Natural Organisms Research Articles

Nanofluidic Membrane-Assisted Organic Electrochemical Transistors for Bioinspired Gustatory Sensation Based on Selective Cation Transport.

Natural organisms have evolved precise sensing systems relying on unique ion channels, which can efficiently perceive various physical/chemical stimuli based on ionic signal transmission in biological fluid environments. However, it is still a huge challenge to achieve extensive applications of the artificial counterparts as an efficient wet sensing platform due to the fluidity of the working medium. Herein, nanofluidic membranes with selective cation transport properties and solid-state organic electrochemical transistors (OECTs) with amplified signals are integrated together to mimic human gustatory sensation, achieving ionic gustatory reagent recognition and a portable configuration. Cu-HHTP nanofluidic membranes with selective cation transport through their uniform micropores are constructed first, followed by assembly with OECTs to form the designed nanofluidic membrane-assisted OECTs (nanofluidic OECTs). As a result, they can distinguish typically ionic gustatory reagents, and even ionic liquids (ILs), demonstrating enhanced gustatory perception performance under a wide concentration range (10-7-10-1m) compared with those of conventional OECTs. The linear correlations between the response and the reagent concentration further indicate the promising potential for practical application as a next-generation sensing platform. It is suggested that nanofluidic membranes mediated intramembrane cation transport based on the steric hindrance effect, resulting in distinguishable and improved response to multiple ions.

Developing skills for a healthy lifestyle by using interactive methods in teaching Biology and Health Education

Abstract The aim of the article is to present the results of using interactive methods in the teaching of Biology and Health Education to 7th grade students for developing skills for a healthy lifestyle. The discussion is based on the topics: “The role of prokaryotic organisms in nature and their importance for man”, “The role of unicellular eukaryotic organisms in nature and their importance for man”, and “Talus plants. Seaweed”. The discussion is supported by fragments of lessons in which interactive methods are used – the method of associations through creating mind maps, discussion, case study, and role play. As a result of using of interactive methods, students develop key competencies for maintaining their own health and the health of society as a whole.

Potential of fructans as natural cryoprotectant agents in plant cryopreservation: concept validation on Arabidopsis thaliana L.

BACKGROUND: Today, synthetic chemicals are used in vitrification solutions for cryopreservation studies to mimic natural cryoprotectants that supply tolerance to organisms in nature against freezing stress. In the case of plants, PVS2, containing glycerol, dimethyl sulfoxide (Me2SO), ethylene glycol and sucrose, is considered as the golden standard for successful cryopreservation. However, Me2SO can generally cause toxicity to certain plant cells, adversely affecting viability after freezing and/or thawing. Hence, the replacement (or substantial reduction) of Me2SO by cheap, non-toxic and natural cryoprotectants became a matter of high priority to vitrification solutions or reducing their content gained escalating importance for the cryopreservation of plants. Fructans, sucrose derivatives mainly consisting of fructose residues, are candidate cryoprotectants. OBJECTIVE: Inspired by their protective role in nature, we here explored, for the first time, the potential of an array of 8 structurally different fructans as cryoprotectants in plant cryopreservation. MATERIALS AND METHODS: Arabidopsis thaliana L. seedlings were used as a model system with a one-step vitrification method. PVS2 solutions with different Me2SO and fructan contents were evaluated. RESULTS: It was found that branched low DP graminan, extracted from milky stage wheat kernels, led to the highest recovery (85%) among tested fructans with 12.5% Me2SO after cryopreservation, which was remarkably close to the viability (90%) observed with the original PVS2 containing 15% Me2SO. Moreover, its protective efficacy could be further optimized by addition of vitamin C acting as an antioxidant. CONCLUSION: Such novel formulations offer great perspectives for cryopreservation of various crop species.

Bioinspired Genetic and Chemical Engineering of Protein Hydrogels for Programable Multi-Responsive Actuation.

Protein hydrogels with tailored stimuli-responsive features and tunable stiffness have garnered considerable attention due to the growing demand for biomedical soft robotics. However, integrating multiple responsive features toward intelligent yet biocompatible actuators remains challenging. Here, a facile approach that synergistically combines genetic and chemical engineering for the design of protein hydrogel actuators with programmable complex spatial deformation is reported. Genetically engineered silk-elastin-like proteins (SELPs) are encoded with stimuli-responsive motifs and enzymatic crosslinking sites via simulation-guided genetic engineering strategies. Chemical modifications of the recombinant proteins are also used as secondary control points to tailor material properties, responsive features, and anisotropy in SELP hydrogels. As a proof-of-concept example, diazonium coupling chemistry is exploited to incorporate sulfanilic acid groups onto the tyrosine residues in the elastin domains of SELPs to achieve patterned SELP hydrogels. These hydrogels can be programmed to perform various actuations, including controllable bending, buckling, and complex deformation under external stimuli, such as temperature, ionic strength, or pH. With the inspiration of genetic and chemical engineering in natural organisms, this work offers a predictable, tunable, and environmentally sustainable approach for the fabrication of programmed intelligent soft actuators, with implications for a variety of biomedical materials and biorobotics needs.

Beyond Color Boundaries: Pioneering Developments in Cholesteric Liquid Crystal Photonic Actuators.

Creatures in nature make extensive use of structural color adaptive camouflage to survive. Cholesteric liquid crystals, with nanostructures similar to those of natural organisms, can be combined with actuators to produce bright structural colors in response to a wide range of stimuli. Structural colors modulated by nano-helical structures can continuously and selectively reflect specific wavelengths of light, breaking the limit of colors recognizable by the human eye. In this review, the current state of research on cholesteric liquid crystal photonic actuators and their technological applications is presented. First, the basic concepts of cholesteric liquid crystals and their nanostructural modulation are outlined. Then, the cholesteric liquid crystal photonic actuators responding to different stimuli (mechanical, thermal, electrical, light, humidity, magnetic, pneumatic) are presented. This review describes the practical applications of cholesteric liquid crystal photonic actuators and summarizes the prospects for the development of these advanced structures as well as the challenges and their promising applications.

The use of phages for the biosynthesis of metal nanoparticles and their biological applications: A review.

Nowadays, the use of biological methods of synthesis of nanoparticles as substitutes for methods that use high energy and consumption of expensive and dangerous materials is of interest to researchers all over the world. Biological methods of synthesising metal nanoparticles are very important because they are easy, affordable, safe, environmentally friendly and able to control the size and shape of nanoparticles. One of the methods that is of interest today is the use of bacteriophages as the most abundant organisms in nature in the synthesis of metal nanoparticles. Nanomaterials biosynthesized from phages have shown various clinical applications, including antimicrobial activities, biomedical sensors, drug and gene delivery systems, cancer treatment and tissue regeneration. Therefore, the purpose of this review is to investigate the biosynthesis of metal nanoparticles with phages and their biomedical applications.

Voxel Design of Grayscale DLP 3D-Printed Soft Robots.

Grayscale digital light processing (DLP) printing is a simple yet effective way to realize the variation of material properties by tuning the grayscale value. However, there is a lack of available design methods for grayscale DLP 3D-printed structures due to the complexities arising from the voxel-level grayscale distribution, nonlinear material properties, and intricate structures. Inspired by the dexterous motions of natural organisms, a design and fabrication framework for grayscale DLP-printed soft robots is developed by combining a grayscale-dependent hyperelastic constitutive model and a voxel-based finite-element model. The constitutive model establishes the relationship between the projected grayscale value and the nonlinear mechanical properties, while the voxel-based finite-element model enables fast and efficient calculation of the mechanical performances with arbitrarily distributed material properties. A multiphysics modeling and experimental method is developed to validate the homogenization assumption of the degree of conversion(DoC) variation in a single voxel. The design framework is used to design structures with reduced stress concentration and programmable multimodal motions. This work paves the way for integrated design and fabrication of functional structures using grayscale DLP 3Dprinting.

"Cloth-to-Clothes-Like" Fabrication of Soft Actuators.

Inspired by adaptive natural organisms and living matter, soft actuators appeal to a variety of innovative applications such as soft grippers, artificial muscles, wearable electronics, and biomedical devices. However, their fabrication is typically limited in laboratories or a few enterprises since specific instruments, strong stimuli, or specialized operation skills are inevitably involved. Here a straightforward "cloth-to-clothes-like" method to prepare soft actuators with a low threshold by combining the hysteretic behavior of liquid crystal elastomers (LCEs) with the exchange reaction of dynamic covalent bonds, is proposed. Due to the hysteretic behavior, the LCEs (resemble "cloth") effectively retain predefined shapes after stretching and releasing for extended periods. Subsequently, the samples naturally become soft actuators (resemble "clothes") via the exchange reaction at ambient temperatures. As a post-synthesis method, this strategy effectively separates the production of LCEs and soft actuators. LCEs can be mass-produced in bulk by factories or producers and stored as prepared, much like rolls of cloth. When required, these LCEs can be customized into soft actuators as needed. This strategy provides a robust, flexible, and scalable solution to engineer soft actuators, holding great promise for mass production and universal applications.

FUNCTIONING OF MICROORGANISMS IN THE RHIZOSPHERE OF PLANTS

The functioning of living organisms in nature is possible only due to active interaction with microbiota. It is typical for phytobionts, the microbial cenosis of which is even more diverse. Plants contribute to the spread of microorganisms in the rhizosphere by releasing root exudates. The chemical composition of these exudates varies in different plant species and depends on the significant number of factors that affect their growth and development. The components of the plant root exudates stimulate expansion in the rhizosphere of microorganisms, useful for the plant growth. This microbiota improves the mineral life of plants considerably, stimulating their growth with biologically active compounds, increasing the availability of a number of microelements for them, protecting the growth of plants from phytopathogens and phytophages. It provides significant stimulation for the growth and development of phytobionts. It has been shown that microbial groups in the rhizosphere can induce some changes in the composition of plant root exudates.

Dynamic model of changes in the trophic structure of an ecosystem affected by chronic radiation exposure

The conceptual dynamic ecosystem model was developed to evaluate the self-organization of trophic structure in ecosystems during the course of biogenic succession. This model was applied to analyze the possible changes in the ecosystem under impact of the anthropogenic physical stressor – chronic exposure to ionizing irradiation. The model predicts that amount of the limiting biogenic nutrient in the environment can modify the ecological effects of ionizing radiation. Negative effects of the chronic exposure are less significant in ecosystems with high food supply. The model does not show presence of any ecological effect of radiation at the exposure rates less than the derived consideration reference levels, obtained by International Commission on Radiological Protection for individual nature organisms. If the dose rates are higher than those levels, radiation exposure can affect ecological interactions between species. The model shows that environmental hormesis can exist in the ecosystems, impacted by the chronic radiation exposure. The reason of this effect is change of the ecological coefficients (for example, decrease of the predation rate), which in the certain range of parameters leads to the increase of biomasses of all species at the same amount of the limiting biogenic nutrient in ecosystem. Trigger regimes exist in the model ecosystem with mixed-feeding consumers. Within the trigger area, the realization of a particular trophic structure depends on initial species biomasses. A hysteresis phenomenon exists in such ecosystems, which means that the successive changes in the trophic structures realized following the increase of the influencing factor are not reproduced in the same order if the influencing factor was gradually decreased back to its previous values. The model predicts for this case, that the radioactively contaminated ecosystem does not necessarily return to its initial trophic structure, despite the dose rate decreases to the initial levels.

Directional liquid dynamics on superwetting interfaces

Directional liquid dynamics show significant interest across various fields, including energy, environmental remediation, water harvesting, microfluidics, and heat transfer. Nature creatures have developed remarkable abilities to manipulate liquid through their distinct surface structures and chemical compositions, offering valuable insights for human endeavors. Understanding the fundamental principles governing liquid dynamics at the interfaces of liquids, air, and solids is crucial for developing novel technologies and solutions in diverse domains. By elucidating the underlying mechanisms of directional liquid dynamics in natural organisms, we can inspire innovative approaches for practical applications. This review aims to provide a comprehensive understanding of directional liquid dynamics by (1) exploring the fundamental principles governing liquid dynamics at interfaces, (2) introducing the underlying mechanisms of directional liquid dynamics in representative natural organisms, (3) presenting a range of innovations and applications inspired by natural phenomena, and (4) offering our insights into the current unresolved questions and persistent challenges within the realm of directional liquid dynamics on superwetting interfaces. By delineating these objectives, we aim to contribute to the advancement of knowledge in this critical area and pave the way for future research and technological developments.

Characterization and Mechanism Analysis of Sugar Transporter Protein Obtained from Monascus pilosus

Sugar transporter protein family is very common among different organisms in nature and plays a key role in the transportation, absorption, and synthesis of secondary metabolites. To investigate the functional characteristics of sugar transporter proteins in Monascus pilosus, cDNA sequence of sugar transporter protein gene MpST collected from M. pilosus CICC 5045 was cloned in this research. Furthermore, bioinformatics methods and molecular docking techniques were applied to analyze MpST protein. The obtained results revealed that the coding region of MpST was 1677 bp in length, which coded 558 amino acids, and it was a stable protein. Phylogenetic tree analysis found a close relationship between MpST and two other proteins from M. purpureus (BDD61243.1 and TQB74099.1). Bioinformatics analyses indicated that this protein is a hydrophilic protein with 11 transmembrane domains and its functional domains were mainly consisted of the conserved domains of major facilitator superfamily (MFS) and sugar transporter proteins, suggesting that this protein belonged to MFS transporter protein family. Molecular docking results suggested that the receptor protein could spontaneously bind with high affinity to small molecular ligands such as galactose, raffinose, glucose, xylose, and maltose. From the above analyses, it was predicted that this protein might have good transport function for the above five sugars. This study lays the foundation for further in-depth research on the functions and applications of this protein.

A bionic mimosa soft robot based on a multi-responsive PNIPAM-PEGDA hydrogel composition.

Deformation plays a vital role in the survival of natural organisms. One example is that plants deform themselves to face the sun for sufficient sunlight exposure, which allows them to produce nutrients through photosynthesis. Drawing inspiration from nature, researchers have been exploring the development of 3D deformable materials. However, the traditional approach to manufacturing deformable hydrogels relies on complex technology, which limits their potential applications. In this study, we simulate the stress variations observed in the plant tissue to create a 3D structure from a 2D material. Using UV curing technology, we create a single-layer poly(N-isopropylacrylamide) hydrogel sheet with microchannels that exhibit distinct swelling rates when subjected to stimulation. After a two-step curing process, we produce a poly(N-isopropylacrylamide)-polyethylene glycol diacrylatedouble-layer structure that can be manipulated to change its shape by controlling the light and solvent content. Based on the double-layer structure, we fabricate a dual-response driven bionic mimosa robot that can perform a variety of functions. This soft robot can not only reversibly change its shape but also maintain a specific shape without continuous stimulation. Its capacity for reversible deformation, resulting from internal stress, presents promising application prospects in the biomedical and soft robotics domain. This study delivers an insightful framework for the development of programmable soft materials.

Mechanically Ultra-Robust Fluorescent Elastomer for Elaborating Auxetic Composite.

Fluorescent elastomers are predominantly fabricated through doping fluorescent components or conjugating chromophores into polymer networks, which often involves detrimental effects on mechanical performance and also makes large-scale production difficult. Inspired by the heteroatom-rich microphase separation structures assisted by intensive hydrogen bonds in natural organisms, an ultra-robust fluorescent polyurethane elastomer is reported, which features a remarkable fracture strength of 87.2MPa with an elongation of 1797%, exceptional toughness of 678.4MJm-3 and intrinsic cyan fluorescence at 445nm. Moreover, the reversible fluorescence variation with temperature could in situ reveal the microphase separation of the elastomer in real time. By taking advantage of mechanical properties, intrinsic fluorescence and hydrogen bonds-promoted interfacial bonding ability, this fluorescent elastomer can be utilized as an auxetic skeleton for the elaboration of an integrated auxetic composite. Compared with the auxetic skeleton alone, the integrated composite shows an improved mechanical performance while maintaining auxetic deformation in a large strain below 185%, and its auxetic process can be visually detected under ultraviolet light by the fluorescence of the auxetic skeleton. The concept of introducing hydrogen-bonded heteroatom-rich microphase separation structures into polymer networks in this work provides a promising approach to developing fluorescent elastomers with exceptional mechanical properties.

Bioinspired Interfacial Friction Control: From Chemistry to Structures to Mechanics.

Organisms in nature have evolved a variety of surfaces with different tribological properties to adapt to the environment. By studying, understanding, and summarizing the friction and lubrication regulation phenomena of typical surfaces in nature, researchers have proposed various biomimetic friction regulation theories and methods to guide the development of new lubrication materials and lubrication systems. The design strategies for biomimetic friction/lubrication materials and systems mainly include the chemistry, surface structure, and mechanics. With the deepening understanding of the mechanism of biomimetic lubrication and the increasing application requirements, the design strategy of multi-strategy coupling has gradually become the center of attention for researchers. This paper focuses on the interfacial chemistry, surface structure, and surface mechanics of a single regulatory strategy and multi-strategy coupling approach. Based on the common biological friction regulation mechanism in nature, this paper reviews the research progress on biomimetic friction/lubrication materials in recent years, discusses and analyzes the single and coupled design strategies as well as their advantages and disadvantages, and describes the design concepts, working mechanisms, application prospects, and current problems of such materials. Finally, the development direction of biomimetic friction lubrication materials is prospected.

Bio-Hybrid Magnetic Robots: From Bioengineering to Targeted Therapy.

Magnetic robots possess an innate ability to navigate through hard-to-reach cavities in the human body, making them promising tools for diagnosing and treating diseases minimally invasively. Despite significant advances, the development of robots with desirable locomotion and full biocompatibility under harsh physiological conditions remains challenging, which put forward new requirements for magnetic robots' design and material synthesis. Compared to robots that are synthesized with inorganic materials, natural organisms like cells, bacteria or other microalgae exhibit ideal properties for in vivo applications, such as biocompatibility, deformability, auto-fluorescence, and self-propulsion, as well as easy for functional therapeutics engineering. In the process, these organisms can provide autonomous propulsion in biological fluids or external magnetic fields, while retaining their functionalities with integrating artificial robots, thus aiding targeted therapeutic delivery. This kind of robotics is named bio-hybrid magnetic robotics, and in this mini-review, recent progress including their design, engineering and potential for therapeutics delivery will be discussed. Additionally, the historical context and prominent examples will be introduced, and the complexities, potential pitfalls, and opportunities associated with bio-hybrid magnetic robotics will be discussed.

Minimal Bacterial Cell JCVI-syn3B as a Chassis to Investigate Interactions between Bacteria and Mammalian Cells.

Mycoplasmas are atypical bacteria with small genomes that necessitate colonization of their respective animal or plant hosts as obligate parasites, whether as pathogens, or commensals. Some can grow axenically in specialized complex media yet show only host-cell-dependent growth in cell culture, where they can survive chronically and often through interactions involving surface colonization or internalization. To develop a mycoplasma-based system to identify genes mediating such interactions, we exploited genetically tractable strains of the goat pathogen Mycoplasma mycoides (Mmc) with synthetic designer genomes representing the complete natural organism (minus virulence factors; JCVI-syn1.0) or its reduced counterpart (JCVI-syn3B) containing only those genes supporting axenic growth. By measuring growth of surviving organisms, physical association with cultured human cells (HEK-293T, HeLa), and induction of phagocytosis by human myeloid cells (dHL-60), we determined that JCVI-syn1.0 contained a set of eight genes (MMSYN1-0179 to MMSYN1-0186, dispensable for axenic growth) conferring survival, attachment, and phagocytosis phenotypes. JCVI-syn3B lacked these phenotypes, but insertion of these genes restored cell attachment and phagocytosis, although not survival. These results indicate that JCVI-syn3B may be a powerful living platform to analyze the role of specific gene sets, from any organism, on the interaction with diverse mammalian cells in culture.

Identification of a negative-strand RNA virus with natural plant and fungal hosts

The presence of viruses that spread to both plant and fungal populations in nature has posed intriguingly scientific question. We found a negative-strand RNA virus related to members of the family Phenuiviridae, named Valsa mali negative-strand RNA virus 1 (VmNSRV1), which induced strong hypovirulence and was prevalent in a population of the phytopathogenic fungus of apple Valsa canker (Valsa mali) infecting apple orchards in the Shaanxi Province of China. Intriguingly, VmNSRV1 encodes a protein with a viral cell-to-cell movement function in plant tissue. Mechanical leaf inoculation showed that VmNSRV1 could systemically infect plants. Moreover, VmNSRV1 was detected in 24 out of 139 apple trees tested in orchards in Shaanxi Province. Fungal inoculation experiments showed that VmNSRV1 could be bidirectionally transmitted between apple plants and V. mali, and VmNSRV1 infection in plants reduced the development of fungal lesions on leaves. Additionally, the nucleocapsid protein encoded by VmNSRV1 is associated with and rearranged lipid droplets in both fungal and plant cells. VmNSRV1 represents a virus that has adapted and spread to both plant and fungal hosts and shuttles between these two organisms in nature (phyto-mycovirus) and is potential to be utilized for the biocontrol method against plant fungal diseases. This finding presents further insights into the virus evolution and adaptation encompassing both plant and fungal hosts.

Green Alga-Inspired Underwater Vision Based on Light-Driven Active Ion Transport across Janus Dual-Field Heterostructures.

Natural organisms have evolved various biological ion channels to make timely responses toward different physical and/or chemical stimuli, giving guidance to construct artificial counterparts and expand the corresponding applications. They have also shown promising potential to overcome disadvantages of traditional electronic devices (e.g., energy-consuming operation and adverse humidity interference). Herein, we constructed a green alga-inspired nanofluidic system based on a Janus dual-field heterogeneous membrane (i.e., J-HM), which can function underwater as an artificial visual platform for light perception through enhanced active ion transport. The J-HM was obtained through sequentially assembled MXene and Cu-HHTP (i.e., a metal-organic framework based on the reaction between 2,3,6,7,10,11-hexahydroxytriphenylene hydrate (HHTP) and Cu2+) building units. Due to the formed temperature gradient and intramembrane electric field caused by the localized thermal excitation and efficient charge separation of J-HM under illumination, thermo-osmotic and photo-driven forces are generated for preferential cation transport from Cu-HHTP to MXene. Furthermore, unidirectional active transport can be enhanced by self-diffusion under a concentration gradient. Then, the corresponding underwater light perceptions at various light illumination conditions are explored, showing nearly a linear correlation with the light intensity. Finally, it is demonstrated that the visual platform can achieve object shape, definition, and distance recognition using a defined pixelated matrix, giving impetus to develop ionic signal transmission based sensing systems.

Photocatalytic Zinc Oxide Nanoparticles in Antibacterial Ultrafiltration Membranes for Biofouling Control.

Global water scarcity is a threat that can be alleviated through membrane filtration technologies. However, the widespread adoption of membranes faces significant challenges, primarily due to membrane biofouling. This is the reason why membrane modifications have been under increasing investigation to address the fouling issues. Antibacterial membranes, designed to combat biofouling by eliminating microorganisms, offer a promising solution. Within this study, flat sheet ultrafiltration (UF) membranes with integrated photocatalytic zinc oxide (ZnO) nanoparticles were developed, characterized, and assessed through filtration and fouling tests. The antibacterial properties of the membranes were conducted in static tests using Gram-negative bacteria-Escherichia coli-and natural tap water biofilm. The results demonstrated a notable enhancement in membrane surface wettability and fouling resistance. Furthermore, the incorporation of ZnO resulted in substantial photocatalytic antibacterial activity, inactivating over 99.9% of cultivable E. coli. The antibacterial activity persisted even in the absence of light. At the same time, the persistence of natural tap water organisms in biofilms of modified membranes necessitates further in-depth research on complex biofilm interactions with such membranes.