Compatible Solutes Research Articles

Wireless Powered Surface Acoustic Wave Platform for Achieving Integrated Functions of Fogging/Icing Protection and Monitoring.

In this study, we introduced an integrated approach using piezoelectric thin film-based surface acoustic wave (SAW) and wireless power transfer (WPT) technologies, designed for both passive monitoring and active defogging/icing functions. We systematically investigated the resonant frequency shifts of ZnO/glass SAW devices, establishing their correlations with variations in humidity and temperature under cold conditions. Acoustic waves generated through the ZnO/glass SAW device were used for defogging and deicing functions with effects of RF powers and acousto-heating thoroughly evaluated. More significantly, the WPT system was successfully applied for achieving defogging and deicing functions, with its performance comparable to that of conventional wired SAW systems. Our findings demonstrated that the WPT SAW system significantly minimizes localized acousto-heating effects, although the time taken for both defogging and deicing was slightly longer than the wired system. This work represents a significant advancement in developing multifunctional, optically compatible, and wireless-integrated solutions for SAW based ice protection.

Fabrication of optimized partial-reflection coatings for mid-infrared quantum cascade lasers

This study presents both numerical modeling and experimental fabrication of three different partial-reflection (PR) coatings each optimized for quantum cascade lasers (QCLs) that emit radiation in the mid-infrared range. A novel double-layer PR coating comprising silicon dioxide (SiO2) and silicon nitride (Si3N4) was proposed as a potential solution for compatibility with QCLs fabrication processes. Subsequently, the PR coating was compared with two well-known PR coatings: a single layer of aluminum oxide (Al2O3) and a single layer of yttrium oxide (Y2O3). The coatings were designed to reduce the reflectivity of the front laser mirror from 30% to approximately 13%. The thickness of the dielectric layers was optimized for lasers emitting at 4.4 μm, with applicability in the 2.5–6 μm range. The proposed double-layer coating achieved the desired reflectivity while reducing the total coating thickness by 120 nm. By using the presented coatings it will be possible to increase the optical power of Mid-Infrared QCLs.

Proline: A versatile amino acid in the presence of salinity and drought in the Capsicum genus

Abstract Proline (Pro) is a low-molecular-weight cyclic amino acid that plays an important role as a source of energy and reducing power and as a source of carbon and nitrogen compounds for plant development. In most plant species, Pro is considered a stress marker. It is also a common compatible solute and is used cumulatively by plants under osmotic stress. The pepper genus, which includes species of great economic importance distributed throughout the world, is the target of different types of stresses, both biotic and abiotic, and Pro plays an important role in tolerance to some of these stresses. In this work, we discuss the general aspects of the metabolism, transport, and different functions of Pro in the Capsicum genus. Special focus is given to critical investigations that should be conducted with respect to Pro accumulation under stress conditions, such as salinity and water deficit.

Multifunctional-hierarchical flexible metasurface with simultaneous low infrared emissivity, broadband microwave absorption, and dynamic visible camouflage

Sophisticated multispectral detectors have made single-band camouflage materials ineffective, consequently leading to significant advancements in metasurfaces that possess both infrared (IR), radar, and visible stealth capabilities. However, the mutual constraints of stealth principles across different bands and the demand for environment-adaptive camouflage raise challenges to existing multispectral compatible stealth solutions. Here a multifunctional-hierarchical flexible metasurface (MHFM) including an infrared suppression layer (IRSL), three microwave absorbing layers (MAL), an environmental adaptation layer (EAL), and a total reflective sheet (TRS), was designed to simultaneously achieve IR, radar, and dynamic visible stealth. Unlike the direct stacking of functional layers in existing solutions, the EAL is directly integrated with the first MAL as a part of the absorbing structure. As a proof-of-concept, an MHFM sample with an area of 300 × 300 mm2 and a minimum linewidth of 20 µm is demonstrated. The excellent multispectral camouflage performance is verified in experiments, showing low infrared emissivity (0.229, covering the wavelength of 3∼14 µm), the high absorption efficiency of over 90% in 2.53∼34.56 GHz, and dynamic camouflage in both grassland and desert environments. Our work presents a new solution for adaptive visible camouflage and competitive IR-radar stealth that is prospectively applicable in complex environments.

Biohydrogen production from saline wastewater: An overview

The escalating global demand for sustainable energy has propelled the exploration of biohydrogen production with a promising avenue for simultaneously generating clean energy and managing waste effectively. This review mainly focuses on advances in sustainable biohydrogen production from saline wastewater, especially in a process that leverages the unique abilities of halotolerant and halophilic microorganisms adapted to high-salinity conditions. It provides an extensive understanding of various biohydrogen production methods, which are biophotolysis, photofermentation, dark fermentation, and microbial electrolysis. Additionally, this review elaborated on the enzymology of hydrogen production and the impact of salt stress, with a particular emphasis on the adaptive mechanisms of “salt-in” and “compatible solute” strategies. These adaptations are crucial for maintaining enzymatic activity and structural integrity under hypertonic conditions. Through a comprehensive examination of microbial pathways and strategies, this review aimed to furnish foundational insights that will drive future research and technological innovations in biohydrogen production.

Local cryptic diversity in salinity adaptation mechanisms in the wild outcrossing Brassica fruticulosa

It is normally supposed that populations of the same species should evolve shared mechanisms of adaptation to common stressors due to evolutionary constraint. Here, we describe a system of within-species local adaptation to coastal habitats, Brassica fruticulosa, and detail surprising strategic variability in adaptive responses to high salinity. These different adaptive responses in neighboring populations are evidenced by transcriptomes, diverse physiological outputs, and distinct genomic selective landscapes. In response to high salinity Northern Catalonian populations restrict root-to-shoot Na+ transport, favoring K+ uptake. Contrastingly, Central Catalonian populations accumulate Na+ in leaves and compensate for the osmotic imbalance with compatible solutes such as proline. Despite contrasting responses, both metapopulations were salinity tolerant relative to all inland accessions. To characterize the genomic basis of these divergent adaptive strategies in an otherwise non-saline-tolerant species, we generate a long-read-based genome and population sequencing of 18 populations (nine inland, nine coastal) across the B. fruticulosa species range. Results of genomic and transcriptomic approaches support the physiological observations of distinct underlying mechanisms of adaptation to high salinity and reveal potential genetic targets of these two very recently evolved salinity adaptations. We therefore provide a model of within-species salinity adaptation and reveal cryptic variation in neighboring plant populations in the mechanisms of adaptation to an important natural stressor highly relevant to agriculture.

Microbial community response to temperature reduction during anaerobic treatment of long chain fatty acids-containing wastewater

Acclimating mesophilic biomass to low temperatures have been used to start-up psychrophilic anaerobic reactors, but limited microbial information is available during the acclimation. To investigate microbial responses to temperature reductions, duplicate lab-scale anaerobic digestion (AD) reactors were operated for 166 days, with the temperature being reduced from 37°C to 15°C, using synthetic long chain fatty acid (LCFA)-containing wastewater as the feedstock. The acclimated biomass at 15°C exhibited efficient removal of organic matter (total COD>75%, soluble COD>88%, and LCFA>99%). Temperature reductions lead to significant reductions in microbiome diversity. Fermentative bacteria were highly dynamic and functional redundant during temperature reductions. Smithella was the dominant syntrophic bacteria involved in LCFA degradation coupled with Methanothrix and Methanocorpusculum at 15°C. Membrane modifications and compatible cellular solutes production were triggered by temperature reductions as microbial response to cold stress. This study provided molecular insights in microbial acclimation to low temperatures for psychrophilic AD.

Improving grapevine (Vitis vinifera L., cv. Superior Seedless) drought tolerance with cerium oxide nanoparticles: Agronomic and molecular insights

Drought stress poses a significant threat to global food security, impacting grapevine growth and development through physiological, biochemical, and molecular alterations. Cerium oxide nanoparticles (CeO2 NPs) have recently gained attention as a potential solution to environmental challenges, yet their application in grapevines remains understudied. This study examined the interaction between foliar-applied CeO2 NPs (at concentrations of 0, 5, 50, and 500 mg L−1) and drought stress (at 30% and 70% of field capacity humidity) in grapevine saplings. Among the different concentrations tested, 50 mg L−1 CeO2 NPs significantly improved the agronomic traits (e.g., shoot length, leaf area, shoot and root dry weights), photosynthetic parameters (stomatal conductance, chlorophyll a and chlorophyll b) and RWC of the grapevine saplings under drought stress. In parallel, CeO2 NPs significantly induced the activity of compatible solutes and SOD, CAT and APX under drought stress conditions. Moreover, the availability of CeO2 NPs alleviated drought stress-induced damage in grapevine saplings, as evidenced by decreased H2O2 (32.63%), EL (40.35%) and MDA (50.63%) levels. The molecular results revealed that CeO2 NPs caused significant changes in gene expression under drought stress by reducing the expression of the VvCLH1, VvCu/ZnSOD, VvRD29A and VvRBOHA genes by 4.54-fold, 27.73-fold, 14.6-fold and 46.12-fold, respectively. These findings suggest that CeO2 NPs applied via leaves enhance grapevine sapling resistance to drought-induced oxidative stress through cooperative enzymatic and nonenzymatic antioxidant mechanisms, influencing gene regulation. As a result, these findings revealed that CeO2 NPs could be promising elicitor candidates for alleviating drought stress in grapevines.

Acidic proteomes are linked to microbial alkaline preference in African lakes

Microbial amino acid composition (AA) reflects adaptive strategies of cellular and molecular regulations such as a high proportion of acidic AAs, including glutamic and aspartic acids in alkaliphiles. It remains understudied how microbial AA content is linked to their pH adaptation especially in natural environments. Here we examined prokaryotic communities and their AA composition of genes with metagenomics for 39 water and sediments of East African lakes along a gradient of pH spanning from 7.2 to 10.1. We found that Shannon diversity declined with the increasing pH and that species abundance were either positively or negatively associated with pH, indicating their distinct habitat preference in lakes. Microbial communities showed higher acidic proteomes in alkaline than neutral lakes. Species acidic proteomes were also positively correlated with their pH preference, which was consistent across major bacterial lineages. These results suggest selective pressure associated with high pH likely shape microbial amino acid composition both at the species and community levels. Comparative genome analyses further revealed that alkaliphilic microbes contained more functional genes with higher acidic AAs when compared to those in neutral conditions. These traits included genes encoding diverse classes of cation transmembrane transporters, antiporters, and compatible solute transporters, which are involved in cytoplasmic pH homeostasis and osmotic stress defense under high pH conditions. Our results provide the field evidence for the strong relationship between prokaryotic AA composition and their habitat preference and highlight amino acid optimization as strategies for environmental adaptation.

Assessment of the impact of fuelling puff location on divertor impurity compression and enrichment in STEP

In order to achieve a compatible solution between the divertors and the core, SOLPS-ITER simulations were performed in a Spherical Tokamak for Energy Production (STEP) connected double-null geometry to investigate the possibility of using deuterium ( D2 ) puff locations as an actuator for divertor argon (Ar) compression/enrichment. It was found that puffing D2 from the inner-midplane (IMP) D2 puff enhanced Ar compression and enrichment on the high-field-side (HFS) and lowered the required upstream Ar fraction to achieve acceptable target conditions. An interesting link was found between argon compression and the number of stagnation points of the middle-charge-state Ar ions in the HFS SOL, Nst ; significantly improved compression and enrichment were obtained for Nst=1 (corresponding mostly to the cases with IMP puff) compared to Nst=3 (corresponding mostly to the cases without IMP puff). An intermediate compression and enrichment was obtained when Nst=5 . The change of Nst from 3 to 1 (or 5) was achieved by a combination of D+ outflow, high collision frequency, and flipped temperature gradients around the IMP. Given a possible drawback of ΓDOMP+IMP , that is a direct effect on the upstream main plasma density and temperature, we propose ΓDPFR+IMP as the best solution, balancing the negative and positive effects of private-flux-region and IMP D2 puffs. Further studies will be carried out both experimentally and numerically.

Metagenomic insights into the prokaryotic communities of heavy metal-contaminated hypersaline soils

Saline soils and their microbial communities have recently been studied in response to ongoing desertification of agricultural soils caused by anthropogenic impacts and climate change. Here we describe the prokaryotic microbiota of hypersaline soils in the Odiel Saltmarshes Natural Area of Southwest Spain. This region has been strongly affected by mining and industrial activity and feature high levels of certain heavy metals. We sequenced 18 shotgun metagenomes through Illumina NovaSeq from samples obtained from three different areas in 2020 and 2021. Taxogenomic analyses demonstrate that these soils harbored equal proportions of archaea and bacteria, with Methanobacteriota, Pseudomonadota, Bacteroidota, Gemmatimonadota, and Balneolota as most abundant phyla. Functions related to the transport of heavy metal outside the cytoplasm are among the most relevant features of the community (i.e., ZntA and CopA enzymes). They seem to be indispensable to avoid the increase of zinc and copper concentration inside the cell. Besides, the archaeal phylum Methanobacteriota is the main arsenic detoxifier within the microbiota although arsenic related genes are widely distributed in the community. Regarding the osmoregulation strategies, “salt-out” mechanism was identified in part of the bacterial population, whereas “salt-in” mechanism was present in both domains, Bacteria and Archaea. De novo biosynthesis of two of the most universal compatible solutes was detected, with predominance of glycine betaine biosynthesis (betAB genes) over ectoine (ectABC genes). Furthermore, doeABCD gene cluster related to the use of ectoine as carbon and energy source was solely identified in Pseudomonadota and Methanobacteriota.

Salt-Tolerant Plant Growth-Promoting Bacteria (ST-PGPB): An Effective Strategy for Sustainable Food Production.

Soil is the backbone of the agricultural economy of any country. Soil salinity refers to the higher concentration of soluble salts in the soil. Soil salinity is a ruinous abiotic stress that has emerged as a threatening issue for food security. High salt concentration causes an ionic imbalance that hampers water uptake, affecting photosynthesis and other metabolic processes, ultimately resulting in inferior seed germination and stunted plant growth. A wide range of strategies have been adopted to mitigate the harmful effects of salinity such as efficient irrigation techniques, soil reclamation, habitat restoration, flushing, leaching or using salt-tolerant crops, but all the methods have one or more limitations. An alternative and effective strategy is the exploitation of salt-tolerant plant growth-promoting bacteria (ST-PGPB) to mitigate salt stress and improve crop productivity. ST-PGPB can survive in salinity-tainted environments and perform their inherent plant growth-promoting and biocontrol functions effectively. Additionally, ST-PGPB can rescue plants via stress-responsive mechanisms including production of growth regulators, maintenance of osmotic balance, aminocyclopropane-1-carboxylate (ACC) deaminase activity, exopolysaccharides (EPS) activity, improvement in photosynthesis activity, synthesis of compatible solutes, antioxidant activity and regulation of salt overly sensitive (SOS) signaling pathway. Several well-known ST-PGPB, specifically Azospirillum, Bacillus, Burkholderia, Enterobacter, Pseudomonas and Pantoea, are used as bioinoculants to improve the growth of different crops. The application of ST-PGPB allows plants to cope with salt stress by boosting their defense mechanisms. This review highlights the impact of salinity stress on plant growth and the potential of ST-PGPB as a biofertilizer to improve crop productivity under salt stress.

Photothermal ZrN composite membranes for solar-driven water distillation

Many regions around the world, including the Arabian Peninsula, face a scarcity of freshwater resources and depend heavily on non-renewable energy sources for energy-intensive desalination processes, emphasizing the need for sustainable water treatment methods. To tackle this challenge, solar energy-driven membrane distillation is a promising and compatible solution for desalinating seawater. In this work, a solar-powered photothermal air gap membrane distillation (AGMD) system has been tested to treat brine by utilizing plasmonic-based composite membranes. Polyvinylidene fluoride (PVDF) membranes were prepared by incorporating low-cost zirconium nitride (ZrN) nanoparticles at varying concentrations to facilitate solar energy harvesting. ZrN-modified PVDF composite membranes significantly boost the solar absorption up to 75 % in the wavelength range of 250–800 nm, when compared to pristine PVDF membranes. The composite membranes with 56 % enhancement in porosity resulted in a permeate flux of 0.36 L m−2 h−1 and a rejection rate of ∼99 %. The developed photothermal water treatment system provides a highly effective and scalable solution for water treatment. Moreover, next-generation materials exhibiting photothermal effects have the potential to exploit solar renewable energy for decentralized off-grid desalination by converting sunlight into heat for a unique and favourable water-energy nexus.

Plant Adaptation and Tolerance to Heat Stress: Advance Approaches and Future Aspects.

Heat stress impacts plant growth at all phases of development, although the particular threshold for heat tolerance varies significantly across different developmental stages. During seed germination, elevated temperatures can either impede or completely halt the process, contingent upon the plant type and the severity of the stress. During advanced stages, high temperatures can have a negative impact on photosynthesis, respiration, water balance, and membrane integrity. Additionally, they can also influence the levels of hormones and primary and secondary metabolites. In addition, during the growth and development of plants, there is an increased expression of various heat shock proteins, as well as other proteins related to stress, and the generation of reactive oxygen species (ROS). These are significant plant responses to heat stress. Plants employ several strategies to deal with heat stress, such as maintaining the stability of their cell membranes, removing harmful reactive oxygen species (ROS), producing antioxidants, accumulating and adjusting compatible solutes, activating mitogen-activated protein kinase (MAPK) and calcium-dependent protein kinase (CDPK) cascades, and, crucially, signaling through chaperones and activating transcription. These molecular-level systems boost the ability of plants to flourish in heat stress. Potential genetic methods to enhance plant heat stress resistance encompass old and modern molecular breeding techniques and transgenic approaches, all of which rely on a comprehensive comprehension of these systems. Although several plants exhibit enhanced heat tolerance through traditional breeding methods, the effectiveness of genetic transformation techniques has been somewhat restricted. The latter results from the current constraints in our understanding and access to genes that have known impacts on plant heat stress tolerance. However, these challenges may be overcome in the future. Besides genetic methods, crops' heat tolerance can be improved through the pre-treatment of plants with various environmental challenges or the external application of osmoprotectants such as glycine betaine and proline. Thermotolerance is achieved through an active process in which plants allocate significant energy to maintain their structure and function to avoid damage induced by heat stress. The practice of nanoparticles has been shown to upgrade both the standard and the quantity of produce when crops are under heat stress. This review provides information on the effects of heat stress on plants and explores the importance of nanoparticles, transgenics, and genomic techniques in reducing the negative consequences of heat stress. Furthermore, it explores how plants might adapt to heat stress by modifying their biochemical, physiological, and molecular reactions.

Osmotic stress response of the coral and oyster pathogen Vibrio coralliilyticus: acquisition of catabolism gene clusters for the compatible solute and signaling molecule myo-inositol.

Marine bacteria experience fluctuations in osmolarity that they must adapt to, and most bacteria respond to high osmolarity by accumulating compatible solutes also known as osmolytes. The osmotic stress response and compatible solutes used by the coral and oyster pathogen Vibrio coralliilyticus were unknown. In this study, we showed that to alleviate osmotic stress V. coralliilyticus biosynthesized glycine betaine (GB) and transported into the cell choline, GB, ectoine, dimethylglycine, and dimethylsulfoniopropionate, but not myo-inositol. Myo-inositol is a stress protectant and a signaling molecule that is biosynthesized and used by algae. Bioinformatics identified myo-inositol (iol) catabolism clusters in V. coralliilyticus and other Vibrio, Photobacterium, Grimontia, and Enterovibrio species. Growth pattern analysis demonstrated that V. coralliilyticus utilized myo-inositol as a sole carbon source, with a short lag time of 3 h. An iolG deletion mutant, which encodes an inositol dehydrogenase, was unable to grow on myo-inositol. Within the iol clusters were an MFS-type (iolT1) and an ABC-type (iolXYZ) transporter and analyses showed that both transported myo-inositol. IolG and IolA phylogeny among Vibrionaceae species showed different evolutionary histories indicating multiple acquisition events. Outside of Vibrionaceae, IolG was most closely related to IolG from a small group of Aeromonas fish and human pathogens and Providencia species. However, IolG from hypervirulent A. hydrophila strains clustered with IolG from Enterobacter, and divergently from Pectobacterium, Brenneria, and Dickeya plant pathogens. The iol cluster was also present within Aliiroseovarius, Burkholderia, Endozoicomonas, Halomonas, Labrenzia, Marinomonas, Marinobacterium, Cobetia, Pantoea, and Pseudomonas, of which many species were associated with marine flora and fauna.IMPORTANCEHost associated bacteria such as Vibrio coralliilyticus encounter competition for nutrients and have evolved metabolic strategies to better compete for food. Emerging studies show that myo-inositol is exchanged in the coral-algae symbiosis, is likely involved in signaling, but is also an osmolyte in algae. The bacterial consumption of myo-inositol could contribute to a breakdown of the coral-algae symbiosis during thermal stress or disrupt the coral microbiome. Phylogenetic analyses showed that the evolutionary history of myo-inositol metabolism is complex, acquired multiple times in Vibrio, but acquired once in many bacterial plant pathogens. Further analysis also showed that a conserved iol cluster is prevalent among many marine species (commensals, mutualists, and pathogens) associated with marine flora and fauna, algae, sponges, corals, molluscs, crustaceans, and fish.

Extremozymes and compatible solute production potential of halophilic and halotolerant bacteria isolated from crop rhizospheric soils of Southwest Saurashtra Gujarat

Halophiles are one of the classes of extremophilic microorganisms that can flourish in environments with very high salt concentrations. In this study, fifteen bacterial strains isolated from various crop rhizospheric soils of agricultural fields along the Southwest coastline of Saurashtra, Gujarat, and identified by 16S rRNA gene sequencing as Halomonas pacifica, H. stenophila, H. salifodinae, H. binhaiensis, Oceanobacillus oncorhynchi, and Bacillus paralicheniformis were investigated for their potentiality to produce extremozymes and compatible solute. The isolates showed the production of halophilic protease, cellulase, and chitinase enzymes ranging from 6.90 to 35.38, 0.004–0.042, and 0.097–0.550 U ml−1, respectively. The production of ectoine-compatible solute ranged from 0.01 to 3.17 mg l−1. Furthermore, the investigation of the ectoine-compatible solute production at the molecular level by PCR showed the presence of the ectoine synthase gene responsible for its biosynthesis in the isolates. Besides, it also showed the presence of glycine betaine biosynthetic gene betaine aldehyde dehydrogenase in the isolates. The compatible solute production by these isolates may be linked to their ability to produce extremozymes under saline conditions, which could protect them from salt-induced denaturation, potentially enhancing their stability and activity. This correlation warrants further investigation.

Genome Sequence Resource of Bacillus mojavensis KRS009, a Rhizospheric Microorganism with Biocontrol Potential

Bacillus mojavensis KRS009 was identified as an antagonistic strain with a strong inhibitory effect on various phytopathogenic fungi. To provide further insight into its biocontrol mechanisms and ability to improve plant salt tolerance, the high quality complete genome of KRS009 was sequenced by PacBio platform and assembled using PacBio-HiFiReads. The KRS009 genome consists of one circular chromosome of 4,089,687 bp with 43.5% GC content and 4,062 open reading frames, of which 3,920 protein-coding genes, 86 transfer RNA, 10 ribosomal RNA, and 26 small RNA were identified in this genome. Among them, genes related to compatible solutes, including treC, galU, proX, and proW, are involved in the synthesis of trehalose, proline, and betaine metabolism and play an important role in relieving osmotic stress. In addition, the KRS009 genome contains genes associated with high salinity tolerance, including those responsible for Na+/H+ antiporters, K+ transporters, TrkH thiamin phosphate synthase, K+-sensing histidine kinase, aryl-phospho-beta-D-glucosidase, flavoprotein CzcO associated with the cation diffusion facilitator CzcD, and chaperonin GroEL. Together, the high-quality genome resource of strain KRS009 would provide a molecular basis for further research on its biocontrol and plant salt tolerance mechanisms. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

The ameliorating effects of cinnamic acid-based nanocomposite against salt stress in peppermint.

Nanoparticles (NPs) are important in regulating plant tolerance to salt stress. Peppermint is one of the most widely used aromatic plants, with a high sensitivity to salt stress. The present study investigated physiological and biochemical factors to understand better the behavior of cinnamic acid (CA) and cinnamic acid nanocomposite in salinity control in peppermint plants. The first factor was salt stress with different salt concentrations, including 0, 50, 100, and 150 mg/L, the second factor was 50 μM CA, and the third factor was 50 μM CA nanocomposite based on carboxymethyl cellulose (CMC-CA NC). Results showed that stress markers increased with increasing salinity levels. On the contrary, plants treated with salinity showed a decrease in physiological and photosynthetic parameters, while the application of CA and CMC CA NC increased these critical parameters. Under salinity, compared to the control, malondialdehyde and hydrogen peroxide contents decreased by 11.3% and 70.4%, respectively. Furthermore, CA and CMC-CA NC enhanced peppermint tolerance to salinity by increasing compatible solute content such as proline, free amino acids, protein content, and soluble carbohydrates, increasing antioxidant enzymes, and decreasing stress markers in plant tissues. Compared to the control, chlorophyll fluorescence and proline content increased by 1.1% and 172.1%, respectively. Salinity stress negatively affected all physiological and biochemical parameters, but CA and CMC-CA NC treatments improved them. We concluded that the nanocomposite, a biostimulant, significantly enhances mint tolerance under salinity conditions.

A (2 + 1)-Dimensional Integrable Breaking Soliton Equation and Its Algebro-Geometric Solutions+

A new (2 + 1)-dimensional breaking soliton equation with the help of the nonisospectral Lax pair is presented. It is shown that the compatible solutions of the first two nontrivial equations in the (1 + 1)-dimensional Kaup–Newell soliton hierarchy provide solutions of the new breaking soliton equation. Then, the new breaking soliton equation is decomposed into the systems of solvable ordinary differential equations. Finally, a hyperelliptic Riemann surface and Abel–Jacobi coordinates are introduced to straighten the associated flow, from which the algebro-geometric solutions of the new (2 + 1)-dimensional integrable equation are constructed by means of the Riemann θ functions.

Stochastic Character Mapping, Bayesian Model Selection, and Biosynthetic Pathways Shed New Light on the Evolution of Habitat Preference in Cyanobacteria.

Cyanobacteria are the only prokaryotes to have evolved oxygenic photosynthesis paving the way for complex life. Studying the evolution and ecological niche of cyanobacteria and their ancestors is crucial for understanding the intricate dynamics of biosphere evolution. These organisms frequently deal with environmental stressors such as salinity and drought, and they employ compatible solutes as a mechanism to cope with these challenges. Compatible solutes are small molecules that help maintain cellular osmotic balance in high salinity environments, such as marine waters. Their production plays a crucial role in salt tolerance, which, in turn, influences habitat preference. Among the five known compatible solutes produced by cyanobacteria (sucrose, trehalose, glucosylglycerol, glucosylglycerate, and glycine betaine), their synthesis varies between individual strains. In this study, we work in a Bayesian stochastic mapping framework, integrating multiple sources of information about compatible solute biosynthesis in order to predict the ancestral habitat preference of Cyanobacteria. Through extensive model selection analyses and statistical tests for correlation, we identify glucosylglycerol and glucosylglycerate as the most significantly correlated with habitat preference, while trehalose exhibits the weakest correlation. Additionally, glucosylglycerol, glucosylglycerate, and glycine betaine show high loss/gain rate ratios, indicating their potential role in adaptability, while sucrose and trehalose are less likely to be lost due to their additional cellular functions. Contrary to previous findings, our analyses predict that the last common ancestor of Cyanobacteria (living at around 3180 Ma) had a 97% probability of a high salinity habitat preference and was likely able to synthesise glucosylglycerol and glucosylglycerate. Nevertheless, cyanobacteria likely colonized low-salinity environments shortly after their origin, with an 89% probability of the first cyanobacterium with low-salinity habitat preference arising prior to the Great Oxygenation Event (2460 Ma). Stochastic mapping analyses provide evidence of cyanobacteria inhabiting early marine habitats, aiding in the interpretation of the geological record. Our age estimate of ~2590 Ma for the divergence of two major cyanobacterial clades (Macro- and Microcyanobacteria) suggests that these were likely significant contributors to primary productivity in marine habitats in the lead-up to the Great Oxygenation Event, and thus played a pivotal role in triggering the sudden increase in atmospheric oxygen.