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Gymnema sylvestre R.Br., a pharmacologically important herb vernacularly called Gur-Mar (sugar eliminator), is widely known for its antidiabetic action. This property of the herb has been attributed to the presence of bioactive triterpene glycosides. Although some information regarding pharmacology and phytochemical profiles of the plant are available, no attempts have been made so far to decipher the biosynthetic pathway and key enzymes involved in biosynthesis of steryl glucosides. The present report deals with the identification and catalytic characterization of a glucosyltransferase, catalyzing biosynthesis of steryl glycosides. The full length cDNA (2572 bp) contained an open reading frame of 2106 nucleotides that encoded a 701 amino acid protein, falling into GT-B subfamily of glycosyltransferases. The GsSGT was expressed in Escherichia coli and biochemical characterization of the recombinant enzyme suggested its key role in the biosynthesis of steryl glucosides with catalytic preference for C-3 hydroxyl group of sterols. To our knowledge, this pertains to be the first report on cloning and biochemical characterization of a sterol metabolism gene from G. sylvestre R.Br. catalyzing glucosylation of a variety of sterols of biological origin from diverse organisms such as bacteria, fungi, and plants. [ABSTRACT FROM AUTHOR]

The essentiality of DNA Gyrase in basic cellular processes in bacterial pathogens makes it an ideal drug target. Though the Gyrase has a conserved mechanism of action, the complete DNA wrapping and binding process is still unknown. In this study, we have identified six arginine residues R556, R612, R667, R716, R766, and R817 in the DNA GyraseA – C-terminal domain from Salmonella enterica serovar Typhi (StGyrA-CTD) to be essential for DNA wrapping and sliding by a sequence and structure analysis. Through site-directed mutagenesis and EMSA studies, we observed that the substitution of R667 (blade 3) and R716 (blade 4) in StGyrA-CTD led to loss of DNA binding. Whereas, upon mutation of residue R612 (blade2), R766 (blade5) and R817 (blade6) along with supporting residue R712 (blade 4) a decrease in binding affinity was seen. Our results indicate that R667 and R716 act as a pivot point in DNA wrapping and sliding during gyrase catalytic activity. In this study, we propose that the DNA wrapping mechanism commences with DNA binding at blade3 and blade4 followed by other blades to facilitate the DNA sliding during supercoiling activity. This study provides a better understanding of the DNA binding and wrapping mechanism of GyrA-CTD in DNA Gyrase. [ABSTRACT FROM AUTHOR]

Topological quantum phenomena due to the presence of both Dirac fermions and flat bands in Kagome semimetal CoSn promise novel transport properties. In Kagome materials, the transport properties can be enhanced by moving the position of the flat band and Dirac fermions with doping. Here, we have investigated the magnetotransport and electronic properties by Fe doping in CoSn. A large positive magnetoresistance (MR) of ≈ 105% at 3 K and 8 T magnetic field has been observed in CoSn. Fe doping in Co 1 − x FexSn gives rise to negative MR with a large negative value for x = 0.2 (−8.4%) but decreases for x = 0.3 (−3.7%) and x = 0.4 (−2.7%). Tuning of MR from positive to negative values with Fe doping in CoSn is associated with the changes in energy position of the localized flat band and emergence of quasi-localized states near the Fermi level. The systematic variation of MR with increasing x depends both on the structural changes due to increase in the lattice parameters and on the near neighbor interactions of the Sn atoms with the Co atoms in the Kagome plane. The origin of quasi-localized states is associated with the electron hopping and the variation in the strength of localization with doping that leads to tunable MR properties in Co 1 − x FexSn. [ABSTRACT FROM AUTHOR]

Abstract: β-Ga2O3 nanostructures including nanowires, nanoribbons and nanosheets were synthesized via thermal annealing of gold coated GaAs substrates in N2 ambient. GaAs substrates with different dopants were taken as the starting material to study the effect of doping on the growth and photoluminescence properties of β-Ga2O3 nanostructures. The nanostructures were investigated by Grazing Incident X-ray Diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Energy Dispersive X-ray Spectroscopy, room temperature photoluminescence and optical absorbance. The selected area electron diffraction and High resolution-TEM observations suggest that both nanowires and nanobelts are single crystalline. Different growth directions were observed for nanowires and nanoribbons, indicating the different growth patterns of these nanostructures. The PL spectra of β-Ga2O3 nanostructures exhibit a strong UV-blue emission band centered at 410nm, 415nm and 450nm for differently doped GaAs substrates respectively. A weak red luminescence peak at 710nm was also observed in all the samples. The optical absorbance spectrum showed intense absorption features in the UV spectral region. The growth and luminescence mechanism in β-Ga2O3 nanostructures are also discussed. [Copyright &y& Elsevier]

Abstract: Single phase, PLZT powder was synthesized using gel-combustion route. It has been observed that fuel-to-oxidant ratio affects the initial phase formation. Higher fuel content leads to direct formation of crystalline perovskite PLZT powder due to substantial rise in the temperature during the redox reaction. Perovskite PLZT phase formation takes place at 550°C, without any intermediate phase formation, for stoichiometric fuel-to-oxidant ratio. The crystallite size was found to be independent of fuel-to-oxidant ratio when the ash is heated above 700°C. [Copyright &y& Elsevier]

Abstract: Present paper describes microstructural and mechanical characterization of laser-clad composite joint made of Stellite 21 and type 316L stainless steel (SS). The study has been broadly performed on two kinds of laser-clad specimens viz. (i) involving direct deposition of Stellite 21 on SS and (ii) involving gradient in chemical composition across substrate/clad interface. Both kinds of specimens exhibited nearly similar tensile strength, which was higher than that of SS in the interface region. Inter-dendritic carbides provided low energy fracture path in laser-clad deposits of Stellite 21. Both direct and graded interfaces of laser-clad specimens exhibited superior fatigue strength than the SS substrate. Instrumented impact testing brought out distinct difference in the mode of crack propagation across direct and the graded clad specimens. In contrast to initiation-controlled brittle crack propagation across the interface region in “direct clad” specimens, crack propagation across “graded interface” was marked with significant plastic deformation. [Copyright &y& Elsevier]

Nanotextured high density Mg-doped and undoped GaN were obtained using photoelectrochemical etching. Interesting features are observed in the temperature dependent photoluminescence (PL) studies of these nanotextured materials. First, the PL intensity of the excitonic emissions shows more than three orders of enhancement. At low temperature, the peak energy shows a blueshift with temperature. This phenomenon is attributed to the formation of excitonic band-tail states. Second, the excitonic emissions in the nanotextured samples are redshifted compared to the as-grown GaN suggesting strain relaxation. Third, the blue luminescence band (2.7–2.9 eV in Mg-doped GaN) shows a large redshift, which is not consistent with strain relaxation calculated from excitonic band. Furthermore, temperature dependence of the blue luminescence band energy shows an asymmetric S-shaped behavior in nanotextured GaN. All these observations are explained by invoking an increase in carrier localization due to an increase in potential fluctuation created by the nanotexturization process. [ABSTRACT FROM AUTHOR]

Abstract We report the structural and optical properties of ternary α-(Ga x Cr (1- x)) 2 O 3 with 0 ≤ x ≤ 0.45 which is synthesized by solid state reaction method. Single phase with space group R-3c is obtained for the gallium composition range of 0 ≤ x ≤ 0.45 and further increase in Ga concentration results in appearance of secondary C 2/ m phase corresponds to Ga 2 O 3. Variations in the in-plane ’ a’ and out of plane ’ c’ lattice parameters shows a clear daviation from the Vegard's law with the bowing parameters of −0.0510 Å and 0.0305 Å respectively. Extended X-ray absorption fine structure (EXAFS) spectroscopy shows larger values of Ga-O bond lengths, which elucidate the deviation in lattice parameters from the Vegard's law and immisibility of Ga in Cr 2 O 3 lattice. Diffuse reflectance spectroscopy (DRS) confirms a blue shift of 0.5 eV in the band gap of α-(Ga x Cr (1- x)) 2 O 3. It has also observed that Cr 3d level shifted towards the O 2p level in the valence band which has been reconfirmed by photo electron spectroscopy. The observed shift indicates enhancement of mixing between these levels which can leads to further delocalization of hole states in the valence band responsible for p-type conduction in the α-Cr 2 O 3. These results suggest that ternary α-(Ga x Cr (1- x)) 2 O 3 (0 ≤ x ≤ 0.45) can be useful in the field of UV transperant electronics and photodetectors. Highlights • Synthesis of α-(Ga x Cr (1- x)) 2 O 3 (0 ≤ x ≤ 0.45) by solid sate reaction method. • Deviation of lattice parameters from the Vegard's law and immiscibility of Ga is discussed. • Tunability of ∼0.5 eV in the bandgap of α-Cr 2 O 3 as a function of Ga composition. • Enhancement in the mixing of Cr d and O 2p states in the valance band. [ABSTRACT FROM AUTHOR]

Lactoperoxidase (LPO) is a member of mammalian heme peroxidase superfamily whose other members are myeloperoxidase (MPO), eosinophil peroxidase (EPO) and thyroid peroxidase (TPO). In these enzymes, the heme moiety is linked to protein through two or three covalent bonds. In the mature LPO, the heme moiety is linked to protein through two ester bonds with highly conserved glutamate and aspartate residues. The previously reported structures of LPO have confirmed the formation of two covalent linkages involving Glu258 and Asp108 with 1-methyl and 5-methyl groups of pyrrole rings A and C respectively. We report here a new form of structure of LPO where the covalent bond between Glu258 and 1-methyl group of pyrrole ring A is present only in a fraction of protein molecules. In this case, the side chain of Glu258 occupies two distinct positions, each of which has a 0.5 occupancy. In one position, it forms a normal ester covalent linkage while in the second position, the side chain of Glu258 is located in the middle of the substrate binding site on the distal heme side. In this position, the atom of the side chain of Glu258 forms several contacts with atoms of other residues and heme moiety. Out of the two observed positions of the side chain of Glu258, the former contributes to the stabilization of heme position and improved catalytic action of LPO while the latter is responsible for the reduced stability of the heme position as well as it blocks the substrate binding site. [ABSTRACT FROM AUTHOR]

Nanocomposites of CdS nanocrystals (NCs) embedded in a polyvinyl pyrrolidone are grown using one-step chemical bath deposition technique. While this method eliminates an additional step for the growth of NCs, it also leads to the formation of nearly monodispersive CdS NCs as indicated by absorption, reflection, and photoluminescence spectroscopy. Further, scanning electron microscopy, energy-dispersive spectroscopy, and transmission electron microscopic investigations reveal the formation of nearly monodispersive CdS NCs (~6 to 10 nm) embedded in PVP spheres of sizes ~100 to 600 nm. Systematic study of variation in Cadmium acetate (Cd ion source), Thiourea (S ion source), PVP concentration, deposition time, and heating/cooling cycles elucidates the co-operative growth mechanism for CdS-PVP nanocomposite. The experimental observations of this study are corroborated with existing theoretical simulations for nanocomposite growth, which explicates that collapse of PVP into a sphere is crucial to inclusion of only nearly monodispersive CdS NCs. Important insights obtained from this work give control on the growth of nearly monodispersive CdS NCs embedded in PVP, using a simple and inexpensive growth technique. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic behavior of a few pulsed laser deposited soft ferromagnetic thin films of Ni–Fe–Mo alloys of different thickness on sapphire single crystals is interpreted on the basis of their structural characteristics. Highly textured thin films have high void density due to island-like growth. X-ray reflectivity (XRR) of the thin films indicate that instead of a uniform density there are effectively three layers with density gradient across the thickness, which is further supported by atomic force microscopy and cross-sectional scanning electron microscopy. Rutherford backscattering spectroscopy and energy dispersive spectrum measurements reveal that the composition in the films is not too far from that of the bulk target with a trend of enhanced Fe yield in the films. The structural disorder strongly affected the magnetic property of the films resulting in much higher values of the Curie temperature T C and coercive field H C than those of the bulk targets. Bifurcations of low-field zero-field-cooled and field-cooled magnetization reflect the disorder-induced anisotropy in the thin films. The spin wave stiffness constants D are higher than their bulk counterparts which are supportive of the enhanced Fe yield in the films. The saturation magnetization, M calculated from measurements in field transverse to the films strongly supports the thickness found from XRR. Finally, even the 10nm thin films have sizable M and H C and T C >300K, making them good candidates for magnetic applications. Overall, the magnetic behavior and the structural characteristics have reasonably complemented each other. [Copyright &y& Elsevier]

Abstract: The pitting corrosion and sensitization in laser rapid manufactured specimens of type 316L stainless steel are studied and compared with its wrought and weld deposit (by plasma transferred arc welding-PTAW) counterparts. With respect to wrought specimens, the laser rapid manufactured specimens exhibited lower pitting corrosion resistance as well as higher degree of sensitization. However, pitting corrosion resistance of laser rapid manufactured specimens is largely similar to that of PTAW-deposited specimens. Relatively lower pitting corrosion resistance of laser rapid manufactured and PTAW-deposited specimens are attributed to their cast microstructure and associated micro-segregation effects as expected. Repeated exposure to sensitization temperature range (773–1073K) during multiple layer deposition coupled with slower rate of cooling during later part of laser rapid manufacturing resulted in sensitization, giving rise to continuous corrosion attack along the grain boundaries. Solution annealing is found to be helpful in healing the associated chromium depletion and decreasing the degree of sensitization with modest improvement in pitting resistance. Primary mode of solidification in laser rapid manufactured specimens of type 316L stainless steel influenced potential sites for initiation of pitting corrosion. In primary ferrite solidified regions, initiation of pitting corrosion occurred preferentially at δ-ferrite/austenite boundaries whereas core of austenite cells/dendrites and grain boundaries were the preferred sites for initiation of pitting corrosion in primary austenite solidified regions. These studies provide insight into the basic corrosion mechanisms of laser rapid manufactured specimens of type 316L stainless steel. [Copyright &y& Elsevier]

Abstract: Fatigue crack growth and fracture toughness characteristics of laser rapid manufactured (LRMed) Inconel 625 compact tension specimens of thickness 12 and 25mm were investigated. Fatigue crack propagation in all the specimens investigated in the stress intensity range (ΔK) of 14–38MPa√m, exhibited stage II crack growth in Paris’ regime with nearly same slopes of crack growth per cycle versus ΔK plot. Fatigue crack growth rates in the LRMed specimens of present study were found to be lower than the reported values for wrought Inconel 625 in the ΔK range of 14–24MPa√m and above this range they tended to coincide. X-ray diffraction patterns of the fractured surfaces revealed that the crack propagated along the growth direction of the specimens which was predominantly along the (111) plane. The fracture toughness values (J 0.2) for LRMed Inconel 625 specimens were found to be in the range of about 200–255kJ/m2. The LRMed specimens exhibited stable crack growth during the J-integral test. [ABSTRACT FROM AUTHOR]

Abstract: A two-step growth process of gallium phosphide (GaP) epilayer on silicon substrate is carried out using metal organic vapor-phase epitaxy (MOVPE). This process includes the growth of a low-temperature GaP nucleating layer and a high-temperature GaP epilayer. In the first step, a GaP nucleating layer of thickness ∼80nm with high V/III ratio ∼1725 is grown at 425°C. This is followed by the growth of a GaP layer of thickness ∼760nm with V/III ratio ∼100 at 770°C. The total thickness of the epilayer is ∼845nm as measured on a cross-section by a scanning electron microscope (SEM). A GaP layer grown by the two-step growth process shows significant improvement in morphology compared with that grown by the single-step process, as confirmed by Raman and SEM studies. High-resolution X-ray diffraction studies show that the epilayer is of single crystalline nature and structurally coherent with the silicon substrate. Epilayers grown using the two-step process show reduced dislocation density and micro-strains, with significant improvements in their structural properties. These layers also show n-type behavior with an electron density of ∼8.5×1017 cm−3, while the single-step-grown layers show p-type behavior. This change in type is explained by a reduced/increased incorporation of silicon into phosphorus/gallium sites, respectively, i.e. a predominant donor nature of silicon in GaP grown by the two-step growth process. Photoluminescence (PL), surface photovoltage spectroscopy (SPS) and transport measurements confirm a significant reduction in sub-band gap states and carrier density. [Copyright &y& Elsevier]

Abstract: We have deposited thin layers of ZnSe on (001) oriented GaAs substrates by pulsed laser deposition at different incident laser fluence (referred to as normal geometry) and in an off-axis geometry where the plasma plume direction is at an angle of ∼25° away from the direction of the substrate. The crystalline quality of these layers has been studied by high-resolution X-ray diffraction measurements and Raman scattering. We find that we are in a position to deposit pseudomorphic strained layers of ZnSe on GaAs in the off-axis deposition geometry when the ZnSe layer thickness is less than the critical thickness of ZnSe on GaAs i.e. 150 nm. Secondary ion mass spectroscopy, scanning electron microscopy, photoluminescence and electrical transport measurements have also been carried out in all the ZnSe layers and the results of all the above characterizations have been compared for the normal geometry and the off-axis geometry of deposition. All the results indicate that the ZnSe layers deposited in the off-axis geometry have better crystalline quality and an improved interface as compared to the ones deposited in the normal geometry. We attribute this improvement in the overall quality of the ZnSe layers in the off-axis geometry to the reduction in the average energy of the plume particles that reach the GaAs substrate in the off-axis geometry. [Copyright &y& Elsevier]

The rapid increase in antimicrobial resistance (AMR) projects a "global emergency" and necessitates a need to discover alternative resources for combating drug-resistant pathogens or "superbugs." One of the key themes in "One Health Concept" is based on the fact that the interconnected network of humans, the environment, and animal habitats majorly contribute to the rapid selection and spread of AMR. Moreover, the injudicious and overuse of antibiotics in healthcare, the environment, and associated disciplines, further aggravates the concern. The prevalence and persistence of AMR contribute to the global economic burden and are constantly witnessing an upsurge due to fewer therapeutic options, rising mortality statistics, and expensive healthcare. The present decade has witnessed the extensive exploration and utilization of bio-based resources in harnessing antibiotics of potential efficacies. The discovery and characterization of diverse chemical entities from endophytes as potent antimicrobials define an important yet less-explored area in natural product-mediated drug discovery. Endophytes-produced antimicrobials show potent efficacies in targeting microbial pathogens and synthetic biology (SB) mediated engineering of endophytes for yield enhancement, forms a prospective area of research. In keeping with the urgent requirements for new/novel antibiotics and growing concerns about pathogenic microbes and AMR, this paper comprehensively reviews emerging trends, prospects, and challenges of antimicrobials from endophytes and their effective production via SB. This literature review would serve as the platform for further exploration of novel bioactive entities from biological organisms as "novel therapeutics" to address AMR.

The present era has witnessed an unprecedented scenario with extreme climate changes, depleting natural resources and rising global food demands and its widespread societal impact. From providing bio-based resources to fulfilling socio-economic necessities, tackling environmental challenges, and ecosystem restoration, microbes exist as integral members of the ecosystem and influence human lives. Microbes demonstrate remarkable potential to adapt and thrive in climatic variations and extreme niches and promote environmental sustainability. It is important to mention that advances in fungal biotechnologies have opened new avenues and significantly contributed to improving human lives through addressing socio-economic challenges. Microbe-based sustainable innovations would likely contribute to the United Nations sustainable development goals (SDGs) by providing affordable energy (use of agro-industrial waste by microbial conversions), reducing economic burdens/affordable living conditions (new opportunities by the creation of bio-based industries for a sustainable living), tackling climatic changes (use of sustainable alternative fuels for reducing carbon footprints), conserving marine life (production of microbe-based bioplastics for safer marine life) and poverty reduction (microbial products), among other microbe-mediated approaches. The article highlights the emerging trends and future directions into how fungal biotechnologies can provide feasible and sustainable solutions to achieve SDGs and address global issues.

Background Transdermal nitroglycerin (NTG) is a potent smooth muscle relaxant acting as a tocolytic agent by acting on the uterine muscles. The transdermal patch allows for continuous and controlled release of NTG through the skin into the bloodstream. This method offers the advantage of sustained drug delivery over a prolonged period. Objective of the study The study aimed to evaluate the efficacy of NTG patches for the arrest of preterm labor. Materials and methods This retrospective study comprised 100 patients admitted to our tertiary care center, ranging from 27 to 35 weeks of gestation, exhibiting preterm labor, uterine contractions, effacement, and dilatation of the cervix, without comorbidities and complications. Results In this study, it was observed that the incidence of preterm labor was higher among women aged 21-25 years. Pregnancy duration was extended by an average of approximately 28.63 days in our study cohort, with 90% of patients experiencing a prolongation of pregnancy to 48 hours after the application of a transdermal NTG patch. Parity distribution showed 50% of patients having a parity of G2-G4 and 30% being primigravida. However, 40% of the participants reported experiencing side effects, including headaches (15%) and local reactions (25%), while 60% did not experience any adverse effects. Conclusion In this study we found that the application of transdermal NTG patches led to a mean prolongation of pregnancy by 28.63 days, allowing time for the administration of steroids and fetal maturation. The inhibition of preterm contractions was successful, with an efficacy rate of 92%. These findings suggest the potential effectiveness of transdermal NTG patches as a tocolytic agent in managing preterm labor. However, the occurrence of side effects highlights the importance of careful monitoring and management during treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Gaikwad et al.)

Plant-microbe associations define a key interaction and have significant ecological and biotechnological perspectives. In recent times, plant-associated microbes from extreme environments have been extensively explored for their multifaceted benefits to plants and the environment, thereby gaining momentum in global research. Plant-associated extremophiles highlight ubiquitous occurrences, inhabiting extreme habitats and exhibiting enormous diversity. The remarkable capacity of extremophiles to exist in extreme environmental conditions is attributed to the evolution of adaptive mechanisms in these microbes at genetic and physiological levels. In addition, the plant-associated extremophiles have a major impact in promoting plant growth and development and conferring stress tolerance to the host plant, thereby contributing immensely to plant adaptation and survival in extreme conditions. Considering the major impact of plant-associated extremophiles from a socio-economic perspective, the article discusses their significance in emerging biotechnologies with a key focus on their ecological role and dynamic interaction with plants. Through this article, the authors aim to discuss and understand the favorable impact and dynamics of plant-associated extremophiles and their biotechnological utilities.

The increased prevalence of antibiotic resistance is alarming and has a significant impact on the economies of emerging and underdeveloped nations. The redundancy of antibiotic discovery platforms (ADPs) and injudicious use of conventional antibiotics has severely impacted millions, across the globe. Potent antimicrobials from biological sources have been extensively explored as a ray of hope to counter the growing menace of antibiotic resistance in the population. Antimicrobial peptides (AMPs) are gaining momentum as powerful antimicrobial therapies to combat drug-resistant bacterial strains. The tremendous therapeutic potential of natural and synthesized AMPs as novel and potent antimicrobials is highlighted by their unique mode of action, as exemplified by multiple research initiatives. Recent advances and developments in antimicrobial discovery and research have increased our understanding of the structure, characteristics, and function of AMPs; nevertheless, knowledge gaps still need to be addressed before these therapeutic options can be fully exploited. This thematic article provides a comprehensive insight into the potential of AMPs as potent arsenals to counter drug-resistant pathogens, a historical overview and recent advances, and their efficient production in plants, defining novel upcoming trends in drug discovery and research. The advances in synthetic biology and plant-based expression systems for AMP production have defined new paradigms in the efficient production of potent antimicrobials in plant systems, a prospective approach to countering drug-resistant pathogens.

Objective: This study aims to understand plant-bacteria interactions that enhance plant resistance to environmental stressors, with a focus on maize ( Zea mays L.) and its vulnerability to various pathogenic organisms. We examine the potential of 1-amino-cyclopropane-1-carboxylic acid (ACCA) as a compound to boost maize's resilience against stressors and pathogens., Background: With the growing global population and increased food demand, the study of endophytes, comprising bacteria and fungi, becomes crucial. They reside within plant tissues, affecting their hosts either beneficially or detrimentally. Agrobacteria are of specific interest due to their potential to contribute to developing strategies for plant resistance enhancement., Methods: We conducted exhaustive research on the defense-related proteins and mechanisms involved in maize-pathogen interactions. The efficacy of ACCA as a natural-compound that could enhance maize's resistance was examined., Results: Our research indicates that ACCA, having a binding energy of -9.98 kcal/mol, successfully strengthens maize resistance against pathogenic assaults and drought stress. It plays a crucial protective role in maize plants as they mature, outperforming other ligands in its effectiveness to improve productivity and increase yield., Conclusion: Applying ACCA to maize plants has considerable potential in enhancing their resilience and tolerance to stress, proving to be an effective strategy to boost crop yield and productivity. This could help address the increasing global food demand. However, more research is needed to optimize ACCA application methods and to gain a comprehensive understanding of its long-term effects on maize cultivations and the environment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Debnath, Elgorban, Bahkali, Eswaramoorthy, Verma, Tiwari, Wang, Wong and Syed.)

Nitrification inhibitors are recognized as a key approach that decreases the denitrification process to inhibit the loss of nitrogen to the atmosphere in the form of N 2 O. Targeting denitrification microbes directly could be one of the mitigation approaches. However, minimal attempts have been devoted towards the development of denitrification inhibitors. In this study, we aimed to investigate the molecular docking behavior of the nitrous oxide reductase (N 2 OR) and nitrite reductase (NIR) involved in the microbial denitrification pathway. Specifically, in silico screening was performed to detect the inhibitors of nitrous oxide reductase (N 2 OR) and nitrite reductase (NIR) using the PatchDock tool. Additionally, a toxicity analysis based on insecticide-likeness, Bee-Tox screening, and a STITCH analysis were performed using the SwissADME, Bee-Tox, and pkCSM free online servers, respectively. Among the twenty-two compounds tested, nine ligands were predicted to comply well with the TICE rule. Furthermore, the Bee-Tox screening revealed that none of the selected 22 ligands exhibited toxicity on honey bees. The STITCH analysis showed that two ligands, namely procyanidin B2 and thiocyanate, have interactions with both the Paracoccus denitrificans and Hyphomicrobium denitrificans microbial proteins. The molecular docking results indicated that ammonia exhibited the second least atomic contact energy (ACE) of -15.83 kcal/mol with Paracoccus denitrificans nitrous oxide reductase (N 2 OR) and an ACE of -15.20 kcal/mol with Hyphomicrobium denitrificans nitrite reductase (NIR). The inhibition of both the target enzymes (N 2 OR and NIR) supports the view of a low denitrification property and suggests the potential future applications of natural/synthetic compounds as significant nitrification inhibitors.

Substantial progress has been achieved and knowledge gaps addressed in synthetic biology-mediated engineering of biological organisms to produce high-value metabolites. Bio-based products from fungi are extensively explored in the present era, attributed to their emerging importance in the industrial sector, healthcare, and food applications. The edible group of fungi and multiple fungal strains defines attractive biological resources for high-value metabolites comprising food additives, pigments, dyes, industrial chemicals, and antibiotics, including other compounds. In this direction, synthetic biology-mediated genetic chassis of fungal strains to enhance/add value to novel chemical entities of biological origin is opening new avenues in fungal biotechnology. While substantial success has been achieved in the genetic manipulation of economically viable fungi (including Saccharomyces cerevisiae ) in the production of metabolites of socio-economic relevance, knowledge gaps/obstacles in fungal biology and engineering need to be remedied for complete exploitation of valuable fungal strains. Herein, the thematic article discusses the novel attributes of bio-based products from fungi and the creation of high-value engineered fungal strains to promote yield, bio-functionality, and value-addition of the metabolites of socio-economic value. Efforts have been made to discuss the existing limitations in fungal chassis and how the advances in synthetic biology provide a plausible solution.

Plant microbiomes represent dynamic entities, influenced by the environmental stimuli and stresses in the surrounding conditions. Studies have suggested the benefits of commensal microbes in improving the overall fitness of plants, besides beneficial effects on plant adaptability and survival in challenging environmental conditions. The concept of 'Defense biome' has been proposed to include the plant-associated microbes that increase in response to plant stress and which need to be further explored for their role in plant fitness. Plant-associated endophytes are the emerging candidates, playing a pivotal role in plant growth, adaptability to challenging environmental conditions, and productivity, as well as showing tolerance to biotic and abiotic stresses. In this article, efforts have been made to discuss and understand the implications of stress-induced changes in plant endophytic microbiome, providing key insights into the effects of heavy metals on plant endophytic dynamics and how these beneficial microbes provide a prospective solution in the tolerance and mitigation of heavy metal in contaminated sites.

Diverse forms of plant-microbe associations affect agriculture and the environment. Both plants and microbes have evolved to produce a variety of proteins and metabolites to enable or modulate their interaction with other organisms and modify their surrounding environments. Some such high-value metabolites produced by endophytes have been widely used as pharmaceutical agents and for socio-economic applications. Rapid advances in genomics have enabled the elucidation of the biology and ecology of endophytes, including their metabolic potential, by deciphering their genomic blueprints and investigating how they perform specific functions in various environmental and ecological contexts. Herein, we review recent advances in understanding the biology and ecology of endophytes and how this understanding has been harnessed to support agricultural sustainability, improve environmental health, and produce new metabolites of therapeutic significance. Genetic engineering of endophytes, guided by an enhanced understanding of their biology and advances in gene manipulation tools, promises to facilitate the production of "value-added" metabolites and the application of endophytes to solve agricultural and environmental problems. However, several knowledge deficiencies in endophyte biology should be remedied to realize their maximum potential., Competing Interests: Competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Catharanthus roseus synthesizes bioactive therapeutic metabolites, known as monoterpenoid indole alkaloids (MIAs), including antineoplastic vinblastine and vincristine, which have high global demand, and antihypertensive ajmalicine, a serpentine. However, the in planta biosynthesis and accumulation of these phytopharmaceuticals are very low, attributed to their high cytotoxicity in the plant. Considering the low in planta concentration and over-harvesting of plant resources, biotechnological interventions have been undertaken to enhance the production of MIAs in plant systems. The present study was carried out to mutation through chemical and physical mutagenesis with sodium azide, ethyl methane sulfonate and X-rays, respectively, on C. roseus to determine their possible effects on the transcriptional modulation of MIA biosynthetic pathways in planta. The chemical mutagenesis resulted in delayed seed pod development in mutated C. roseus plants, with distinct leaf morphology and flower color. However, X-ray mutagenesis resulted in pollen-less sterile flowers. An HPLC analysis confirmed the higher catharanthine, vindoline and vinblastine content in sodium azide and X-ray mutants, and was further supported by higher PRX1 transcript levels estimated through real-time PCR analysis. The transcription factors WRKY1 and ORCA2 were found negatively regulated along with major MIA pathway genes in chemical mutants and their M 1 generation, but showed positive regulation in X-ray M 0 mutants. The induced mutagenesis of C. roseus provides a prospective strategy to modulate plant transcriptomes and enhance the biosynthesis of pharmaceutically important antineoplastic vinblastine in the plant.

This report describes a case of a young man with DiGeorge Syndrome, repaired Tetralogy of Fallot, relapsed metastatic Hodgkin's Lymphoma, immunodeficiency, and a history of recurrent and severe infections. A review of the literature indicates that patients with DiGeorge Syndrome are at greater risk for infection, malignancy, and cardiac events due to anatomic and immunologic complications resulting from a deletion in the 22q11.2 chromosome. As an increased number of patients with DiGeorge Syndrome are surviving into adulthood, it is important to understand the progression of the disease and the long-term implications associated with variable degrees of thymic hypoplasia and immune deficiency., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Hare et al.)

Catharanthus roseus (Madagascar periwinkle), a medicinal plant possessing high pharmacological attributes, is widely recognized for the biosynthesis of anticancer monoterpenoid indole alkaloids (MIAs) - vinblastine and vincristine. The plant is known to biosynthesize more than 130 different bioactive MIAs, highly acclaimed in traditional and modern medicinal therapies. The MIA biosynthesis is strictly regulated at developmental and spatial-temporal stages and requires a well-defined cellular and sub-cellular compartmentation for completion of the entire MIAs biosynthesis. However, due to their cytotoxic nature, the production of vinblastine and vincristine occurs in low concentrations in planta and the absence of chemical synthesis alternatives projects a huge gap in demand and supply, leading to high market price. With research investigations spanning more than four decades, plant tissue culture and metabolic engineering (ME)-based studies were attempted to explore, understand, explain, improve and enhance the MIA biosynthesis using homologous and heterologous systems. Presently, metabolic engineering and synthetic biology are the two powerful tools that are contributing majorly in elucidating MIA biosynthesis. This review concentrates mainly on the efforts made through metabolic engineering of MIAs in heterologous microbial factories. KEY POINTS: • Yeast engineering provides alternative production source of phytomolecules • Yeast engineering also helps to discover missing plant pathway enzymes and genes., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Plant-associated endophytes define an important symbiotic association in nature and are established bio-reservoirs of plant-derived natural products. Endophytes colonize the internal tissues of a plant without causing any disease symptoms or apparent changes. Recently, there has been a growing interest in endophytes because of their beneficial effects on the production of novel metabolites of pharmacological significance. Studies have highlighted the socio-economic implications of endophytic fungi in agriculture, medicine, and the environment, with considerable success. Endophytic fungi-mediated biosynthesis of well-known metabolites includes taxol from Taxomyces andreanae , azadirachtin A and B from Eupenicillium parvum , vincristine from Fusarium oxysporum , and quinine from Phomopsis sp. The discovery of the billion-dollar anticancer drug taxol was a landmark in endophyte biology/research and established new paradigms for the metabolic potential of plant-associated endophytes. In addition, endophytic fungi have emerged as potential prolific producers of antimicrobials, antiseptics, and antibiotics of plant origin. Although extensively studied as a "production platform" of novel pharmacological metabolites, the molecular mechanisms of plant-endophyte dynamics remain less understood/explored for their efficient utilization in drug discovery. The emerging trends in endophytic fungi-mediated biosynthesis of novel bioactive metabolites, success stories of key pharmacological metabolites, strategies to overcome the existing challenges in endophyte biology, and future direction in endophytic fungi-based drug discovery forms the underlying theme of this article.

Herein, we report the theoretical investigation on the photonic nanojets (PNJs) of single dielectric microspheres illuminated by focused broadband radiation (polychromatic light) from a Halogen lamp, supercontinuum source, light-emitting diode, and Hg arc lamp. The role of incident beam waist, refractive index of the surrounding medium, and radius of the microsphere on the characteristic parameters such as the electric field intensity enhancement, effective width, and length of the PNJ is studied. Interestingly, the characteristic parameters of the PNJs of solid microspheres obtained for the above-mentioned broadband radiation sources are found close to those observed for the focused monochromatic radiation of wavelengths which are near to the central wavelengths of the sources. Moreover, the characteristic parameters of PNJs of the core-shell microspheres of different thicknesses (t) illuminated by polychromatic radiation from most commonly used sources such as Halogen and Hg arc lamps are studied. For each t value, a suitable wavelength of monochromatic radiation has been found to generate the PNJ with characteristic parameters which are close to those obtained in the case of polychromatic radiation. We believe that the analytical theory and the theoretical simulations reported here would be useful for researchers who work in the fields such as PNJ assisted photoacoustic spectroscopy, white light nanoscopy, low-coherence phase-shifting interference microscopy, and Mirau interferometry., (© 2022. The Author(s).)