The technology is based on a stretchable organic electrochemical transistor, or OECT, a class of device that controls electrical current through the movement of ions. Unlike conventional silicon transistors, which primarily rely on electrons moving through rigid semiconductor channels, OECTs use an electrolyte to modulate the conductivity of an organic material. This ionic operation makes them particularly attractive for bioelectronics because they can interact with the chemical and electrical signals found in living tissue. The new device was designed to be both mechanically compliant and functionally adaptable.

In the study, led by Assistant Professor Hyunseok Shim, the researchers modified the conducting polymer PEDOT:PSS with two additives. These chemical adjustments improved the material’s electrical conductivity while also helping it withstand repeated stretching. The result was a transistor capable of maintaining its electronic performance even as it was deformed, an essential property for devices attached to skin, embedded in soft robotics, or integrated with moving organs. Conventional electronic components often lose efficiency or fail when subjected to continuous bending and stretching, but the modified polymer was engineered to reduce that vulnerability.

The most unusual feature of the transistor is that its function can be changed without replacing the device or redesigning the surrounding circuit. The researchers achieved this by varying the concentration of sodium chloride in the electrolyte surrounding the transistor. At higher salt concentrations, ions move in a way that enables fast and clearly defined switching between ON and OFF states. This behavior allows the device to operate as a digital logic element, carrying out basic computational operations. In practical terms, several such transistors could be connected to process sensor signals directly on a wearable patch.

At lower salt concentrations, however, the same transistor exhibits a slower, continuous response rather than a simple binary switch. Its electrical conductance changes gradually and retains a memory of previous stimulation, producing behavior comparable to an artificial synapse. Biological synapses adjust the strength of connections between neurons based on patterns of activity, and this type of analog response is central to neuromorphic computing. By reproducing a similar form of conductance modulation, the transistor could help wearable systems recognize changing biological patterns without sending every piece of raw data to an external processor.

The device also provides a visual indication of its internal operating state. As the transistor changes modes, the conducting polymer shifts in color from light blue to dark blue. This electrochromic behavior means that the device’s condition can be read by sight, without requiring a separate diagnostic circuit or wireless connection. A visible color change could be valuable in medical settings, where caregivers or users may need to determine quickly whether a soft electronic system is active, storing information, or operating in a different computational mode.

To demonstrate the concept, the researchers incorporated the technology into a wearable patch designed to monitor inflammatory edema and skin temperature. The patch was linked to a compression band that could tighten or loosen in response to changes detected by the sensors. Such a system could potentially help regulate pressure around swollen tissue, reducing the risk of excessive compression and associated tissue damage. Although the demonstration represents an early proof of concept, it illustrates how sensing, computation, memory, and actuation might be combined in a compact and flexible platform rather than distributed across multiple rigid components.

This integration could address one of the central limitations of current wearable electronics. Most commercial systems rely on separate sensors, processors, memory units, batteries, and communication modules. Combining these parts increases bulk, power consumption, and manufacturing complexity. An adaptive OECT could perform some signal-processing and memory functions at the point where biological data are collected, reducing the need to transmit all information to a distant processor. Lower data traffic could also help reduce energy use, an important advantage for devices intended to operate continuously on the body.

The researchers envision applications in electronic skin, wearable health monitors, soft robots, adaptive prosthetic systems, and implantable bioelectronics. In the longer term, networks of these transistors could form low-power neuromorphic systems capable of learning from physiological signals and responding to changing conditions. Dynamic compression bandages might adjust automatically as swelling changes, while electronic skins could detect injury and adapt their response in real time. The color-changing operation would add an immediate visual layer of feedback. The work, reported in ACS Nano under the title “Fully Stretchable Ionically Tunable Organic Electrochemical Transistors for Wearable Adaptive Logic Bioelectronics,” points toward a future in which wearable devices are not merely flexible, but capable of changing how they compute according to their environment.

Subject of Research: Experimental study of fully stretchable, ionically tunable organic electrochemical transistors for adaptive wearable bioelectronics.

Article Title: Fully Stretchable Ionically Tunable Organic Electrochemical Transistors for Wearable Adaptive Logic Bioelectronics.

News Publication Date: 24 June 2026.

Web References: https://doi.org/10.1021/acsnano.6c05309

References: ACS Nano, DOI: 10.1021/acsnano.6c05309.

Image Credits: Assistant Professor Hyunseok Shim, Pusan National University.

Keywords

Wearable devices, soft electronics, organic electrochemical transistors, stretchable electronics, adaptive logic, artificial synapses, neuromorphic bioelectronics, biomedical engineering, electronic skin, medical technology, sensors, soft robotics.

Ocean stirring, or the process by which ocean currents create turbulence and mix water masses, is an essential driver of the planet’s climate system. On a horizontal scale ranging from tens to hundreds of kilometers, this phenomenon is known as mesoscale horizontal stirring (MHS). It plays a pivotal role in shaping marine ecosystems by redistributing heat, nutrients, and dissolved substances such as microplastics—substances whose fate is increasingly critical for global ocean health.

Despite its importance, the intricate dynamics of MHS in polar oceans have long remained shrouded in mystery. The harsh and remote nature of polar environments restricts direct observations, while satellite data often lack the spatial resolution to capture the smaller-scale currents and eddies responsible for mixing. Moreover, traditional climate models typically do not resolve these mesoscale features adequately, limiting their ability to predict changes in oceanic stirring under future warming scenarios.

To bridge this knowledge gap, an international team led by Professor June-Yi Lee, doctoral candidate Gyuseok Yi, and Professor Axel Timmermann leveraged cutting-edge computational advancements to perform ultra-high-resolution simulations using the Community Earth System Model version 1.2.2 (CESM-UHR). These simulations, executed on the powerful Aleph supercomputer at the Institute for Basic Science in Daejeon, integrated fully coupled components representing the atmosphere, sea ice, and ocean to realistically portray interactions governing MHS.

Their analyses reveal a marked intensification of mesoscale horizontal stirring in polar regions as atmospheric CO₂ concentrations double and further quadruple, consistent with aggressive greenhouse warming pathways. This enhanced stirring arises mainly from the accelerated loss of sea ice, which exposes the ocean surface to direct wind forcing, thereby energizing the flow of ocean currents and stimulating increased turbulent activity.

In the Arctic Ocean, the retreat of sea ice unveils vast expanses of open water that become more susceptible to wind-driven mixing. This process increases eddy generation and disrupts stratification, leading to heightened horizontal stirring. Meanwhile, in the Southern Ocean, particularly along the Antarctic coast, melting glaciers contribute fresh water that alters density gradients in the ocean. These gradients reinforce currents including the Antarctic Slope Current, which, in turn, strengthens mesoscale turbulence and horizontal water parcel dispersion.

A central analytical tool employed by the team, the finite-size Lyapunov exponent (FSLE), quantifies how neighboring water parcels diverge over time — a precise measure of stirring intensity. FSLE maps illustrated a clear and persistent increase in horizontal stirring rates across both polar basins, mirroring the loss of sea ice and ecosystem exposure to dynamic environmental changes. This finding signals a potential shift in how nutrients circulate and how biological communities—plankton and fish larvae alike—are transported in these rapidly warming seas.

The cascading consequences of enhanced MHS extend beyond physical oceanography. Increased mixing can alter nutrient availability in surface waters, potentially modulating plankton blooms that comprise the base of the marine food web. Simultaneously, the redistribution of microplastics and other pollutants may accelerate their spread within these sensitive environments, posing unknown risks to marine organisms and food security.

Professor Lee emphasizes that understanding the intensification of mesoscale stirring is essential for developing robust climate adaptation policies. “Our study highlights the interconnectedness of physical changes in the ocean with biological responses and pollutant dynamics,” she notes, underscoring the importance of integrated Earth system models that can inform decision-makers seeking to mitigate climate risks.

Looking forward, the ICCP research group plans to incorporate explicit biological models of plankton and fish alongside their physical simulations. This integration aims to unravel the feedback loops between climate-driven ocean stirring and ecosystem responses, offering a more holistic view of the polar marine environment under climate change pressures.

Professor Timmermann envisions this next generation of Earth system models as transformative tools. “By coupling biological processes with climate physics at ultra-high resolutions, we will obtain unprecedented insights into how life in polar oceans adapts or succumbs to warming. This knowledge is vital for preserving biodiversity and managing marine resources,” he explains.

The emergent picture from this research underscores the accelerating pace of change in Earth’s polar frontiers. As sea ice recedes, the ocean’s internal dynamics shift towards a state of greater turbulence and mixing, reshaping the physical and biological fabric of these ecosystems. Addressing these alterations is crucial not only for scientific understanding but also for guiding international climate policy and conservation strategies.

With global CO₂ levels continuing to rise, these detailed simulations serve as a stark reminder of how interconnected the climate system truly is. The work from Pusan National University exemplifies the power of advanced computational modeling in capturing the fine-scale processes that drive large-scale environmental change, marking a significant step forward in our effort to anticipate and respond to the challenges of a warming world.

Subject of Research:
Article Title: Future mesoscale horizontal stirring in polar oceans intensified by sea ice decline
News Publication Date: 5-Nov-2025
Web References: http://dx.doi.org/10.1038/s41558-025-02471-2
References: Nature Climate Change, DOI: 10.1038/s41558-025-02471-2
Image Credits: Professor June-Yi Lee, Pusan National University, Korea
Keywords: Sea ice, Oceans, Oceanography, Ocean chemistry, Ocean physics, Ocean waves, Ocean circulation

Utilizing a high-resolution atmospheric model resolved at 2 kilometers, integrated meticulously with NASA’s Tropical Rainfall Measuring Mission (TRMM) satellite data and the MERRA-2 reanalysis datasets, the study investigates aerosol-induced modifications to convection and precipitation dynamics under different atmospheric states. The researchers focused on a striking Madden-Julian Oscillation (MJO) event from 2011, though they extended their methodology across various MJO phases and multiple years for robustness. The simulations unveiled that heavy aerosol loading consistently intensified precipitation over oceanic regions, sometimes by as much as 50%, while concurrently suppressing rainfall over adjacent land masses—a hitherto unknown phenomenon.

The core mechanism behind these transformations arises primarily from radiative forcing disparities between land and ocean surfaces influenced by aerosol presence. Aerosols induce enhanced scattering and absorption of sunlight, which preferentially cools the land areas more than the ocean. This differential cooling establishes atmospheric stability over islands, effectively suppressing convective activity on land. Conversely, the ocean remains relatively warm and unstable, fostering enhanced low-level convergence and vigorous convective processes offshore. The resultant wind patterns draw moist air seaward, further reinforcing intensified oceanic precipitation and a markedly increased sea-to-land rainfall ratio.

Professor Seo articulates, “Aerosols act like a brake on daytime heating over land, but the ocean hardly feels that brake.” The study’s sophisticated high-resolution simulations capture this interaction in unprecedented detail, revealing the spatial redistribution of moisture and energy within the lower troposphere. This insight challenges conventional paradigms that previously treated aerosol effects as spatially uniform or primarily detrimental to precipitation as a whole. Instead, this nuanced understanding illustrates complex aerosol–radiation interactions that reshape convective dynamics at regional scales.

Intriguingly, the aerosol-driven surface cooling over land not only alters spatial patterns of rainfall but also produces a pronounced delay in the diurnal cycle of precipitation on islands. The typical late afternoon convective peak shifts toward midnight, a counterintuitive effect linked to reduced solar heating during the day and subsequent nocturnal buildup of moist static energy. This temporal displacement carries significant implications for urban planning, flood management, and agricultural scheduling across densely populated zones like Jakarta and Manila, where timing of rainfall critically influences human activities and infrastructure resilience.

These aerosol effects observed through model simulations find strong corroboration in satellite data, validating the real-world significance of the mechanisms identified. Seasonal haze episodes in the Maritime Continent, often associated with regional biomass burning and industrial emissions, display similar rainfall redistribution patterns. This congruence between theory, simulation, and observation underscores the transformative potential of integrating aerosol dynamics into operational weather and climate prediction frameworks.

Beyond immediate regional impacts, the research carries profound implications for understanding and forecasting tropical atmospheric phenomena more broadly. The Maritime Continent is a critical choke point for the Madden-Julian Oscillation, which modulates weather patterns from Indian monsoons to Pacific typhoons. By elucidating how aerosols weaken land convection and modify ocean-land precipitation contrasts, the study suggests smoother MJO propagation over this region, potentially enhancing the predictability of seasonal climate variability. Such progress promises far-reaching benefits for climate risk management across Asia and beyond.

The realization that aerosol emissions can substantially rewrite precipitation geography compels a reexamination of climate models’ treatment of particulate matter. Integrating these aerosol effects with granularity will refine projections of extreme precipitation, monsoon variability, and tropical cyclone activity under future emission scenarios. Given the escalating urbanization and industrialization in Southeast Asia, this knowledge serves as a critical foundation for devising adaptive strategies against climate-induced water insecurity and disaster risk.

Professor Seo’s findings arrive at a pivotal moment when many tropical regions face mounting challenges posed by air pollution and erratic rainfall. The insights enable more precise short-term forecasting during haze episodes, allowing authorities to better orchestrate emergency responses, manage water resources prudently, and safeguard transportation and infrastructure. Furthermore, the nuanced understanding of aerosol-rainfall interactions informs public health assessments linked to air quality and hydrological variability, spotlighting the interconnectedness of atmospheric chemistry and climate dynamics.

As aerosol concentrations continue to fluctuate due to anthropogenic activity and natural events, the dynamic coupling between aerosols and tropical precipitation highlighted by this research underscores the complexity of Earth’s climate system. It elevates the urgency of incorporating multi-scale, multi-physics aerosol processes into next-generation climate and weather models to capture emergent properties vital for regional climate resilience. Ultimately, the findings herald a transformative shift in how scientists and policymakers approach tropical rainfall forecasting and adaptation in an increasingly aerosol-impacted world.

This pioneering study, published in the reputable journal npj Climate and Atmospheric Science, exemplifies the power of integrating detailed computational modeling with extensive observational datasets to unravel intricate climate processes. The Maritime Continent’s climate regime, intricately tied to global circulation and regional livelihoods, will benefit immensely from these research advances, potentially informing policies that mitigate risks and harness opportunities in a rapidly changing atmosphere.

Subject of Research: Aerosol impacts on regional precipitation patterns over the Maritime Continent, specifically oceanic intensification and diurnal cycle delay of rainfall due to aerosol-induced radiative effects.

Article Title: Aerosol effects on Maritime Continent precipitation: Oceanic intensification and land diurnal cycle delay

News Publication Date: September 25, 2025

Web References:
https://www.nature.com/articles/s41612-025-01215-5

References:
DOI: 10.1038/s41612-025-01215-5

Image Credits:
Professor Kyong-Hwan Seo, Pusan National University, Korea

Keywords:
Environmental sciences, Environmental issues, Environmental monitoring, Pollution, Rain, Air pollution, Atmospheric science, Meteorology

Despite arsenic’s well-documented toxicity in various environmental matrices, its specific behavior and interaction with forest soils remain inadequately explored. The mechanisms by which arsenic binds to, mobilizes within, and bioaccumulates from soils directly influence its ecological impact. Factors such as the chemical composition and physical properties of the soil dictate not only how arsenic moves but also its availability to soil organisms. Understanding these nuances is crucial for assessing ecosystem responses and developing remediation strategies.

A recent breakthrough study from Pusan National University, led by environmental ecologist Professor Yun-Sik Lee, delves into this intricate interplay between arsenic and forest soils. The research specifically examines how distinct soil properties regulate the mobility and bioavailability of arsenic, thereby modulating its toxicological effects on soil microfauna. Central to their investigation is the springtail species Allonychiurus kimi, a small soil-dwelling invertebrate widely recognized as a sentinel organism for soil health monitoring. By targeting this species, the study bridges the gap between soil chemistry and biological response, shedding light on arsenic’s ecotoxicity at different life stages of soil fauna.

To unravel the complex dynamics at play, Professor Lee’s team collected four forest soil types free from prior contamination. These soils underwent comprehensive physicochemical characterization, including parameters such as pH, cation exchange capacity (CEC), phosphorus availability, organic matter content, metal oxide composition, and clay percentage. This detailed profiling is indispensable, as these properties influence arsenic binding sites and chemical speciation within the soil matrix. Subsequently, soils were artificially contaminated with arsenic at concentrations ranging from 20 to 100 mg/kg. To simulate realistic environmental conditions, the soils experienced wetting and drying cycles, which affect arsenic’s redox state and mobility.

A crucial step in their methodology involved applying the Wenzel sequential extraction procedure, which fractionates arsenic into operationally defined chemical pools with varying mobility and bioavailability. Fractions F1 and F2 represent weakly bound arsenic species, highly mobile and immediately bioavailable. Fraction F3 consists of arsenic bound to amorphous iron and aluminum oxides, potentially bioavailable but more stable. Fractions F4 and F5 correspond to arsenic tightly bound to crystalline oxides and residual mineral structures, respectively, generally considered less bioavailable. This nuanced fractionation allows researchers to pinpoint which chemical forms pose the greatest risk to biota.

The biological assays exposed adult and juvenile A. kimi springtails to these prepared soils over a 28-day period. Measurement of arsenic accumulation, survival rates, and reproductive output provided vital ecotoxicological endpoints. Notably, the data revealed that newly introduced arsenic predominantly resides in the mobile fractions (F1–F3), which are readily taken up by soil organisms, leading to significant bioavailability. The research underscored how soil chemical properties intensely influence arsenic’s distribution among these fractions. Specifically, soils with higher cation exchange capacity, increased phosphorus levels, and abundant aluminum oxides tended to immobilize arsenic more effectively, reducing its toxic potential.

An intriguing dimension of the findings relates to life-stage susceptibility. Adult springtails, while accumulating arsenic, displayed remarkable tolerance with minimal mortality, suggesting physiological mechanisms that mitigate arsenic toxicity. By contrast, juvenile springtails were acutely sensitive; exposure to mobile arsenic fractions severely impaired their reproductive capacity. This marked difference underscores the critical vulnerability of early development stages within soil invertebrate populations, implying cascading effects on population dynamics and soil ecosystem functionality.

Professor Lee highlights the pivotal role of soil chemistry in mediating arsenic toxicity, suggesting that regulatory strategies should move beyond total arsenic concentration metrics. Instead, assessments must integrate speciation data and bioavailability to accurately gauge environmental risks. This paradigm shift would enable more precise ecological risk assessments, tailored to local soil conditions and specific contamination scenarios, thereby enhancing the efficacy of remediation efforts.

Furthermore, this research contributes substantially to the field of soil ecotoxicology by emphasizing life-stage specific responses and the importance of fractionated arsenic analysis. The differential sensitivity between juvenile and adult soil organisms necessitates refined bioassays that capture these nuances, potentially influencing regulatory standards for soil pollution. The study’s approach, integrating soil chemistry with biological impact assessments, models a comprehensive framework for future investigations into metal and metalloid contaminants.

The ecological implications extend beyond the springtails studied. Given the foundational role of microarthropods in nutrient cycling and soil structure maintenance, arsenic contamination could disrupt these fundamental processes, leading to broader ecosystem degradation. In forests, where soil health supports complex terrestrial food webs, protecting soil communities is critical for preserving overall biodiversity and ecosystem resilience.

In summary, the investigation by Professor Yun-Sik Lee’s team elucidates how forest soil properties—particularly CEC, phosphorus, and aluminum oxides—govern arsenic mobility and bioavailability. The distinct vulnerability of juvenile soil organisms to mobile arsenic fractions underscores the necessity of life-stage specific ecotoxicological assessments. This comprehensive research advances our understanding of arsenic-soil-organism interactions, paving the way for smarter, soil-tailored contamination risk evaluations and remedial strategies that prioritize both environmental and public health.

As global pressures on natural resources intensify and legacy mining sites continue to release toxic substances, such scientific insights are vital for framing effective environmental policies and on-the-ground management practices. Protecting the silent soil inhabitants ensures the preservation of ecosystem services that underpin human well-being, reminding us that even the smallest creatures serve as critical sentinels of environmental integrity.

Subject of Research: Animals

Article Title: Forest soil properties regulate arsenic mobility and life stage-specific ecotoxicity in Collembola: Implications for early-stage contamination risk

News Publication Date: 1-Sep-2025

References:
DOI: 10.1016/j.jhazmat.2025.139737

Image Credits:
Professor Yun-Sik Lee from Pusan National University, Korea

Keywords:
Soil science, Environmental sciences, Forestry, Environmental management, Environmental issues, Soil pollution

In recent years, the intersection of robotics and material science has garnered significant attention. Among the various developments, the utilization of origami-inspired structures has emerged as a hallmark of innovation. These structures, characterized by their ability to fold and unfold swiftly while maintaining operational integrity, are ideal for applications in aerospace, architecture, and healthcare. Unlike traditional materials like paper and thin glass, FRPs present a more robust alternative that integrates both rigidity and flexibility into a singular format.

The research team, under the direction of Associate Professor Dong Gi Seong, has embarked on a mission to address the current limitations in FRP fabrication. The proposed multi-resin dispensing process selectively incorporates rigid and flexible epoxy resins at predetermined locations within a single monolithic setup. This intricate design allows the mechanical properties to be finely tuned, enabling a dual functionality that empowers robotics with enhanced flexibility coupled with sufficient strength.

The significance of this innovation cannot be overstated. Traditionally, robotic components have been manufactured using a singular resin, which inherently limits the functional application of these parts. The dual-resin approach introduced through this study enables a revolution in how robotic limbs and components are designed. Not only does this result in lighter systems, but it also mitigates the trade-offs that engineers often face when integrating different material properties for varying functions.

As Dr. Seong elaborates, this method offers a notable enhancement in the composite’s performance characteristics. The resulting structures possess impressive metrics, such as a flexural modulus of 6.95 GPa in rigid segments and a mere 0.66 GPa in foldable areas. This stark difference underscores the potential applications in environments that require reliability without compromising on the ability to manipulate and adapt to circumstances. The triangulated cylindrical origami structure fabricated by the team stands as a testament to their ingenuity, showcasing the practical benefits of integrating advanced composite materials within robotic frameworks.

More than just a novel technique, the implications of this research broaden the horizons for innovation across numerous fields. By utilizing composite materials that can adjust their rigidity and flexibility dynamically, robotic engineering moves a step closer to realizing transformational concepts, including humanoid robots and multi-functional robotic arms. This adaptability paves the way for robots that can transition from rigid motions to soft, nuanced movements, reflecting natural biological systems.

In addition to robotics, the applications extend into various futuristic technologies. This includes the potential for deploying solar panels in space, enabling structures that can compactly store and efficiently unfold to harness solar energy. Furthermore, the ability to create foldable electronics might usher in advancements in consumer technology, leading to more compact, portable devices that retain high functional capabilities.

The potential applications of this new FRP technology are not limited to terrestrial uses. Dr. Seong suggests it could also find significant roles in military and emergency response scenarios, particularly with durable, foldable shelters that are easy to transport and deploy in disaster situations. The advancements made here could directly impact the efficiency and effectiveness of response strategies when unexpected events occur, saving lives and resources alike.

Moreover, the fascinating capabilities of this technology could entail a step toward next-generation vehicles. Imagine a transport system equipped with wheels that can adapt in real-time to various terrains and conditions, enhancing mobility and reducing energy consumption. The promise of achieving such adaptability in vehicle design creates a ripple effect, influencing industries striving for innovation and efficiency.

As robotics and associated technologies continue to evolve, the groundwork laid by this research could lead to significant advancements in how robots are designed, constructed, and utilized. The fusion of soft and rigid components represents a paradigm shift in understanding what is possible in robotic engineering.

Another aspect worth mentioning is the commercialization of this technology. Industries are likely to observe an influx of interest from manufacturers and developers eager to integrate tailored FRPs into their existing designs or create entirely new applications. The ingenuity showcased in this research highlights a clear pathway toward achieving unprecedented functionality and performance in commercial robotics.

The journey of this research is far from over. As follow-up studies and practical applications emerge, the scientific community will likely seek to refine and innovate even further, making robotic solutions increasingly sophisticated. The collaborative efforts at Pusan National University set an example for interdisciplinary teams working at the cutting edge of science, emphasizing the critical role that material innovations play in the advancement of technology.

As we stand on the brink of this new era in robotics, the work of Professor Dong Gi Seong and his team shines as an emblem of potential breakthroughs that await us. Their commitment to exploration and innovation is a reminder that the fusion of research, technology, and creativity will continue to shape the future of robotics and beyond.

Subject of Research:
Fiber-Reinforced Polymer for Advanced Monolithic Rigid–Soft Robotics Applications

Article Title:
Deployable Fiber-Reinforced Polymer for Advanced Monolithic Rigid–Soft Robotics Applications

News Publication Date:
1-Oct-2025

Web References:
https://www.sciencedirect.com/science/article/pii/S1359836825006602

References:
[1] DOI: 10.1016/j.compositesb.2025.112754

Image Credits:
Dong Gi Seong from Pusan National University

Keywords

Robotics, Engineering, Artificial Intelligence, Electronics, Polymer Engineering, Composite Materials

Bacteria inhabit nearly every ecological niche, thriving due to their rapid proliferation capabilities. While many bacterial strains, including LAB, contribute positively to human health and food preservation, pathogenic bacteria like Escherichia coli and Staphylococcus aureus persist as significant threats to public health worldwide. The escalating prevalence of antimicrobial resistance among these pathogens has severely undermined the efficacy of conventional antibiotics, demanding the exploration of alternative antibacterial strategies grounded in precision and safety.

Among promising alternatives, endolysins—specialized enzymes capable of degrading bacterial cell walls—have attracted considerable attention. These bacteriophage-derived or engineered enzymes exhibit remarkable specificity toward target bacteria, minimizing off-target effects and ecological disruption. Despite their potential, widespread adoption of endolysins is constrained by technical barriers including complex production processes, instability under physiological conditions, and rapid enzymatic degradation in vivo or during storage, which curtail their therapeutic utility.

Addressing these challenges, the Pusan National University team turned to extracellular vesicles, nanoscale lipid bilayer-enclosed particles naturally secreted by cells that ferry bioactive molecules such as proteins and nucleic acids between cells. By harnessing EVs derived from Lacticaseibacillus paracasei, a LAB species recognized for its probiotic properties, the researchers engineered a platform that displays pathogen-targeting endolysins on the EV surface, enhancing delivery efficiency, stability, and specificity.

Critical to the success of this platform was the identification of a previously uncharacterized surface-displaying protein (SDP) inherently present on the EV membranes of L. paracasei. Comprehensive proteomic analyses combined with advanced bioinformatics tools revealed thirteen distinct SDPs associated with these EVs, among which a novel protein designated LP-SDP3 was singled out for its conserved structure and function across homologous proteins in E. coli and other LAB strains. This evolutionary conservation suggests that LP-SDP3 plays a fundamental role in EV biology across multiple bacterial taxa.

Professor Kwang-sun Kim, lead investigator of the study, highlighted the novelty of this discovery: “To date, surface-displaying proteins from the EVs of lactic acid bacteria have not been characterized. The identification of LP-SDP3 not only fills this knowledge gap but opens avenues to exploit these natural vesicles for targeted antimicrobial delivery in a way not previously possible.” This insight paved the way for functionalizing EVs with therapeutic enzymes.

Building upon this foundation, the team bioengineered EVs to present PlyF307_SQ-8C, a potent endolysin specifically active against S. aureus. Through molecular fusion of PlyF307_SQ-8C to the LP-SDP3 anchor protein, the EVs gained the ability to selectively bind and disrupt S. aureus bacteria with high affinity and efficacy. Importantly, these engineered extracellular vesicles demonstrated remarkable resilience to environmental stresses, maintaining antimicrobial activity across variable temperature and pH conditions—a critical advantage for clinical and storage applications.

Another significant finding was that the EV-based delivery system did not induce antimicrobial resistance in S. aureus, a stark contrast to traditional antibiotics that often promote resistant strains. This phenomenon addresses a critical global health concern and aligns with the growing demand for therapeutics that circumvent resistance mechanisms. Furthermore, safety evaluations indicated that the engineered EVs possess a toxicity profile comparable to, or better than, purified endolysin preparations, underscoring their promise as safe antibacterial agents.

From a manufacturing perspective, Prof. Kim emphasized the scalability and economic viability of this approach. The ability to cultivate LAB at industrial scales combined with the elimination of costly protein purification steps embedded in conventional enzyme therapies could dramatically reduce production expenses. This scalability positions the technology favorably for widespread adoption, especially in resource-limited settings.

Looking ahead, the researchers envision transformative applications for their technology spanning clinical medicine, food safety, and biotechnology. Engineered EVs could function as next-generation antibiotics, offering precision treatment options for recalcitrant infections while mitigating collateral damage to beneficial microbiota. Additionally, their potential in food preservation could suppress harmful contamination without reliance on chemical preservatives, aligning with consumer preferences for natural and sustainable solutions.

The interdisciplinary nature of this work, integrating microbiology, bioengineering, and nanotechnology, exemplifies how deep fundamental insights into bacterial vesicle biology can yield innovative therapeutic platforms. The discovery of LP-SDP3 and its functional exploitation marks a milestone in synthetic biology and extracellular vesicle research, enriching our toolkit against antibiotic-resistant pathogens.

Collectively, this research embodies a paradigm shift from traditional antibiotic strategies to bioengineered, smart delivery systems harnessing nature’s own nanoscale machinery. If realized in clinical practice, such EV-based antimicrobial agents could redefine infection management protocols, reduce the global burden of resistant bacteria, and catalyze the development of sustainable biotherapeutics.

In conclusion, the pioneering work by Pusan National University researchers underscores the untapped potential of LAB-derived extracellular vesicles as versatile carriers for targeted endolysin delivery. By bridging molecular discovery with applied bioengineering, this approach heralds a new era of precision antimicrobial therapy characterized by efficacy, safety, and resistance mitigation.

Subject of Research: Cells

Article Title: Surface-displaying protein from Lacticaseibacillus paracasei–derived extracellular vesicles: Identification and utilization in the fabrication of an endolysin-displaying platform against Staphylococcus aureus

News Publication Date: 15-May-2025

References: DOI: 10.1016/j.cej.2025.162196

Image Credits: Professor Kwang-sun Kim from Pusan National University, Korea

Keywords: Antibiotic resistance, Bioengineering, Drug delivery, Synthetic biology, Antibiotics, Proteomics, Biotechnology, Bacteriophages, Extracellular proteins, Staphylococcus

The pioneering work, spearheaded by Professor Jeongbin Park and co-first authors Abyot Melkamu Mekonnen and Kang Seong, introduces an innovative computational platform that acknowledges that CRISPR off-target activity is not a one-size-fits-all phenomenon but varies substantially based on allele-specific sequence context. This insight forms the foundation of Variant-aware Cas-OFFinder, which accepts phased single-sample Variant Call Format (VCF) files containing detailed genetic variant information. The tool reconstructs allele-specific genome sequences by incorporating single nucleotide polymorphisms (SNPs) along with insertions and deletions from the individual’s genotype data. This haplotype-level reconstruction enables the algorithm to perform off-target site predictions that reflect the unique genomic landscape of each allele, thereby offering unprecedented precision in identifying potential CRISPR editing risks.

While existing bioinformatics tools such as Cas-OFFinder and CRISPRitz provide rapid scanning of reference genomes for potential off-target sites, their reliance on canonical reference sequences inevitably overlooks individual-specific variants that may generate novel off-target loci or mask others. Variant-aware Cas-OFFinder transcends this limitation by enabling variant-aware scanning. By considering the full spectrum of small variants, the tool identifies off-target sites attributable specifically to insertions and deletions, which are often neglected in prior analyses. This significantly elevates the sensitivity and specificity of off-target prediction, setting a new standard for computational genome editing safety assessments.

Equipped with robust GPU acceleration compatibility, Variant-aware Cas-OFFinder supports resource-intensive haplotype-level analyses while maintaining practical computational efficiency. The tool currently accommodates genetic data from an impressive range of 557 species and supports 40 Protospacer Adjacent Motif (PAM) types, showcasing remarkable versatility across biological domains. This extensibility opens avenues for personalized genome editing applications not only in human health but also in agriculture and environmental sciences, where accurate off-target prediction tailored to diverse species and cultivars is vital.

Critically validating their tool, the Pusan National University team applied Variant-aware Cas-OFFinder to human and sweet pepper (Capsicum annuum) genomes, utilizing both public datasets and cultivar-specific sequencing information. In human samples, the analysis uncovered potential off-target sites on chromosome 10 that were absent from the standard human reference genome, highlighting the necessity of including personal genomic variation for reliable CRISPR design in clinical contexts. In the agricultural context, the tool identified allele-specific off-targets within sweet pepper cultivars, demonstrating how such haplotype-aware analyses can facilitate precision breeding strategies and accelerate the development of improved plant varieties with minimized genomic risks.

Although Variant-aware Cas-OFFinder presently does not handle large structural variants — which remain a challenging frontier due to their complexity and length — its focus on small variants already fills a crucial void in current methodologies. The tool’s flexible customization via YAML configuration files caters to advanced users aiming to tailor off-target detection parameters to their specific research requirements, enhancing its accessibility and utility across a broad user base.

Fundamental to the philosophy of this project is the assertion from Prof. Park that genome editing must be as individualized as the very genetic material it seeks to modify. This resonates with emerging trends toward personalized medicine, where therapeutic interventions increasingly take into account patient-specific genetic landscapes. By fostering precise off-target prediction at the haplotype level, Variant-aware Cas-OFFinder offers a technological foundation for safer and more ethical clinical genome editing, reducing risks of unintended mutagenesis that could lead to oncogenic or other adverse outcomes.

The user experience has been carefully designed to accommodate a broad spectrum of users. Scientists and clinicians can access Variant-aware Cas-OFFinder either through a user-friendly web interface for quick analyses or via a command-line version that integrates seamlessly with bioinformatics pipelines. To promote transparency and community-driven development, all related source code, benchmarking tools, and example datasets have been made openly available on GitHub and Zenodo repositories, aligning with open science principles.

Balancing computational complexity with predictive accuracy, the haplotype-level analyses implemented by Variant-aware Cas-OFFinder may introduce modest performance overheads compared to earlier tools limited to reference genomes. However, this trade-off is justified by the substantial increase in result fidelity and the capability to reveal personalized off-target profiles otherwise obscured in traditional analyses. This paradigm shift embraces the genomic intricacies of individuals rather than forcing them into a standardized mold.

The implications of this tool extend beyond academic research, heralding transformative possibilities in therapeutic genome editing. CRISPR therapies aiming to correct deleterious mutations in patients’ cells can now be refined to avoid off-targeting that may jeopardize patient safety. Similarly, agricultural biotechnologists can harness these insights to safely engineer crop genomes, tailoring modifications to specific cultivars’ genetic backgrounds and thus enhancing both efficacy and regulatory compliance.

As genome editing technologies continue to mature, the integration of variant-aware computational tools like Cas-OFFinder will be indispensable for minimizing off-target effects and realizing the full potential of precision medicine and sustainable agriculture. This innovation from Pusan National University marks a vital step towards the ultimate goal of personalized genome engineering that respects individual genetic uniqueness while maximizing safety and efficacy.

In summary, Variant-aware Cas-OFFinder represents a major advance in the computational genomics field by offering a haplotype-resolved, variant-informed approach to CRISPR off-target prediction. Its development addresses longstanding limitations of previous tools, builds a robust platform adaptable to hundreds of species, and delivers critical insights for both biomedical and agricultural genome editing applications. As the scientific community embraces such sophisticated tools, the promise of CRISPR as a truly precise genome engineer comes closer to fruition.

Subject of Research: Not applicable

Article Title: Variant-aware Cas-OFFinder: web-based in silico variant-aware potential off-target site identification for genome editing applications

News Publication Date: 8-May-2025

References: DOI: 10.1093/nar/gkaf389

Image Credits: Credit: Professor Jeongbin Park from Pusan National University, Korea

Keywords: CRISPRs, Genome editing, Computational biology, Bioinformatics, Genetic variation, Technology, Health and medicine, Plant genomes, Haplotypes

The adipose tissue, often overlooked as merely a reservoir of energy, serves a far more complex role as an endocrine organ. It releases various bioactive molecules that can facilitate the repair of other tissues, notably skin. This research underscores the potential for reengineering adipose tissues, making them powerful allies in regenerating damaged organs. The advent of 3D bioprinting represents a significant turning point, allowing scientists to fabricate engineered organs and tissues that mimic the intricate structures found in nature.

Historically, methods of tissue biofabrication have struggled to replicate the unique architecture and densely packed lipid droplets characteristic of natural adipose tissues. Assistant Professor Kim and his lab recognized this challenge and took it upon themselves to fill the void with an innovative biofabrication technique. Their study, available online since February 2, 2025, introduces a hybrid bioink composed of 1% adipose-derived decellularized extracellular matrix and 0.5% alginate. This blend specifically curtails the migration of preadipocytes, while simultaneously promoting their differentiation into functional fat cells.

In scientific terms, the study gives insight into the threshold diameter for adipose units that must be adhered to—preferably less than or equal to 600 µm—to ensure adequate nutrient and oxygen delivery within the bioprinted constructs. The importance of optimal spacing—set at a maximum of 1000 µm—between the adipose units is emphasized as a crucial factor that fosters adipogenesis. The implications of this arrangement are profound, leading to enhanced paracrine signaling which, in turn, facilitates a flourishing environment for skin cell migration.

The in vitro component of their research revealed striking results through modulating expression levels of cell migration-related proteins. This highlights how the bioprinted adipose tissues not only serve their standard role but also take on an active role in skin regeneration processes. The proteins involved—MMP2, COL1A1, KRT5, and ITGB1—play significant roles in wound healing and tissue repair mechanisms, effectively turning the engineered tissues into active agents of regeneration.

As the research progressed into in vivo studies, the team developed a tissue assembly that incorporated both adipose and dermal modules. This assembly was subsequently implanted into mouse models with skin wounds. The findings from this phase demonstrated that the novel tissue assembly accelerated wound healing significantly, characterized by re-epithelialization and enhanced remodeling of tissues, not to mention improved vascularization. The expression of skin cell differentiation-related proteins was meticulously regulated, validating the functional efficacy of this groundbreaking approach.

The current advancements in bioprinting technology signal a paradigm shift towards a future where customized tissue engineering is commonplace. Researchers expect a burgeoning market for personalized bioprinting systems as healthcare institutions seek innovative methods tailored to individual patient needs. With increased adoption of these personalized solutions, the scope for treating various ailments—especially chronic wounds like diabetic ulcers, pressure sores, and burns—expands drastically.

Furthermore, the implications regarding regenerative medicine arise not merely from the ability to heal wounds, but also from the prospect of improving fat grafting procedures. Currently, fat grafting techniques face challenges such as low survival rates and gradual absorption of grafted tissues. However, the hybrid bioinks developed by Kim’s team show promise in enhancing both endocrine function and overall survival rates among adipose cells, potentially offering a solution to overcome these limitations.

In closing, the study conducted at Pusan National University demonstrates the promising potential of 3D bioprinted endocrine tissues for skin regeneration. As stated by lead author Jae-Seong Lee, the significant impact of this research provides evidence of the practical applications in regenerative medicine, creating optimism for future methods of treatment in various clinical settings. The incorporation of bioprinted adipose tissues as a standard in healthcare innovation signals a transformative period in medical science, fundamentally altering our approaches to healing and restoration.

Ultimately, this pioneering research sheds light on a future where 3D bioprinting does not merely fill gaps but innovates and refines the methodologies of regenerative medicine. As the study continues to gain traction, it holds potential not only for academic exploration but also for real-world healthcare solutions that align with the growing demand for personalized medicine, opening doors to unprecedented therapeutic pathways.

Subject of Research: Animals
Article Title: 3D Bioprinting-Assisted Tissue Assembly of Endocrine Adipose Units for Enhanced Skin Regeneration
News Publication Date: February 2, 2025
Web References: Advanced Functional Materials DOI
References: 10.1002/adfm.202419680
Image Credits: Byoung Soo Kim from National Pusan University, Korea

Keywords: Adipose tissue, Regenerative medicine, Skin regeneration, Tissue regeneration, Endocrine system, 3D bioprinting.

To create an accurate simulation of this catastrophic event, the researchers utilized an advanced climate model capable of illustrating the effects of a medium-sized asteroid, specifically one comparable in size to Bennu, which spans roughly 500 meters in diameter. The focal point of this model is the colossal release of 100 to 400 million tons of dust into the atmosphere as a consequence of the asteroid’s collision with Earth. This dust, serving as a proxy for the debris discharged during an actual impact, has dramatic implications for climate dynamics on a global scale.

Upon running multiple simulations using the ICCP’s powerful supercomputer Aleph, researchers observed stark disruptions to the climate and ecological systems, particularly within the initial years following the impact. The findings indicate that such dust injections could lead to global surface cooling of up to 4 degrees Celsius, which would be accompanied by diminished rainfall—an estimated decrease of 15%. These shifts would threaten agricultural systems worldwide and may precipitate mass starvation events.

However, the study’s authors found that the impact of an asteroid collision would not yield uniform consequences across all ecosystems. While terrestrial plant life suffers considerably from the abrupt "impact winter" characterized by reduced sunlight and unfavorable growing conditions, the oceanic environment reveals a more complex and nuanced response. Specifically, plankton growth demonstrated a remarkably resilient recovery within a short span. Unlike terrestrial ecosystems that may take years to rebound, marine ecosystems, particularly those relevant to plankton, could bounce back within just six months following the dust injection.

This remarkable resilience is likely tied to the nutrient dynamics initiated by the dust itself. The iron content in the dust becomes a crucial factor, as iron is an essential nutrient for algal species in nutrient-scarce ocean regions—including areas like the Southern Ocean and eastern tropical Pacific—where its natural availability is low. The simulations indicated that the nutrient-rich, dust-laden atmosphere could catalyze unprecedented algal blooms in these coastal environments.

The study further discusses how these resilient blooms of phytoplankton could provide a crucial buffer against the food security challenges posed by the loss of terrestrial productivity. Given the importance of phytoplankton as the foundation of marine food webs, their enhanced growth post-collision would not only sustain local marine life but may further propagate into larger ecological systems. As the growth of these algae attracts zooplankton—small marine predators—an intricate feedback loop could emerge wherein the marine ecosystem temporarily exceeds its ecological baseline.

The implications of such events extend beyond biological responses; they hold profound ramifications for human societies and evolutionary trajectories. The researchers speculate that early humans may have already faced significantly disruptive geological events throughout prehistory, with asteroid collisions potentially interlinking with the evolution of our ancestors. This historical inquiry into how our forebears adapted to sudden climatic shifts underscores the interconnectedness of cosmic events and human evolution.

Moreover, understanding the environmental consequences of future asteroid impacts becomes increasingly essential as humanity tracks near-Earth objects. The statistical occurrence rate of medium-sized asteroids suggests that collisions transpire approximately every 100,000 to 200,000 years. For a world largely unprepared for such catastrophic events, the research underscores the urgent necessity for proactive measures, encompassing planetary defense strategies aimed at deflecting potentially hazardous asteroids.

In conjunction with the modeling findings, the next phase of the ICCP researchers’ work anticipates a contemporary look into the early human response to asteroid impacts. They intend to deploy agent-based computer models to simulate individual human behaviors, life cycles, and resource acquisition strategies following such transformative ecological shocks. This interdisciplinary approach aims to integrate climate science with social dynamics, bridging the gap between environmental science and human resilience.

As the team prepares their findings for publication, their work stands to instigate significant discussions in both the scientific community and among lay audiences about our planet’s vulnerability to cosmic events. The multifaceted insights provided by this study concerning asteroids and their potential impact on Earth are invaluable. Not only do they enrich our understanding of climate science, but they also compel society to consider the long-term repercussions of such astronomical events on our existence.

Researchers have made it abundantly clear that understanding the past is fundamental in preparing for the future. As they work towards illuminating the details surrounding ancient asteroid impacts, they are embarking on a journey that not only recognizes the magnitude of these cosmic occurrences but also allows us to glean lessons from our ancestors’ experiences. Armed with this new knowledge, humanity can cultivate a deeper appreciation for the fragility of our planet and the interconnectivity of cosmic phenomena and terrestrial life.

In summary, the current endeavor undertaken by the ICCP represents a significant leap in understanding the multifaceted responses to asteroid impacts, focusing on climate dynamics and ecological interrelationships. This innovative study not only enhances our awareness of cosmic hazards but also equips us with critical insights that could steer our strategies moving forward as a species.

Subject of Research: Climatic and ecological responses to asteroid collisions
Article Title: Climatic and ecological responses to Bennu-type asteroid collisions
News Publication Date: 5-Feb-2025
Web References: Link to DOI
References: (To be added)
Image Credits: Institute for Basic Science

Keywords

Climate modeling, Asteroids, Planet Earth, Marine ecosystems, Marine plants, Supercomputing, Weather simulations