Properties Of Different Species Research Articles

Benefits of Mushroom-Based Supplements on Growth Performance, Immunocompetence, and Meat Quality in Poultry.

The restriction on the use of antibiotics in poultry has led to an increase in the use of natural products that could serve as alternatives to antibiotics. Mushrooms contain bioactive compounds that exhibit antifungal, antiparasitic, antibacterial, antioxidant, antiviral, anti-inflammatory, and cytotoxic properties. Hence, they are being tested, revealing as performance-enhancing natural feed additives for livestock. This review focused on the role of different species of mushrooms commonly used in poultry on the performance, immunomodulatory actions, cholesterolemic properties, and meat quality of poultry birds. Different studies reviewed show that mushrooms could positively impact poultry production, improve growth performance, modulate immune response, exert tissue antioxidant activity, influence intestinal morphology, enhance gut microbiome, and improve lipid profile. The variations in their efficacy could be attributed to the variations in physicochemical properties of different species and dosage levels applied in the experiments. However, the use of mushrooms as a natural product supplement is in its infancy, and more basic, pilot and large-scale research is required to make it a viable approach for improving immune responses in the poultry industry.

Abstract 7602: Discovery of GH1581, a potent and selective WRN inhibitor as a cancer therapy

Abstract Defects in DNA mismatch repair (MMR) proteins could induce damage of genome, resulting microsatellite instability (MSI). MSI is highly correlated with the occurrence of several types of cancers, mainly in colon, gastric, endometrial, and ovarian cancers. Despite advances in the treatment of MSI-high cancers, tumor evolution and drug resistance remain the leading causes of treatment failure and death in cancer patients. About 50% MSI cancers have no response to immune checkpoint inhibitors. There is still unmet needs to be fulfilled for MSI-high patients. WRN is a RecQ family helicase involves in genome stability maintenance, DNA repair, replication, transcription, and telomere maintenance. Recent studies have identified WRN as a synthetic lethal target of MSI-high cancers. Employing structure-based drug design strategy, we have discovered a potent and selective WRN inhibitor, GH1581. In vitro, GH1581 displayed specific < 10 nM potency in ADP-Glo assay and < 10 nM potency in cell proliferation assay using MSI cancer cell lines. In vivo, GH1581 demonstrated favorable pharmacokinetic properties in different species. In SW48 xenograft model, it inhibited the tumor growth with 100% TGI at QD dosing of 10 mg/kg without severe adverse effect on body weight. In summary, we discovered GH1581 as a novel inhibitor of WRN with high in vitro and in vivo efficacy. Citation Format: Jiapeng Li, Guiping Zhang, Jie Jack Li. Discovery of GH1581, a potent and selective WRN inhibitor as a cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7602.

Discovery and Preclinical Study of Novel BTK Degrader HZ-Q1060

Introduction: Bruton's tyrosine kinase （BTK） is a clinical validated drug target for therapy of B cell lymphoma and autoimmune diseases. However, same as other kinase inhibitors, acquired drug resistance, which is the result of BTK C481S mutation, has been observed in patients. So reversible BTK inhibitors were developed to overcome acquired drug resistance of covalent BTK inhibitor. While, in order to have enough efficacy, reversible BTK inhibitors required much higher drug exposure which may lead to higher risk of adverse effect. Hence, it is urgent to develop new technique to overcome drug resistance caused by BTK C481S mutation. Proteolysis-targeting chimeras(PROTAC) is promising new strategy for drug development. PROTAC can achieve sustained target degradation in a catalytical mechanism. So comparing with traditional small molecule inhibitor, PROTAC drug has great advantage in solving acquired drug resistance. Therefore, with the aim of solving acquired drug resistance of 1st generation of BTK inhibitor, we identified a novel BTK-PROTAC HZ-Q1060 based on our in-house DaTProD® platform which is setting up to promote PROTAC development. After a series of evaluations, HZ-Q1060 has been validated as a promising pre-clinical candidate for further clinical development. Results:HZ-Q1060 can effectively degrade BTK in cancer cell lines and human PBMC, and the half degradation concentration (DC50) in Mino is less than 0.5nM. At the same time, HZ-Q1060 can also induce the degradation of intracellular mutant BTK-C481S protein.HZ-Q1060 has not observed any inhibition and degradation effect on other kinases except BTK, especially kinases that may be related to potential side effects by inhibiting, such as EGFR and TEC.In vitro cancer cell growth inhibition assay, it completely suppressed the cell proliferation of a panel of lymphoma cell lines such as Mino(IC50=0.11nM) and OCI-ly10(IC50=0.28nM).In the PK/PD experiment in mice, a single oral administration of medium dose can degrade more than 80% of BTK within 6 hours, and the degradation effect can be maintained until 24 hours after administration.In the subcutaneous transplanted tumor model of OCI-ly10 mice, the tumor growth was completely inhibited by 3mg/kg of HZ-Q1060 administered orally every day for 14 days, which was equivalent to that of ibrutinib 10mg/kg.In the preclinical pharmacokinetic studies, HZ-Q1060 showed excellent pharmacokinetic properties in different species of animals, included mice, rats and beagle dogs, with long T1/2 and high dose-normalized AUC.HZ-Q1060 has no significant CYPs inhibitory effect at 10 μM, so it has a low risk of DDI in the future combination therapy.HZ-Q1060 has no inhibitory effect on hERG channel, indicating the compound has a low potential to induce QT prolongation. HZ-Q1060 also shows good safety and tolerance in the preliminary safety evaluation of animals. Conclusion: In summary, HZ-Q1060 is a potent and selective degrader of BTK with good ADME properties and in vivo efficacy, which makes it suitable for further evaluation in clinical development.

Genome-wide annotation of cuticular protein genes in non-biting midge Propsilocerus akamusi and transcriptome analysis of their response to heavy metal pollution

The insect cuticle is a sophisticated chitin-protein extracellular structure for mutable functions. The cuticles varied their structures and properties in different species, and the same species but in different regions or at different stages, to fill the requirements of different functions. The alteration of cuticle structures may also be induced due to challenges by some environmental crises, such as pollution exposures. The physical properties of the cuticle were determined by the cuticle proteins (CPs) they contain. The cuticle proteins are large protein groups in all insects, which are commonly divided into different families according to their conserved protein sequence motifs. Although Chironomidae is an abundant and universal insect in global aquatic ecosystems and a popular model for aquatic toxicology, no systematic annotation of CPs was done for any species in Chironomidae before. In this work, we annotated the CP genes of Propsilocerus akamusi, the most abundant Chironomidae species in Asia. A total of 160 CP genes were identified, and 97 of them could be well classified into eight CP families: 76 CPR genes can be subdivided into three groups (further divided into three subgroups: 36 RR1 genes, 37 RR2 genes, and 3 RR3 genes), 2 CPF genes, 3 CPLCA genes, 1 CPLCG gene, 8 CPAP genes, and 3 Tweedle genes. Additionally, we analyzed the response of P. akamusi CP genes at expression level to Cu exposure, which is related to the high heavy metal tolerance and the earlier onset of pupariation in heavy metal polluted water.

Biochemical properties of different species of seaweeds (Grateloupia) from the Indian coast and analysis of spatial variation in two selected species

Aim: The present study aimed to investigate the biochemical composition of five Grateloupia species and analysis of spatial variation in G. filicina and G. lithophila from the East and West coast of India. Methodology: Five Grateloupia species such as G. filicina, G. lithophila, G. catenata, G. orientalis and G. indica were collected from different states of India. Biochemical parameters like crude protein, total lipid, total ash, carbohydrates, total dietary fibre, chlorophyll, carotenoids, and total phenolic content were estimated to assess their nutritional values. Spatial variation for same parameters was also studied for G. filicina and G. lithophila. Results: It was observed that genus Grateloupia contained crude protein (12.4-16%), total lipid (0.61-1.47%), ash (11.49-18.03%), carbohydrate (5.17-17.21%), and total dietary fibre (54.08-66.16%) on a dry weight basis. Among all species, G. indica (16.00%) and G. filicina (15.48%) consisted of higher protein content. In contrast, G. orientalis (66.16%) and G. catenata (61.25%) had a maximum of total dietary fibre. The digestible energy obtained from Grateloupia was high, ranging from 85.93-141.29 kcal. Carotenoids (9.52-32.10 mg 100g-1) and total phenolic contents (TPC) (0.508-0.696 mg GAE g-1) represented the potential antioxidant activities of these Grateloupia species. Spatial variation in the biochemical composition of G. filicina and G. lithophila may be due to changes in the environmental factors. Interpretation: Biochemical compositions of these five species were similar to other edible Grateloupia species like G. turuturu and G. filicina. The results revealed that these species could be used for consumption purposes. Key words: Fibre, Grateloupia, Nutritional property, Phenols, Species, Spatial variation

Discovery of IHMT-MST1-58 as a Novel, Potent, and Selective MST1 Inhibitor for the Treatment of Type 1/2 Diabetes.

The critical pathogenesis of type 1 diabetes (T1D)/type 2 diabetes (T2D) is the physical status, mass, and function of pancreatic β cells. Mammalian STE20-like protein 1 kinase (MST1) plays vital roles in the apoptosis and insulin secretion of β cells. Here, we discovered a novel, potent, and selective MST1 inhibitor 19 (IC50 = 23 nM), which inhibited the phosphorylation of MST1-protected β cells from the damage of inflammatory cytokines in vitro. In vivo, it displayed acceptable pharmacokinetic properties in different species. In the STZ-induced T1D/T2D mouse models, both monotherapy of 19 and in combination with metformin led to the decline of fasting blood glucose and showed protective effect of β cells. In addition, the combination of 19 and metformin decreased the hemoglobin A1c level. Together, our study suggested that 19 might be a useful pharmacological tool to study MST1-mediated physiology and pathology as well as a potential drug candidate for diabetes.

Edible Mushrooms Could Take Advantage of the Growth-Promoting and Biocontrol Potential of Azospirillum

Abstract Investigations of biologically active substances sourced from xylotrophic macromycetes have shown their fundamental and practical significance. These studies have promoted the development of biotechnologies by obtaining the valuable products from the mycelial biomass and cultivation liquid and using these fungal species in “white chemistry”. Research into environmentally safe biological methods of stimulating the growth of medicinal and edible mushrooms can assist the development of scientific foundations of culture technologies. From the viewpoint of their bio-technological potential, selected factors of biological origin that promote the growth of wide-scale cultivated basidiomycetes are of interest. Improving mushroom resistance against negative environmental impacts seems to be feasible when the mushroom grows in combination with growth-promoting bacteria. The soil bacteria from the Azospirillum genus have attracted attention, as microorganisms are capable of actively influencing the growth and development of agricultural crops. Thus, revealing and exploring the growth-promoting properties of different species of Azospirillum with respect to edible and/or medicinal mushrooms, as well as the properties promoting the suppression of contaminants in double culture, are believed to be feasible and to reveal undoubted novelty. Cultivation jointly with the beneficial bacteria is a more effective biotechnological method for obtaining this valuable functional food faster, with a greater and much better and maintained mushroom yield. Future work involves addressing the problems of mushroom growth promoting bacterial interactions with mushrooms and implementing these synthetic microbial associations into agriculture.

Pós-colheita de flores comestíveis

Abstract The objective of this work was to evaluate the changes in the physicochemical properties of different species of edible flowers in the postharvest period. Flowers of Viola cornuta (light or dark colored), Viola tricolor, Antirrhinum majus, Dianthus chinensis, and Tagetes patula were selected, packed, and placed in a cold chamber of the BOD type, at 5±1°C and 90–95% relative humidity. Every two days, fresh weight loss, visual quality using a scale score, and total longevity were evaluated. The total soluble solids (SS) content, titratable acidity (TA), the SS/TA ratio, and pH were also evaluated at the time of harvest and at the end of postharvest life. There was a significant increase in the SS contents of light-colored V. cornuta, V. tricolor, and D. chinensis. A significant reduction in TA was observed in light-colored V. cornuta, V. tricolor, A. majus, and D. chinensis at the end of postharvest life. The pH value increased significantly only in T. patula flowers. The studied species of edible flowers have a short commercial longevity, which varies from 4 to 10 days, while the maximum total longevity varies from 6 to 14 days.

Mechanical defensive adaptations of three Mediterranean sea urchin species.

In the Mediterranean, Paracentrotus lividus and Sphaerechinus granularis are important drivers of benthic ecosystems, often coexisting in sublittoral communities. However, the introduction of the invasive diadematoid Diadema setosum, which utilizes venomous spines, may affect these communities. To describe the mechanical properties of the test and spines of these three species, specimens were collected in winter of 2019 from the sublittoral zone of the Dodecanese island complex, southeastern Aegean Sea. This region serves as a gateway for invasive species to the Mediterranean Sea. Crushing test was conducted on live individuals, while 3‐point bending test was used to estimate spine stiffness. Porosity and mineralogy of the test and spine, thickness of the test, and breaking length of the spine were measured and compared, while the microstructural architecture was also determined. The test of S. granularis was the most robust (194.35 ± 59.59 N), while the spines of D. setosum (4.76 ± 2.13 GPa) exhibited highest flexibility. Increased porosity and thickness of the test were related to increased robustness, whereas increased flexibility of the spine was attributed to high porosity, indicating that porosity in the skeleton plays a key role in preventing fracture. The spines of S. granularis exhibited highest length after fracture % (71.54 ± 5.5%). D. setosum exhibited higher values of Mg concentration in the test (10%) compared with the spines (4%). For the first time, the mineralogy of an invasive species is compared with its native counterpart, while a comparison of the mechanical properties of different species of the same ecosystem also takes place. This study highlights different ways, in which sea urchins utilize their skeleton and showcases the ecological significance of these adaptations, one of which is the different ways of utilization of the skeleton for defensive purposes, while the other is the ability of D. setosum to decrease the Mg % of its skeleton degrading its mechanical properties, without compromising its defense, by depending on venomous bearing spines. This enables this species to occupy not only tropical habitats, where it is indigenous, but also temperate like the eastern Mediterranean, which it has recently invaded.

Histology and transcriptomic analyses of barnacles with different base materials and habitats shed lights on the duplication and chemical diversification of barnacle cement proteins

BackgroundBarnacles are sessile crustaceans that attach to underwater surfaces using barnacle cement proteins. Barnacles have a calcareous or chitinous membranous base, and their substratum varies from biotic (e.g. corals/sponges) to abiotic surfaces. In this study, we tested the hypothesis that the cement protein (CP) composition and chemical properties of different species vary according to the attachment substrate and/or the basal structure. We examined the histological structure of cement glands and explored the variations in cement protein homologs of 12 barnacle species with different attachment habitats and base materials.ResultsCement gland cells in the rocky shore barnacles Tetraclita japonica formosana and Amphibalanus amphitrite are eosinophilic, while others are basophilic. Transcriptome analyses recovered CP homologs from all species except the scleractinian coral barnacle Galkinia sp. A phylogenomic analysis based on sequences of CP homologs did not reflect a clear phylogenetic pattern in attachment substrates. In some species, certain CPs have a remarkable number of paralogous sequences, suggesting that major duplication events occurred in CP genes. The examined CPs across taxa show consistent bias toward particular sets of amino acid. However, the predicted isoelectric point (pI) and hydropathy are highly divergent. In some species, conserved regions are highly repetitive.ConclusionsInstead of developing specific cement proteins for different attachment substrata, barnacles attached to different substrata rely on a highly duplicated cementation genetic toolkit to generate paralogous CP sequences with diverse chemical and biochemical properties. This general CP cocktail might be the key genetic feature enabling barnacles to adapt to a wide variety of substrata.

Deciphering of Candida parapsilosis induced immune response in Drosophila melanogaster

ABSTRACT Candida infections are the most prevalent cause of serious human mycoses and are the third most common pathogens isolated from bloodstream infections in hospitalized patients. C. parapsilosis is a member of the non-albicans spp., which have a predilection for causing life-threatening disease in neonates and hospitalized pediatric patients. In this study, we utilized a Drosophila melanogaster infection model to analyze the immunological responses to C. parapsilosis. Our results demonstrate that the Toll pathway in Drosophila controls C. parapsilosis proliferation as the Toll signaling mutant MyD88−/ − flies are highly susceptible to C. parapsilosis. We also confirmed that the MyD88−/ − fly is a convenient invertebrate animal model to analyze virulence properties of different species and strains from the C. parapsilosis sensu lato complex as C. orthopsilosis, C. metapsilosis proved to be less virulent than C. parapsilosis sensu stricto and the N-mannan deficient C. parapsilosis och1Δ/Δ strain showed attenuated pathogenicity in this immunodeficient Drosophila background. We also found that Persephone protease is not required for detection and activation of Toll pathway during C. parapsilosis infection. Furthermore, we observed that Drosophila β-glucan receptor deficient flies where more sensitive to C. parapsilosis compared to wild-type flies; however, we could not find a clear dependence on the recognition of this receptor and the cell wall β-glucan exposure-induced host response. These studies establish this D. melanogaster infection model as an efficient tool in deciphering immune responses to C. parapsilosis as well as for assessing virulence factors produced by this emerging fungal predator.

Anti-tyrosinase properties of different species of turmeric and isolation of active compounds from Curcuma amada

Turmeric is traditionally used as a skin cosmetic in some religious and cultural occasions on the Indian subcontinent. In this study, we compared the tyrosinase inhibitory properties of four Curcuma spp., namely, C. xanthorrhiza, C. aromatica, C. amada, and C. zedoaria. Bioassay-guided isolation and purification of tyrosinase inhibitors using silica gel column and high-performance liquid chromatography. Structural identification of the compounds was conducted using 1H NMR, 13C NMR, and liquid chromatography-tandem mass spectrometry. C. amada showed the highest tyrosinase inhibitory activity, with an IC50 of 53.4 μg/mL. Therefore, it was chosen for the isolation and purification of tyrosinase inhibitors. The purified compounds were zederone (1), furanodienone (2), 1,5-epoxy-3-hydroxy-1-(3,4-dihydroxy-5-methoxyphenyl)-7-(4-hydroxyphenyl) heptanes (3), 3,5-dihydroxy-1-(3,4-dihydroxyphenyl)-7-(4-hydroxy-3-methoxyphenyl) heptanes (4) and 1,5-epoxy-3-hydroxy-1-(3,4-dihydroxy-5-methoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl) heptanes (5). The IC50 values for the mushroom anti-tyrosinase activity of compounds 1, 2, 3, 4, and 5 were 108.2, 89.2, 92.3, 21.7, and 41.3 µM, respectively. These compounds also inhibited intracellular tyrosinase activity, thus reducing melanin synthesis in B16F10 melanoma cells. Compound 4 showed significantly stronger anti-tyrosinase activity than that of arbutin (a positive control drug). No significant difference was observed in the tyrosinase inhibitory effect between compound 5 and arbutin. Our findings strongly suggest that C. amada is a promising source of natural tyrosinase inhibitors to prevent melanogenesis and could be used as a whitening cosmetic.

A Review on Antidiabetic Activity of Centaurea spp.: A New Approach for Developing Herbal Remedies.

Objective Diabetes mellitus (DM) is a long-life metabolic disorder, characterized by high blood glucose levels. The hyperglycemic condition generally leads to irreversible nerve injury and vascular damage. Among different types of diabetes, type 2 is more common and has spread all over the world. Although various therapeutic approaches have been developed to control type 2 DM, regulating blood glucose levels has still remained a controversial challenge for patients. Also, most prescription drugs cause different side effects, such as gastrointestinal disorders. Thus, developing novel and efficient antidiabetic agents possessing fewer adverse effects is in high demand. Method The literature was comprehensively surveyed via search engines such as Google Scholar, PubMed, and Scopus using appropriate keywords. Results Medicinal plants, both extracts and isolated active components, have played a significant role in controlling the blood glucose levels. Good-to-excellent results documented in the literature have made them a precious origin for developing and designing drugs and supplements against DM. Centaurea spp. have been traditionally used for controlling high blood glucose levels. Also, the antidiabetic properties of different species of Centaurea have been confirmed in recent studies through in vitro assays as well as in vivo experiments. Conclusion Potent results encouraged us to review their efficacy to open a new horizon for development of herbal antidiabetic agents.

Therapeutic Potential of Lindera obtusiloba: Focus on Antioxidative and Pharmacological Properties.

Lindera obtusiloba (LO) BLUME from the genus Lindera (Lauraceae) is a medicinal herb traditionally used in Southeast Asian countries. Indigenously, extracts of different parts of the plant have been used to improve blood circulation and treat allergy, inflammation, rheumatism, and liver diseases. LO is a rich source of therapeutically beneficial antioxidative phytochemicals, such as flavonoids, butenolides, lignans and neolignans. Moreover, recent studies have unravelled the pharmacological properties of several newly found active constituents of LO, such as anti-inflammatory antioxidants (+)-syringaresinol, linderin A, anti-atherosclerotic antioxidant (+)-episesamin, anti-melanogenic antioxidants quercitrin and afzelin, cytotoxic 2-(1-methoxy-11-dodecenyl)-penta-2,4-dien-4-olide, (2Z,3S,4S)-2-(11-dodecenylidene)-3-hydroxy-4-methyl butanolide, anti-allergic koaburaside, (6-hydroxyphenyl)-1-O-beta-d-glucopyranoside and 2,6-dimethoxy-4-hydroxyphenyl-1-O-beta-d-glucopyranoside and the antiplatelet-activity compound Secolincomolide A. These findings demonstrate that LO can be a potential source of antioxidants and other prospective therapeutically active constituents that can lead to the development of oxidative stress-mediated diseases, such as cardiovascular disorders, neurodegenerative disorders, allergies, inflammation, hepatotoxicity, and cancer. Here, the antioxidant properties of different species of Lindera genus are discussed briefly. The traditional use, phytochemistry, antioxidative and pharmacological properties of LO are also considered to help researchers screen potential lead compounds and design and develop future therapeutic agents to treat oxidative stress-mediated disorders.

Hybrid forms of mandarin (Citrus reticulata blanco var. Unchiu tan.) from interspecific crosses and their characteristics

Representatives of the genus Citrus L., which includes C. limon, C. sinensis, C. reticulata, C. paradisi, C. maxima, C. medica, C. aurantifolia and other species are the most important fruit crops in countries with subtropical and tropical climates. Cross-pollination, variability of sexual offspring fixed by apomixis, preserved during vegetative propagation contributed to the appearance of intergeneric and interspecific hybrids combining characters and properties of different species. The aim of this work was to carry out interspecific crosses to create biodiversity of Citrus reticulata Blanco var. unchiu Tan. and create new forms with breeding valuable traits. Six interspecific combinations of crossings with the involvement of different varieties were carried out, and a large variety of seedlings was obtained. In sexual offspring from interspecific crosses, a high degree of phenotypic variability is observed on the leaf blade, in shape, size, color of the fruit, thickness and separability of the peel, the presence and absence of seeds, as well as organoleptic properties. All these characteristics represent important criteria for the variety. According to the totality of morphological characters, 24 promising forms were selected. The combination of C. reticulata × C. maxima crossing is the most productive, which allowed us to identify the largest number of forms with breeding valuable traits. Forms Yub - P Nmik; Yub – P Nmik - 1; MV - P Azah; MV - P Azah - 1; MV - P Azah - 2; Kr - P Azah; Cr - P Azah – 1 are promising and are important for the creation of new large-fruited varieties of mandarin. From combination of crossbreeding with C. sinensis such forms as KV - ApV, KV-ApV-2, MV-ApV-1were identified, characterized by large-fruited, fruits with high organoleptic properties. Hybrids bred with C. medica, C. aurantifolia, C. limon meyer are important for creating citrus biodiversity with valuable traits.

Decrease in DNA methylation 1 (DDM1) is required for the formation of m CHH islands in maize.

DNA methylation plays a crucial role in suppressing mobilization of transposable elements and regulation of gene expression. A number of studies have indicated that DNA methylation pathways and patterns exhibit distinct properties in different species, including Arabidopsis, rice, and maize. Here, we characterized the function of DDM1 in regulating genome-wide DNA methylation in maize. Two homologs of ZmDDM1 are abundantly expressed in the embryo and their simultaneous disruption caused embryo lethality with abnormalities in cell proliferation from the early stage of kernel development. We establish that ZmDDM1 is critical for DNA methylation, at CHG sites, and to a lesser extent at CG sites, in heterochromatic regions, and unexpectedly, it is required for the formation of m CHH islands. In addition, ZmDDM1 is indispensable for the presence of 24-nt siRNA, suggesting its involvement in the RdDM pathway. Our results provide novel insight into the role of ZmDDM1 in regulating the formation of m CHH islands, via the RdDM pathway maize, suggesting that, in comparison to Arabidopsis, maize may have adopted distinct mechanisms for regulating m CHH.

Forest habitat invasions – Who with whom, where and why

Abstract Even though temperate forests have lower non-native plant species richness and cover in comparison to some other habitats, such as anthropogenically influenced habitats or some grassland habitats, several recent studies from Central Europe suggest that there has been an increase in the numbers and proportions of non-native species in forests. Previous studies on the level of invasion in forest habitats were usually conducted on a relatively coarse scale, often excluding plantations of non-native trees or analyzing them together as a group regardless of the different biological properties of different species. Therefore, a more detailed analysis would be helpful to obtain better insight into the processes taking place in forests, focusing not only on the analysis of the invasion level of different forest types at a finer scale (e.g., in various types of floodplain, beech or coniferous) but also on the character of the non-native plants found there (invasive status, frequencies and habitat preferences). In this study, we aimed to (i) compare the invasion level of various forest habitats (including forests dominated by non-native trees) in Slovakia with regard to different residence times and invasive status of non-native species, (ii) analyze whether forest habitats possess specific non-native species combinations, and (iii) determine the preferences of non-native plants with respect to specific forest habitats and the co-occurrence of other plant species with the most frequent non-native species. Our study confirmed that almost all forest habitats contained at least one non-native species. Native forests at lower elevations and closer to rivers were more invaded, while broadleaved, mixed and especially coniferous forests at higher elevations and ecologically strictly limited forests were less (or un-) invaded. Significant differences between various types of riparian and coniferous forests, emphasized the importance of the more detailed discrimination of the forest habitats in comparison with previous studies. Non-native tree plantations, which are among the most invaded forests, also deserve special attention. Some non-native trees form stable communities with typical native and non-native species, where non-native dominants can act as drivers of further changes in the vegetation composition, facilitating spread of other co-occurring non-native shrubs and herbs. Taking into consideration the potential negative impacts of some non-native plants on species composition, forest microclimate and soil chemistry, it would be advisable for foresters to factor this into forest management because their choice of planted species may both positively and negatively influence the level of invasion in managed forests.

N2O + CO reaction over single Ga or Ge atom embedded graphene: A DFT study

The possibility of using a single Ga or Ge atom embedded graphene as an efficient catalyst for the reduction of N2O molecule by CO is examined. We perform density functional theory calculations to calculate adsorption energies as well as analysis of the structural and electronic properties of different species involved in the N2O + CO reaction. The large activation energy for the diffusion of the single Ga or Ge atom on the C vacancy site of graphene shows the high stability of both Ga- and Ge-embedded graphene sheets in the N2O reduction. The activation energy needed for the decomposition of N2O is calculated to be 18.4 and 14.1 kcal/mol over Ga- and Ge-embedded graphene, respectively. The results indicate that the Ge-embedded graphene may serve as an effective catalyst for the N2O reduction. Moreover, the activation energy for the disproportionation of N2O molecules that generates N2 and O2 is relatively high; so, the generation of these side products may be hindered by decreasing the temperature.

Non-introgressive genome chimerisation by malsegregation in autodiploidised allotetraploids during meiosis of Saccharomyces kudriavzevii x Saccharomyces uvarum hybrids.

Saccharomyces strains with chimerical genomes consisting of mosaics of the genomes of different species ("natural hybrids") occur quite frequently among industrial and wine strains. The most widely endorsed hypothesis is that the mosaics are introgressions acquired via hybridisation and repeated backcrosses of the hybrids with one of the parental species. However, the interspecies hybrids are sterile, unable to mate with their parents. Here, we show by analysing synthetic Saccharomyces kudriavzevii x Saccharomyces uvarum hybrids that mosaic (chimeric) genomes can arise without introgressive backcrosses. These species are biologically separated by a double sterility barrier (sterility of allodiploids and F1 sterility of allotetraploids). F1 sterility is due to the diploidisation of the tetraploid meiosis resulting in MAT a /MAT α heterozygosity which suppresses mating in the spores. This barrier can occasionally be broken down by malsegregation of autosyndetically paired chromosomes carrying the MAT loci (loss of MAT heterozygosity). Subsequent malsegregation of additional autosyndetically paired chromosomes and occasional allosyndetic interactions chimerise the hybrid genome. Chromosomes are preferentially lost from the S. kudriavzevii subgenome. The uniparental transmission of the mitochondrial DNA to the hybrids indicates that nucleo-mitochondrial interactions might affect the direction of the genomic changes. We propose the name GARMe (Genome AutoReduction in Meiosis) for this process of genome reduction and chimerisation which involves no introgressive backcrossings. It opens a way to transfer genetic information between species and thus to get one step ahead after hybridisation in the production of yeast strains with beneficial combinations of properties of different species.

Preparation of organic–inorganic hybrid silica nanoparticles with contact antibacterial properties and their application in UV-curable coatings

Abstract With the increasing requirements of antibacterial in various fields, it is necessary to create ultraviolet (UV)-curable coating with antibacterial properties by adding antibacterial agents to coating formulations. Therefore, it is crucial to promote the development of coatings designed with UV-curable addition agents that possess excellent antibacterial activity and suitable mechanical properties. In this study, a series of silica nanoparticles was developed with photo-cross-linking and antibacterial properties. The effects of various grafting ratios of photosensitive groups and antimicrobial function groups on the dispersity and antibacterial performance of nanoparticles were evaluated. The findings indicate that nanoparticles modified with quaternary ammonium species possess good dispersity and antibacterial ability. The series of functional silica nanoparticles, which act as organic–inorganic hybrid UV-curable antibacterial agents, was added to soybean oil-based UV-curable coating formulations. The basic coating properties of different species of nanoparticles were systematically investigated. Antibacterial tests of coatings were also conducted. With a proper grafting ratio of antimicrobial function groups on nanoparticles, the coatings exhibit excellent antibacterial activity and favorable mechanical properties, and thus show promise for application as antibacterial coatings.