but less diverse compared to those on the working electrodes. These communities were likely influenced by the fluctuating potentials at the counter electrodes. SEM observations were consistent with the microbial analysis. These findings demonstrate the ability of a mixed inoculum to shift towards anode-reducing and cathode methanogenic communities using a complex substrate on a constant working electrode and varying counter electrode potentials.

Advanced science (Weinheim, Baden-Wurttemberg, Germany) • 2025

Electroactive biofilms (EABs) are essential components of both natural and artificial bio-electrochemical systems (BESs). However, the inevitable decay of EABs during prolonged operation can diminish their performance. In this contribution, an effective and noninvasive strategy for rejuvenating aging biofilms by the elastic deformation of anode material is approved. The synthesized wood tracheid-like structures anode material showed excellent compressibility and fatigue resistance in a wet state. The findings indicate that after the elastic deformation of the anode, aged biofilm exhibited a 37.5% increase in metabolic activity, and multi-SIM images confirmed the removal of dead cells. Analysis of the extruded substance revealed a significant removal of loosely bound extracellular polymeric substance which doesn't contribute directly to electron transfer. Community analysis demonstrated the rejuvenation process suppressed the ecological competition from non-exoelectrogens. Overall, there is a notable 25.97% increase in power density following the elastic deformation of the anode. Additionally, ion diffusion, specific capacitance, and catalytic response current all improved. To the knowledge, this is the first report employing an anode deformation strategy to restore decayed mix-cultured electroactive biofilm, which is vital for the practical long-term application of BESs. This work also offers new insights into the mechanical influence of anode materials on microorganisms.

Scientific reports • 2025

Anaerobic digestion (AD) is an effective method to treat swine manure and recover energy. However, swine manure with high total solid concentration often leads to long startup time of anaerobic digesters, low degradation efficiency of organic matter and incomplete fermentation. Herein, the hydrothermal hydrolysates of digestate obtained at two centrifugal speeds (i.e., the supernatant derived from 4000 to 10,000 rpm, respectively, named H4000 and H1000) co-digested with swine manure were conducted to investigate the effects of hydrolysate addition on AD startup and performance. Although the concentrations of organics were a slightly higher in H4000 than in H10000, a rapider biogas production occurred in the co-digestion of the H10000 hydrolysate and swine manure, indicating that the finer hydrochar was more optimal to prompt AD startup and performance than larger hydrochar. The fine hydrochar in the hydrolysate had a higher charge storage capability, and lower electron-transfer resistance, which could enhance the direct interspecies electron transfer between bacteria and methanogens and microbial activity. Also, hydrolysate addition could promote the growth of potential exoelectrogenic bacteria in AD. These findings provide a deep understanding of the effects of hydrolysate on the AD systems and are helpful for developing AD techniques for swine manure treatment.

Nature communications • 2025

Living biophotovoltaics represent a potentially green and sustainable method to generate bio-electricity by harnessing photosynthetic microorganisms. However, barriers to electron transfer across the abiotic/biotic interface hinder solar-to-electricity conversion efficiencies. Herein, we report on a facile method to improve interfacial electron transfer by combining the photosynthetic cyanobacterium Synechococcus elongatus PCC 7942 (S. elongatus) with a conjugated polyelectrolyte (CPE) atop indium tin oxide (ITO) charge-collecting electrodes. By self-assembly of the CPE with S. elongatus, soft and semitransparent S. elongatus/CPE biocomposites are formed with three-dimensional (3D) conductive networks that exhibit mixed ionic-electronic conduction. This specific architecture enhances both the natural and mediated exoelectrogenic pathway from cells to electrodes, enabling improved photocurrent output compared to bacteria alone. Electrochemical studies confirm the improved electron transfer at the biotic-abiotic interface through the CPE. Furthermore, microscopic photocurrent mapping of the biocomposites down to the single-cell level reveals a ~ 0.2 nanoampere output per cell, which translates to a 10-fold improvement relative to that of bare S. elongatus, corroborating efficient electron transport from S. elongatus to the electrode. This synergistic combination of biotic and abiotic materials underpins the improved performance of biophotovoltaic devices, offering broader insights into the electron transfer mechanisms relevant to photosynthesis and bioelectronic systems.

Microbial biotechnology • 2025

Shewanella oneidensis, recognised as an important model organism for exoelectrogenic electron transport, has been extensively studied for its potential applications in bioelectrochemical systems. To date, the activity of transposable elements in this organism has not been conclusively investigated. This study focused on transposases, specifically insertion sequences (IS), which make up approximately 4.7% of the organism's genome, and evaluated their impact on genome stability under stress conditions. Using whole genome sequencing, two IS families, ISSOD1 and ISSOD2, were identified as the most active, both showing similar transposition patterns across all tested stressors. A CRISPR/dCas9 cytosine deaminase system was used to introduce stop codons in the ISSOD2 transposase genes, resulting in a significant reduction of transposition events under stress conditions. Analysis of transposition patterns revealed a high frequency of insertions occurring on the megaplasmid, which predominantly carries non-essential genes. Experiments performed here to delete the megaplasmid resulted in the elimination of approximately 35% of its sequence, including an unexpected complete loss of the ori/repA region. Therefore, it was hypothesised that the megaplasmid either exists in a metastable state, possibly representing a cointegrated intermediate within the ISSOD9 (Tn3 member) transposition mechanism, or consists of two replicons that have been combined in previous assemblies due to long overlapping homologies resulting from the presence of ISSOD9. These findings highlight the dynamics of transposable elements in S. oneidensis and suggest strategies to improve strain stability by inactivating these elements and at least reducing megaplasmid sequences. Such approaches could improve the suitability of the organism for industrial applications.

iScience • 2025

Exoelectrogenic biofilms is crucial for the energy generation and wastewater treatment by bioelectrochemical systems. In this study, two kinds of saline-alkali tolerant mixed exoelectrogenic cultures were enriched from biogas slurry. These mixed exoelectrogens produced current densities of 1,034 ± 30 and 974 ± 53 μA·cm -2 , which were 1.68 and 1.58 times higher than G. sulfurreducens PCA at pH 9.0, respectively. Under alkaline conditions with the addition of 1.5% NaCl, the maximum current densities for BS-N 2 (546.66 ± 139.20 μA·cm -2 ) and BS-O 2 (583 ± 22.91 μA·cm -2 ) were about 2.45 and 2.61 times higher than G. sulfurreducens PCA, respectively. The BS-O 2 exhibited a high power density of 1,109 ± 115 mW·m -2 at pH 9.2 in a microbial fuel cell. The community analysis revealed Proteobacteria as the predominant phylum, with Firmicutes and Bacteroidetes as the dominant families within the biofilms. These findings provide valuable insights for further research on exoelectrogenesis in challenging environments.

Journal of applied microbiology • 2025

Paraclostridium sp. AKS46 was shown to have high exoelectrogenic activity. The current study investigated whether membrane vesicles (MVs) contribute to electrogenic activity of this organism.

Bioresource technology • 2026

This study investigated the effects of Fe-Mn MOF-derived carbon composite (Fe-Mn MDC) on anaerobic digestion (AD) performance of food waste (FW) and elucidated the underlying mechanisms. The methane yield increased to 457.44 ± 14.21 mL/g VS under 0.05 g/g TS Fe-Mn MDC addition, representing a 36.47 % increase compared to the control group. Metagenomics analysis indicated that Fe-Mn MDC altered the microbial community structure, enriched the abundance and mutualism of exoelectrogenic bacteria (Geobacter) and electroactive methanogenic microorganisms (Methanothrix) involved in direct interspecies electron transfer. The metabolic activity of hydrogenotrophic methanogens was enhanced under Fe-Mn MDC addition, and the content of dehydrogenase and coenzyme F420 was also stimulated, thereby accelerating substrate consumption and methane production. The physicochemical characterization results of Fe-Mn MDC demonstrated that it could act as an electron shuttle and facilitate proton transfer. Besides, AD system exhibited not only an increase in e-pili and c-type genes abundance, but also an enhanced representation of gene modules linked to the biosynthesis of V/A-type ATPases (M00159) and F-type (M00157), which further indicated that Fe-Mn MDC enhanced the proton-coupled electron transfer in AD system. These results provided potential applications in FW management and new insights into the mechanism of renewable energy recovery from AD.

3 Biotech • 2025

Petroleum refinery wastewater (PRWW) with 4% salinity was subjected to treatment and simultaneous generation of energy in air cathode-microbial fuel cell (MFC). Substrate load (SL) such as 0.41 gCOD/L, 0.84 gCOD/L, 1.26 gCOD/L, 1.78 gCOD/L and 2.25 gCOD/L was trialed in air cathode MFC. COD (chemical oxygen demand) reduction was 88% (total COD) and 87% (soluble COD) at optimized SL of 1.78 gCOD/L. Corresponding power and current density derived at optimized SL of 1.78 gCOD/L was 879 mW/m 2 and 1052 mA/m 2 respectively. Degradation of low and high molecular weight petroleum hydrocarbons in the PRWW was greater than 90% to 100%  and 71% to 82% respectively. Supplementation with a mild nutritional substrate in PRWW accelerated the hydrocarbon biodegradation with time reduction in MFC operated at 1.78 gCOD/L SL. Phylogenetic analysis revealed the dominancy of exo-electrogenic halophilic strains such as Ochrobactrum , Marinobacter , Bacillus and Stenotrophomonas in the reactor. Thus the bioaugmentation of halophiles in MFC efficiently treated PRWW and harvested bioenergy under saline condition.

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Scientific Reports • 2025

The pathogenic profiles of seven Shewanella spp. positive cases identified during diarrhea surveillance in Beijing, China, in 2023 were characterised. Sentinel hospitals collected patient information and stool samples, while regional centres for disease control (CDC) performed cultures and real time PCR. Whole-genome sequencing (WGS), average nucleotide identity (ANI) analysis, phylogenetic analysis, virulence gene and resistance gene analysis of the Shewanella spp. isolates were conducted, as well as phenotypic resistance analysis. The detection rate in the stool samples collected from 354 diarrhea patients was 1.98% (7/354). The time of disease onset of six out of the seven patients ranged from July 17–22, 2023. The incubation period ranged from 8 to 12 h with 3–50 episodes/day. Three subjects reported having consumed potentially contaminated seafood. The seven isolated strains of Shewanella spp. (named as S1-S7) were closely related to S. algae, belonged to the algae clade, and were all novel ST (sequence typing) strains. A total of 125,738 SNPs (single nucleotide polymorphism) were identified in the core genomes of the seven Shewanella strains. Twenty-six virulence-related genes in five categories were identified, with chemotaxis and flagella-related genes being the most abundant (26.92%, 7/26), followed by secretion system- and serum resistance-related genes at 23.08% (6/26) and 15.38% (4/26), respectively. Shewanella spp. were detected in patients with diarrhea at a certain level. Seafood should be the key food category for monitoring and seafood markets should become a key monitoring site for Shewanella spp. The novel STs of the algae clade isolated from diarrhea patients in this study may potentially help in tracking circulating strains. Further in-depth investigations are required to precisely elucidate the correlation between Shewanella infections and human diarrhea and the pathogenic characteristics of this infection.

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Bioelectrochemistry • 2025

Unconventional natural gas pipeline corrosion is associated with microbes, especially sulfate-reducing bacteria (SRB), though it is uncertain if SRB's role is overemphasized. Using metagenomics, corrosion immersion, and microbial cultivation, diverse hydrocarbon-degrading microorganisms, such as Shewanella, in corroded pipeline rust layers, oil-water mixtures, and produced water from unconventional natural gas fields are identified. These bacteria use crude oil as a carbon source, accelerating pitting corrosion of carbon steel and forming corrosion product films (Pitmax = 28.96 μm). The 16S rRNA sequencing results show that Shewanella, prevalent in various steel service environments, is a potential key microorganism in pipeline corrosion. X70 steel exhibits lower electron transfer resistance than Desulfovibrio in the Shewanella medium. Shewanella's aerobic respiration degrades crude oil and oxidizes iron, speeding up iron oxide formation and magnesium phosphate precipitation. Microbial acidification of the oil-water medium also contributes to severe pitting corrosion beneath the oil film. Crude oil accelerates microbial growth. Thus, studying carbon steel corrosion in oil-water environments must consider the impact of hydrocarbon-degrading microorganisms.

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ACS Nano • 2025

The toxicity of negatively charged nanoplastics (NNP) to bacteria is generally subtler than that of positively charged counterparts, owing to limited NNP-cell interaction. This study hypothesized that common environmental cations (Na+, Mg2+, Ca2+) could enhance interaction between NNP and Shewanella oneidensis, thereby inducing biological effects. Settling experiments and dynamic light scattering analyses showed that NNP-cell interaction increased in the order of Ca2+ ≈ Mg2+ > Na+, which can be attributed to the decreased electrostatic repulsion, as confirmed by extended Derjaguin-Landau-Verwey-Overbeek theory calculations. Although coexposure to NNP and cations did not result in significant lethality, extracellular electron transfer (EET) to insoluble electron acceptors was significantly inhibited by coexposing to NNP and Ca2+ (NNP+Ca2+, by 37%) or Mg2+ (NNP+Mg2+, by 20%), but not by NNP alone or NNP and Na+ treatments. Two-dimensional correlation spectroscopy indicated that membrane proteins predominantly mediate bacterial interactions with NNP. Physical membrane damage and structural alterations of membrane proteins were observed following coexposure to NNP+Ca2+ and NNP+Mg2+, impairing the direct EET pathways. Transcriptomic and physiological analyses further revealed that NNP+Ca2+ upregulated persister marker genes (spoT, ppx, relA) and induced ATP depletion, triggering cellular dormancy and suppressing membrane protein-mediated processes. By contrast, NNP+Mg2+ exposure activated protective responses, including two-component systems and flagellar assembly, consistent with the milder impairment of EET. Notably, these effects were absent in treatments with either cations alone or NNP alone. These findings reveal an overlooked ecological impact of NNP and underscore the potential for distinct bacterial responses to NNP in varying aquatic environments.

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Antimicrobial Agents and Chemotherapy • 2025

ABSTRACT Tigecycline is a last resort antibiotic that is used to treat serious infections; however, some bacteria have developed tigecycline resistance by producing a tigecycline-inactivating enzyme or tigecycline resistance efflux pump, encoded by tet(X) and tmexCD-toprJ genes, respectively. Tons of seafood are consumed annually in China; however, whether seafood harbors tigecycline-resistant bacteria is not known. In this study, we isolated various tigecycline-resistant bacteria from retail seafood; among these, Shewanella was the predominant tigecycline-resistant genus (33/76, 43.4%). Genomic sequencing revealed that two Shewanella strains carried the tet(X4) gene, while one Shewanella chilikensis strain co-harbored tmexCD2-toprJ2 and blaNDM-1 genes. The tet(X4) and tmexCD2-toprJ2 were found to be located on novel members of the SXT/R391 family of integrated conjugative elements (ICEs). As per our knowledge, this is the first report on the emergence of SXT/R391 ICEs carrying tet(X4) or tmexCD2-toprJ2 gene in Shewanella strains. The SXT/R391 family ICEs could mediate the spread of tigecycline resistance genes among aquatic bacteria, and contact between seafood and consumers may lead to the dissemination of tigecycline-resistant bacteria. Our study revealed that Shewanella spp. may act as potential reservoirs of tigecycline resistance genes.

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Microbial Genomics • 2025

Graphical Abstract Comparative genomic analysis revealed that I-F3 CASTs serve as important mobile genetic elements mediating horizontal transfer of functional genes associated with defence, resistance and electron transfer in Shewanella. The transposition function of a new I-F3 CAST variant carried by strain ANA-3 was assessed both endogenously and heterologously.

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Journal of Microbiology and Biotechnology • 2025

Vanadium dioxide (VO2) nanoparticles have various application potentials such as smart windows and electronic devices due to their unique phase transition properties. However, conventional VO2 synthesis methods require harsh conditions and toxic reducing agents, leading to environmental problems. In this study, we developed an eco-friendly method to biosynthesize VO2 nanoparticles using Shewanella sp. strain HN-41 under anaerobic conditions at 30°C and neutral pH. Morphological observations revealed that biogenic VO2 nanoparticles with an average size of 4.3 nm were in the form of granules presented inside and outside the cells. These nanoparticles were identified as VO2 by differential scanning calorimetry (DSC) analysis, which showed a phase transition temperature of 61.9°C, consistent with that of VO2. Furthermore, we observed an active formation of vesicles containing VO2 nanoparticles by the cross-sectioned transmission electron microscopy (TEM) analysis. Thus, in addition to the direct extracellular formation of VO2 nanoparticles through anaerobic respiration, bacterial membrane vesicles likely play a role in expelling nanoparticles from the cell, potentially mitigating their toxicity. These findings highlight metal reducing bacteria could be a biological green agent for the production of valuable VO2 nanoparticles under anaerobic environmental conditions.

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Protein Science • 2025

The Gram‐negative Shewanellaceae family is well known for its ability to transfer catabolically derived electrons to extracellular terminal electron acceptors through electron conduits that permeate the outer membrane. The primary conduit is MtrCAB, a trimeric porin‐cytochrome complex that contains the cell surface exposed decaheme cytochrome MtrC. This donates electrons to extracellular substrates, including OmcA, soluble metals, organic electron shuttles, and insoluble metal oxides. However, it is not clear whether this broad substrate specificity requires specific sites for binding and reduction, or whether reduction occurs through non‐specific interactions near exposed hemes on the cytochrome surface. Shewanella oneidensis MtrC is composed of four domains, with the hemes closely packed and distributed evenly between domains II and IV. The domains are arranged to allow electron transport across the cytochrome via interdomain electron transfer, but the significance of this conserved feature is not understood. Here we use site‐directed mutagenesis to generate an MtrC variant that is comprised only of domains I and II (MtrCDI,II). The properties of this MtrCDI,II are effectively identical to domains I and II of full‐length MtrC. Whole‐cell assays revealed that S. oneidensis cells replacing full‐length MtrC with MtrCDI,II had significantly lower rates of OmcA, flavin mononucleotide, and Fe(III) citrate reduction. Our results demonstrate that MtrC domains III and IV contain sites for association of specific substrates, enabling the reduction of extracellular electron acceptors in S. oneidensis.

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eLife • 2025

Lysogens, bacteria with one or more viruses (prophages) integrated into their genomes, are abundant in the gut of animals. Prophages often influence bacterial traits; however, the influence of prophages on the gut microbiota–host immune axis in animals remains poorly understood. Here, we investigate the influence of the prophage SfPat on Shewanella fidelis 3313, a persistent member of the gut microbiome of the model marine tunicate, Ciona robusta. Establishment of a SfPat deletion mutant (ΔSfPat) reveals the influence of this prophage on bacterial physiology in vitro and during colonization of the Ciona gut. In vitro, deletion of SfPat reduces S. fidelis 3313 motility and swimming while increasing biofilm formation. To understand the in vivo impact of these prophage-induced changes in bacterial traits, we exposed metamorphic stage 4 Ciona juveniles to wildtype (WT) and ΔSfPat strains. During colonization, ΔSfPat localizes to overlapping and distinct areas of the gut compared to the WT strain. We examined the differential expression of various regulators of cyclic-di-GMP, a secondary signaling molecule that mediates biofilm formation and motility. The pdeB gene, which encodes a bacterial phosphodiesterase known to influence biofilm formation and motility by degrading cyclic-di-GMP, is upregulated in the WT strain but not in ΔSfPat when examined in vivo. Expression of the Ciona gut immune effector, VCBP-C, is enhanced during colonization by ΔSfPat compared to the WT strain; however, VCBP-C binding to the WT strain does not promote the excision of SfPat in an SOS-dependent pathway. Instead, VCBP-C binding significantly reduces the expression of a phage major capsid protein. Our findings suggest that SfPat influences host perception of this important colonizing commensal and highlights the significance of investigating tripartite dynamics between prophages, bacteria, and their animal hosts to better understand the gut microbiota-host immune axis.

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Journal of the American Chemical Society • 2025

The electrical conductivity of biofilms plays a critical role in advancing bioelectronics for energy and environmental applications, yet the underlying mechanisms remain poorly understood. Previous studies proposed interheme electron transfer between hemes 5 and 10 in the outer-membrane deca-heme cytochrome (OMC) MtrC as the rate-limiting step in the biofilm electron conduction of Shewanella oneidensis MR-1. However, the strong interheme electron coupling in MtrC suggests that interprotein interactions may represent the primary barrier to biofilm electron conduction. Here, we investigated the biofilm electron conduction mechanism with a focus on interprotein electron transfer in S. oneidensis MR-1. Conductive currents and their temperature dependence were measured for estimating the thermal activation energy (E a) by using indium tin-doped oxide (ITO) interdigitated electrodes in wild-type and mutant biofilms. While deletion of periplasmic cytochromes had a negligible impact on E a, the deletion of OmcA or MtrC increased E a 3-fold, revealing that interprotein interactions, particularly between OmcA and MtrC, dominate biofilm electron transfer over clonal OMC interactions. Furthermore, suppressing outer-membrane fluidity dramatically increased E a, while interheme exciton coupling negligibly changed in the OMCs, confirming the critical role of protein diffusion and collision on the outer membrane. Flavin binding to OmcA or MtrC reduced conduction currents attributable to heme centers but enhanced those assignable to noncovalently bound flavins, suggesting that flavin occupancy blocks hemes 2 and 7, which serve as key interprotein electron transfer sites. These findings provide a mechanistic foundation for engineering highly conductive biofilms through targeted protein interface optimization, offering new avenues for the development of bioelectronic technologies.