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• First report on in vitro mass propagation of Dendrobium Yuki White. • Concurrent shoot-root formation observed in MS with BA-NAA combination and additive AdS. • Matrix plot, network plot and PCA substantiated the effects of and association among PGRs. • 97% plantlets were acclimatized in equivolume coconut fibre and charcoal. A novel and accelerated one-step protocol for complete in vitro mass propagation of Dendrobium Yuki White was optimized for the first time. Rapid shoot-root initiation and multiplication was simultaneously achieved from apical shoot segment explants on Murashige and Skoog basal medium fortified with 0.5 mg L−1 N6-benzyladenine (BA), 0.1 mg L−1 α-naphthaleneacetic acid, along with 40 mg L−1 adenine sulphate as an additive. Maximum number of shoots per explant (12) was obtained within eight weeks of culture. Maximum number of root induction (17) and elongation (6.5 cm) were recorded within this period. On the other hand, the matrix plot, network plot, and principal component analyses illustrated the association of auxin-cytokinin and the multiple growth attributes under study. In a simple acclimatization procedure, involving primary acclimatization in charcoal blocks for six weeks, and followed by a combination of coconut fibre and charcoal (1:1; v v −1) with intermittent water spraying ensured 97% survival rate in the next ten weeks. Based on the comprehensive information developed in this study, this protocol should be of immense importance for large-scale production of planting materials as well as for exploring the possible comparative roles of the auxin-cytokinin combinations used in this study. [ABSTRACT FROM AUTHOR]

Self-assembly of disordered amyloid-beta (Aβ) peptides results in highly ordered amyloid fibrils. The structural information of the early-stage events and also in the presence of inhibitors is of great significance. It is challenging to acquire due to the nature of the amyloids and experimental constraints. Here, we demonstrate the cascade of aggregation (early to late) of the Aβ 25-35 peptide in the absence and presence of carvedilol, a nonselective β-adrenergic receptor blocker. The aggregation process of Aβ 25-35 peptide is monitored using Thioflavin T (ThT) fluorescence, dynamic light scattering (DLS), circular dichroism (CD), Raman spectroscopic techniques, and imaging experiments. We find that the Aβ 25-35 peptide undergoes an early-stage (3-6 h) helical intermediate formation across the fibrillation pathway using CD and Raman measurements. Carvedilol obstructs the helical intermediate formation of Aβ 25-35 peptide resulting in inhibition. CD spectra and deconvolution of the Raman bands suggest the β-sheet formation (24-100 h) in the absence of carvedilol. Spectroscopic results indicate a disordered structure for the peptide in the presence of carvedilol (24-100 h). Electron microscopy (EM) shows the formation of polymorphic fibrils for the peptide alone and non-amyloidal aggregates in the presence of carvedilol. Molecular docking study suggests that the plausible mode of interaction with carvedilol involves the C-terminal residues of the peptide. A schematic representation of carvedilol mediated inhibition of Aβ 25-35 fibrillation process. [Display omitted] • Aβ 25-35 peptide undergoes early-stage helix formation at pH 7.4 between 3 and 6 h. • Carvedilol inhibits Aβ 25-35 fibrillation perturbing ordered structure formation. • Aβ 25-35 peptide exhibits twisted and striated fibrillar polymorphism. • CD and Raman describe the structural features of early to late aggregation. • Biophysical techniques reveal a crucial role of Ile residues and carbazole moiety. [ABSTRACT FROM AUTHOR]

Abstract With the remarkable development in the field of nanotechnology, carbon-based nanomaterials (CNMs) have been widely used for numerous applications in different areas of the plant system. The current understanding about the CNMs' accumulation, translocation, plant growth responses, and stress modulations in the plant system is far from complete. There have been relentless efforts by the researchers worldwide in order to acquire newer insights into the plant-CNMs interactions and the consequences. The present review intends to update the reader with the status of the impacts of the different CNMs on plant growth. Research reports from the plant biotechnologists have documented mixed effects (which are dependent on CNMs' concentration) of the CNMs' exposure on plants ranging from enhanced crop yield to acute cytotoxicity. The growth and yield pattern vary from species to species and are dependent on the dosage of the CNMs applied. Studies found an increase in vegetative growth and yield of fruit/seed at lower concentration of CNMs, but a decrease in these observables were also noted when higher concentrations of CNMs were used. In general, at lower concentrations, CNMs were found to be effective in enhancing (water uptake, water transport, seed germination, nitrogenase , photosystem and antioxidant activities), activating (water channels proteins) and promoting (nutrition absorption); all these change when concentrations are raised. All these aspects have been reviewed thoroughly in this article, with a focus on the recent updates on the role of the CNMs in augmenting or retarding plant growth. Sections have been devoted to the various features of the CNMs and their roles in inducing plant growth, phytotoxic responses of the plants and overall crop improvement. Concluding remarks have been added to propose future directions of research on the CNMs-plant interactions and also to sound a warning on the use of CNMs in agriculture. Graphical abstract Unlabelled Image Highlights • Recent updates on the CNMs augmenting/retarding plant growth are discussed. • CNMs enhance nutrients and water uptake in plants. • CNTs improve seed germination in several plant species. • Carbon dots activate the plant photosystem. • MWCNTs facilitate water channels and increase nitrogenase activity. [ABSTRACT FROM AUTHOR]

With the overwhelmingly rapid advancement in the field of nanotechnology, the engineered nanomaterials (ENMs) have been extensively used in various areas of the plant system, including quality improvement, growth and nutritional value enhancement, gene preservation etc. There are several recent reports on the ENMs' influence on growth enhancements, growth inhibition as well as certain toxic impacts on plant. However, translocation, growth responses and stress modulation mechanisms of ENMs in the plant systems call for better and in-depth understanding. Herein, we are presenting a comprehensive and critical account of different types of ENMs, their applications and their positive, negative and null impacts on physiological and molecular aspects of plant growth, development and stress responses. Recent reports revealed mixed effects on plants, ranging from enhanced crop yield, epi/genetic alterations, and phytotoxicity, resulting from the ENMs' exposure. Creditable research in recent years has revealed that the effects of ENMs on plants are species specific and are variable among plant species. ENM exposures are reported to trigger free radical formation, responsive scavenging, and antioxidant armories in the exposed plants. The ENMs are also reported to induce aberrant expressions of microRNAs, the key post-transcriptional regulators of plant growth, development and stress-responses of plants. However, these modulations, if judiciously done, may lead to improved plant growth and yield. A better understanding of the interactions between ENMs and plant responses, including their uptake transport, internalization, and activity, could revolutionize crop production through increased disease resistance, nutrient utilization, and crop yield. Therefore, in this review, we are presenting a critical account of the different selected ENMs, their uptake by the plants, their positive/negative impacts on plant growth and development, along with the resultant ENM-responsive post-transcriptional modifications, especially, aberrant miRNA expressions. In addition, underlying mechanisms of various ENM-plant cell interactions have been discussed. [ABSTRACT FROM AUTHOR]

Tuberculosis – a disease caused by Mycobacterium tuberculosis ( Mtb ), is one of the most devastating disease. The discovery of Ser/Thr protein kinases (STPKs) in Mtb opened a new avenue for developing anti-tubercular inhibitors. The in-vivo inhibitory effects of many metal ions have been demonstrated in literature. But, one of the limitations of metal ions as inhibitors is their inability to traverse the hydrophobic membrane due to polar nature and their propensity for non-specific interactions. To overcome this, we attached a metal ion to 2-A9P – an analog derived from a cell permeable scaffold, 2-Aminopurine (2-AP) which is a known kinase inhibitor. We investigated the inhibitory potential of 2-AP and its analog 2-A9P against protein kinase B (PknB) and showed that both of these can inhibit Mtb STPKs. Next, we evaluated the latent inhibitory activity of metal ions and for the first time showed that they can inhibit the phosphotransfer reaction in PknB, PknG and PknL. Subsequently, 6 different metal complexes (MC) of 2-A9P were used for inhibitory studies and their estimated IC 50 values show that most MCs inhibited PknB with low micromolar potency. Further, MIC values determined for the six MCs against Mtb showed that MC-4 and MC-6 exhibit whole cell inhibitory activity. Cytotoxicity studies show that MC-4 and MC-6 do not affect cell viability of A549 cell lines, suggesting that these inhibitors can be further developed as anti-tubercular agents. [ABSTRACT FROM AUTHOR]

Digitalis L. (Foxglove, Plantaginaceae) genus is a representative of several medicinal ornamental plants that are widely used in the production of herbal medicines. Since the eighteenth century, human civilizations have been using the extracts from several Digitalis species for treating heart-related ailments. The active ingredient in the medicine is cardiac glycosides. Cardenolides, which are constituents of cardiac glycosides, have an important role in tumor therapy. Certain pharmacologically active compounds including cardenolides are isolated from plants, as the structural complexity of cardenolides impede an easy chemical synthesis. In modern plant biotechnology research, production of cardenolides in large-scale using in vitro techniques has become the need of the hour. The reasons are twofold: first, to reduce the excessive use of natural Digitalis population and second, to improve the plant quality vis-à-vis genetic preservation of the superior seeds for future use. The production of useful secondary metabolites depends on the overall wellness of the plant from which extraction is to be made. The subject matter of this review includes concurrent development and propagation of several Digitalis species based on direct and indirect regeneration methods. Herein, a compilation of up-to-date published research reports on in vitro culture of Digitalis L. has been presented, including the authors’ latest and yet-to-be-published work on Digitalis davisiana Heywood. The important steps to be followed for the implementation of any plant improvement/preservation program must include topic-wise requirements at various stages of micropropagation (viz., culture establishment, shoot multiplication, root induction and acclimatization) and also the requirements for plant regeneration (viz., somatic embryogenesis and organogenesis). These have been reviewed thoroughly and different methods for the in vitro production of cardenolides have been discussed. Critical comments on the prospects of highly scalable cultures and their importance to meet the ever-growing demand for Digitalis -derived products in pharmaceutical industries, have also been included. [ABSTRACT FROM AUTHOR]

The effect of hydrogen peroxide (H2O2) on callus cultures of four Digitalis species (Digitalis lamarckii, Digitalis trojana, Digitalis davisiana and Digitalis cariensis) increased catalase (CAT), superoxide dismutase (SOD), total phenolic, proline activity and cardiotonic glycoside production. Callus derived from hypocotyl explants was cultured on Murashige and Skoog medium supplemented with 0.25 mg L−1 indole-3-acetic acid (IAA) and 0.5 mg L−1 thidiazuron (TDZ). After a month of culture, callus was transferred to MS medium containing 10 mM H2O2 and then incubated for 6 h. The amount of five cardenolides (Lanatoside C, Digitoxin, Digoxigenin, Gitoxigenin and Digoxin) as well as CAT, SOD, total phenolic, proline activity from Digitalis species were compared. No digoxin was detected in all treatments and control groups. The total cardenolides estimated were in the order of D. lamarckii (586.65  μg g−1 dw), D. davisiana (506.79 μg g−1 dw), D. cariensis (376.60 μg g−1 dw) and D. trojana (282.39 μg g−1 dw). It was clear that H2O2 pre-treatment resulted in an increase in enzymatic and nonenzymatic antioxidants. However, a significant negative relationship between cardenolides production and overall activities of CAT, SOD, total phenolic and proline was evident. The described protocol here will be useful for the development of new strategies for a large-scale production of cardenolides. [ABSTRACT FROM AUTHOR]

Abstract: Loop-mediated isothermal amplification (LAMP) is at the forefront in the search for innovative diagnostics for rapid and specific amplification of target DNA under isothermal conditions. We have applied LAMP assay using SYBR Green for clear-cut naked eye detection of Leishmania (Leishmania) donovani in 200 clinical samples of visceral leishmaniasis (VL) and post-kala-azar dermal leishmaniasis (PKDL). The assay was positive in 53/55 VL blood samples (sensitivity, 96.4%; 95% confidence interval [CI], 87.7–99%), 15/15 VL bone marrow aspirate samples (sensitivity, 100%; 95% CI, 79.6–100%), 60/62 PKDL tissue biopsy samples (sensitivity, 96.8%; 95% CI, 88.9–99.1%), and 1/68 control samples (specificity, 98.5%; 95% CI, 92.1–99.7%). The assay was specific for L. (L.) donovani, the causative species for VL and negative for L. (L.) infantum, L. (L.) tropica, and L. (L.) major. This is the first comprehensive clinical study demonstrating the applicability of the LAMP assay for a rapid and reliable molecular diagnosis of VL and PKDL. [Copyright &y& Elsevier]

Abstract: This study describes, for the first time, an in vitro protocol for the direct development of somatic embryos and subsequent plant regeneration from hypocotyl segments excised from 21-days-old in vitro-germinated seedlings of Digitalis trojana Ivan (Helen of troy foxglove). Two sets of experiments were carried out, the first compared different concentrations of four cytokinins: N6-benzyladenine [BAP], 6-furfurylaminopurine [kinetin], 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea [TDZ], and 6-(4-hydroxy-3-methylbut-2-enylamino) purine [zeatin] alone, while the second set tested TDZ or BAP combinations with IAA (indole-3-acetic acid), IBA (indole-3-butyric acid) or NAA (α-naphthalene acetic acid). In the first set of experiments, TDZ was found the most effective at 1.0mg/l concentration, producing a mean of 10.7 somatic embryos per explant. In the second set, a combination of 1.0mg/l TDZ with 0.5mg/l IAA produced significantly more somatic embryos per explant (13.8 embryos) than with BAP (8.8 embryos). During subculture on growth regulator-free half-strength MS medium, somatic embryos gradually developed into plantlets. Regenerated plantlets were successfully transplanted and grown in a greenhouse environment. The efficient regeneration protocol reported here provides an important method of micropropagation of this plant. Furthermore, this protocol may be used for a large-scale production of cardenolides and genetic transformation of this valuable medicinal plant for its further improvement. [Copyright &y& Elsevier]

Abstract: LUCI, the Laboratory for Underground CO2 Investigations, is an experimental facility being planned for the DUSEL underground laboratory in South Dakota, USA. It is designed to study vertical flow of CO2 in porous media over length scales representative of leakage scenarios in geologic carbon sequestration. The plan for LUCI is a set of three vertical column pressure vessels, each of which is ∼500 m long and ∼1 m in diameter. The vessels will be filled with brine and sand or sedimentary rock. Each vessel will have an inner column to simulate a well for deployment of down-hole logging tools. The experiments are configured to simulate CO2 leakage by releasing CO2 into the bottoms of the columns. The scale of the LUCI facility will permit measurements to study CO2 flow over pressure and temperature variations that span supercritical to subcritical gas conditions. It will enable observation or inference of a variety of relevant processes such as buoyancy-driven flow in porous media, Joule-Thomson cooling, thermal exchange, viscous fingering, residual trapping, and CO2 dissolution. Experiments are also planned for reactive flow of CO2 and acidified brines in caprock sediments and well cements, and for CO2-enhanced methanogenesis in organic-rich shales. A comprehensive suite of geophysical logging instruments will be deployed to monitor experimental conditions as well as provide data to quantify vertical resolution of sensor technologies. The experimental observations from LUCI will generate fundamental new understanding of the processes governing CO2 trapping and vertical migration, and will provide valuable data to calibrate and validate large-scale model simulations. [Copyright &y& Elsevier]

Abstract: Photo-degradation of curcumin in the presence of TiO2 nanoparticles has been studied in water–methanol and water–acetonitrile mixed solvents. Curcumin was found to form charge transfer (CT) complexes with TiO2 nanoparticles. The binding constant of the CT complexes has been determined. Curcumin was found to undergo photo-degradation under UV–vis and only visible light irradiations. Photo-degradation was investigated in the presence of external electron quenchers like methyl violegen and dissolved oxygen and hole quenchers like iodide ions in a de-aerated condition. The presence of oxygen was found to enhance the photo-degradation processes. The photo-degradation was found to be completely quenched in the presence of iodide ions in both the solvent mixtures in a de-aerated condition. A reaction pathway for the photo-degradation of curcumin in the presence of TiO2 nanoparticles has been proposed. This study has been successfully applied to remove the yellow turmeric stain from cotton fabrics. [Copyright &y& Elsevier]

Abstract: Lectins are carbohydrate-binding proteins found in plants, viruses, bacteria, and animal cells having the ability to distinguish complex carbohydrate structures on cell surfaces. The ubiquity of lectin–carbohydrate interactions support the notion of a glycocode, which is related to highly specific recognition of carbohydrate display expressed on different cell surfaces of normal and diseased origin. The importance of these interactions in cell biology and medicine has been realized with the applications ranging from blood typing to clinical diagnostics. This paper reports synthesis of some symmetrical carbohydrate derivatives, their interaction with lectin Concanavalin A and ultrastructural force microscopic studies of the complex formation. Preliminary efforts have been made to construct possible models to explain the nature of interaction within these assemblies. [Copyright &y& Elsevier]

Abstract: Self-assembly is routinely used for the design and fabrication of new and advanced materials. Biological building blocks such as short peptides undergo self-assembly to reveal a variety of hierarchical structures such as nanotubes, fibers, and spherical structures. Peptide-based soft spherical structures are potentially useful for a variety of applications including vehicles for drug delivery and biological molecules. This report describes a tripalmitoylated triskelion ditryptophan peptide conjugate (5) that self-assembles to form hollow spheres along with pores on the surface when higher concentration of the dichloromethane was used, but forms fiber structures when heated in toluene solvent. [Copyright &y& Elsevier]

Abstract: This study probes the beneficial role of aromatic side chains in peptide self-assembly by choosing four diketopiperazine model systems variably composed of glycine, proline, phenylalanine, and tryptophan residues. [Copyright &y& Elsevier]

Abstract: This report describes an accelerated self-assembly of a synthetic cyclic hexapeptide in the presence of alkali metal ions. Time-dependent aggregation of hexapeptide was considerably influenced upon co-incubation with monovalent metal ions, of which K+ afforded the most significant effect both on the time-scale required for self-assembly and on the morphology of aged structures. Metal ion adducts formation ability of the hexapeptide was confirmed by electrospray ionization mass spectrometry measurements and 13C NMR spectrometry. The effect of metal ion binding on peptide structure was also probed by circular dichroism, optical microscopy, and scanning electron microscopy. K+ ions not only interacted more efficiently with the hexapeptide enabling it to reach conformational state(s) conducive for self-assembly, but also altered the morphologies of the aged peptide fibers, when compared to the unmetalated peptide. [Copyright &y& Elsevier]

Abstract: Biological molecules serve as convenient scaffolds for the construction of nanoscopic architectures which can effectively interact with small molecules and metal complexes to extend their scope for nano(bio)technological applications. Metalloproteins possess natural metal ion binding motifs and the possibility of using these sequences to generate metalated peptide conjugates with defined metal ion coordination offers a facile entry into metalated supramolecular aggregates. This report describes the formation of metalated fibers from Cu-binding octarepeat motifs of the prion protein. Conjugate 1 effectively binds copper, silver, and manganese, leading to persistent length and thermally stable peptide fibers, which could be applied for molecular bioelectronic applications. [Copyright &y& Elsevier]

Abstract: We report construction of a bis-pentapeptide conjugate 4 containing truncated pentapeptide sequence from prion octarepeats. Its copper-laden derivative 5 demonstrated a propensity for aggregate formation, which was studied by atomic force microscopy. Oxidative biochemical transformations catalyzed by 5 were evaluated by nucleic acid cleavage and by neurotransmitter oxidation, in the presence of external co-oxidants. Preliminary mechanistic analysis provides a hint for the involvement of reactive oxygen species in such transformations. [Copyright &y& Elsevier]

Cleavage of a model phosphate ester and supercoiled plasmid DNA by a Cu(I)·adenylated polymer template and preliminary mechanistic investigations are reported. A novel paradigm for the design of recyclable nucleolytic reagents allowing multiple use of this catalyst is also demonstrated [Copyright &y& Elsevier]

This paper reports synthesis and plasmid modification activities of a new class of insoluble copper-metalated diglycine conjugates, containing aliphatic linkers of varying length. Besides providing significant rate enhancement for model phosphate ester cleavage, these constructs also displayed efficient supercoiled plasmid scission, in the absence of co-oxidants, under heterogeneous catalytic conditions. [Copyright &y& Elsevier]

Non-natural, functional RNA molecules, such as short interfering (si) RNAs, aptazymes, maxizymes and intramers, allow modulation of gene function at the mRNA or protein level. This review discusses recent advances made in the expression and application of these functional RNAs and illustrates how engineered, intracellularly active RNAs can serve as promising tools for understanding the function of genes and their protein products or as potential therapeutic agents. [Copyright &y& Elsevier]

Graphical abstract Highlights • We have synthesized dehydrophenylalanine containing tetrapeptide. • Peptide folded as an overlapping beta-turn of type III/III conformation. • The Peptide has been shown as a fluorometric sensor for Hg2+ metal ion. • Peptide self-assembled into spherical nanoparticles. • Addition of Hg2+ in peptide solution results in fusion of nanospheres. Abstract The tetrapeptide (Bz- Δ Phe(p- NPh 2)- l -DOPA(protected)- l - Phe- l - Phe-OMe was designed to incorporate seven phenyl rings so that it’s conformation, self-assembly and application in Hg2+ ions sensing could be studied. Peptide molecules adopted an overlapping β-turn of type III/III conformation in crystals. The peptide showed a highly selective turn-on response towards mercuric ion over other metal ions with a 10-fold enhancement in fluorescence intensity. This intensity change coupled with the selectivity of the peptide towards mercury allowed us to demonstrate simple colorimetric dip sensing of Hg2+ ions. The technique provides a highly selective and effective way to detect Hg2+ ions. The peptide also self-assembled into nanospheres with diameter ranges from 100 to 500 nm. Mercuric ion coordination enabled these peptide nanospheres to aggregate into well-defined nanoparticles. The enhanced fluorescence upon Hg2+ addition demonstrates that peptide scaffolds can be exploited in the development of different selective sensors. [ABSTRACT FROM AUTHOR]

We have synthesized a modified adenine ligand, with an azide appendage at N9 position, to extend the possibilities of coordination within chemically modified purine framework. Consequently, different coordination modes of this newly synthesized ligand afforded formation of dimeric, 1D- and 2D-polymeric structures, as a result of stoichiometry variation of silver ions. Monodentate coordination mode of azide containing adenine nucleobase led to a discrete dimer 1 with AgClO 4 , while 1D-polymer 2 was formed with AgNO 3 through bidentate coordination mode of the ligand. Notably, a 2D-coordination polymer 3 , with rectangular hexameric framework was obtained with AgNO 3 as a result of a unique tridentate coordination mode of ligand, with additional assistance provided by weakly coordinating azide appendage. [ABSTRACT FROM AUTHOR]

Globally, infections due to multi-drug resistant (MDR) Gram-negative bacterial (GNB) pathogens are on the rise, negatively impacting morbidity and mortality, necessitating urgent treatment alternatives. Herein, we report a detailed bio-evaluation of an ultrashort, cationic lipopeptide 'SVAP9I' that demonstrated potent antibiotic activity and acted as an adjuvant to potentiate existing antibiotic classes towards GNBs. Newly synthesized lipopeptides were screened against ESKAPE pathogens and cytotoxicity assays were performed to evaluate the selectivity index (SI). SVAP9I exhibited broad-spectrum antibacterial activity against critical MDR-GNB pathogens including members of Enterobacteriaceae (MIC 4–8 mg/L), with a favorable CC 50 value of ≥100 mg/L and no detectable resistance even after 50th serial passage. It demonstrated fast concentration-dependent bactericidal action as determined via time-kill analysis and also retained full potency against polymyxin B-resistant E. coli , indicating distinct mode of action. SVAP9I targeted E. coli 's outer and inner membranes by binding to LPS and phospholipids such as cardiolipin and phosphatidylglycerol. Membrane damage resulted in ROS generation, depleted intracellular ATP concentration and a concomitant increase in extracellular ATP. Checkerboard assays showed SVAP9I's synergism with narrow-spectrum antibiotics like vancomycin, fusidic acid and rifampicin, potentiating their efficacy against MDR-GNB pathogens, including carbapenem-resistant Acinetobacter baumannii (CRAB), a WHO critical priority pathogen. In a murine neutropenic thigh infection model, SVAP9I and rifampicin synergized to express excellent antibacterial efficacy against MDR-CRAB outcompeting polymyxin B. Taken together, SVAP9I's distinct membrane-targeting broad-spectrum action, lack of resistance and strong in vitro and in vivo potency in synergism with narrow spectrum antibiotics like rifampicin suggests its potential as a novel antibiotic adjuvant for the treatment of serious MDR-GNB infections. [Display omitted] • SVAP9I is active against a broad-range of MDR-GNB. • SVAP9I shows concentration-dependent bactericidal activity against MDR E. coli with no detectable resistance. • SVAP9I damages both membranes inducing ROS generation and intracellular ATP depletion. • SVAP9I acts as a potent antibiotic adjuvant sensitizing multiple MDR GNBs to narrow-spectrum antibiotics in vitro. • SVAP9I synergizes with rifampicin against CRAB in vivo murine thigh infection model. [ABSTRACT FROM AUTHOR]

• The secondary metabolites and enzymatic activity were accelerated by abiotic stress. • 45 °C was the most effective treatment increasing the amount of p -coumaric acid (51.74-fold), overall detected phenolic enhancement (55.14%), and total flavonoid content. • CuSO 4 was the most effective treatment increasing the amount of luteolin (17.76-fold) and apigenin (15.56-fold). • The most common phenolic molecule in all callus cultures was chlorogenic acid. • HgCl 2 was the most effective application increasing SOD and CAT enzyme activity, total phenol and proline content. Bellis perennis L., common daisy, is a beneficial medicinal plant used in folk medicine to treat skin diseases, wounds, sore throats, common colds, inflammation, and rheumatism. The objective of this study was to determine the effect of 4 different abiotic stress applications [mercury chloride (HgCl 2), copper sulfate (CuSO 4), high temperature (45 °C) and ultraviolet radiation (UV)] on individual phenolic constituents, non-enzymatic antioxidant activities (free radical scavenging activity, total phenol-flavonoid content, and proline level), and enzymatic antioxidant activities [superoxide dismutase (SOD) and catalases (CAT)] in common daisy callus cultures. Quantification of the 21 phenolic substances was performed using LC-ESI-MS/MS analysis and all applied stress applications increased specific phenolic constituents comparing with control (no exposure to any stress). Heavy metal stresses (HgCl 2 and CuSO 4) and high temperature application enhanced the quantity of the selected phenolic substances more than UV-radiation stress. The most noticeable increased quantities were observed with high temperature stress in p -coumaric acid (51.74-fold), and with CuSO 4 stress in luteolin (17.76-fold) and apigenin (15.62-fold). Chlorogenic acid was the most prevalent phenolic compound in all tested callus extract including control. Although the first highest total phenol content was obtained with HgCl 2 exposure and then followed by high temperature stress, the first highest total flavonoid content was obtained with high temperature stress and then UV radiation. The antioxidant capacity was significantly enhanced (2.11 fold increase) with CuSO 4 stress application. Stress-related enzymatic antioxidant activity (SOD and CAT) was elevated the most with HgCl 2 stress. Similarly, the highest proline content was obtained with HgCl 2 treatment. These findings showed the ability of the phenolic compounds to protect common daisy against harmful heavy metals, high temperature and UV-radiation stresses. The adaptation of the callus under abiotic stress conditions developed here may be useful for the production of optimized phenolic compounds of common daisy and the exploitation of other medicinal species of interest. [ABSTRACT FROM AUTHOR]

Abstract: This communication describes crystallographic investigation of a dicopper complex of modified adenine nucleobase containing a Cu2O2 core. This arrangement is remarkably similar to active sites present in some copper-containing redox enzymes. Interestingly, this complex is also competent in catalyzing redox reactions, suggesting the possibility of catalytically competent primitive metal-nucleobase systems. [Copyright &y& Elsevier]

Abstract: A C 3-symmetric ferrocenylated ditryptophan construct was synthesized and the morphology of its self-assembled structure was studied. Ferrocenylated soft structures so obtained interacted with cyclodextrin resulting in increased tryptophan fluorescence and disruption of the self assembled structure. [Copyright &y& Elsevier]

Abstract: The triskelion peptide conjugate 1, having a Trp–Trp dipeptide unit on the three arms, was synthesized and studied for the interaction of peptide-based soft structures with metal ions, by fluorescence and microscopic analyses. We observed that fluorescence was significantly quenched upon addition of Cu(II) metal ions, whereas the addition of other metal ions also caused moderate to insignificant changes in the fluorescence emission, suggesting specificity of this triskelion peptide 1 for Cu(II) ions. The addition of Cu(II) and other metal ions also altered the morphology of preformed vesicles obtained from triskelion peptide 1 in a concentration-dependent fashion, as observed from microscopic analysis. Such metal-responsive soft structures may find potential use as novel materials for delivery and sensing applications. [Copyright &y& Elsevier]

Abstract: This manuscript describes one-pot, in situ synthesis of organoapatite-gold nanoparticle composite and its characterization by XRD, energy dispersive X-ray analysis, atomic force, and scanning electron microscopy. This methodology offers a different approach into the synthesis of zerovalent metal-mineral-phase nanocomposites having potential application as osteointegrative ceramics. [Copyright &y& Elsevier]