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1.
Dalton Trans ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291455

RESUMO

Understanding the lattice thermal conductivity (κl) of ß-Ga2O3 is very intriguing owing to its advantages in high-voltage and high-temperature applications. Despite several attempts, the underlying mechanism and causes of the notable discrepancies found in the κl values of ß-Ga2O3 along [100] and [001] directions calculated using first principles remained unresolved. We demonstrate that the understanding of the nature of chemical bonding is crucial to overcome the inconsistency in theoretically reported κl values. In low-symmetry structures such as ß-Ga2O3, the nature of the interactions is primarily long-range; therefore, a sufficiently large supercell inclusive of various bonding characteristics is required to capture relevant phonon wavelengths. Bonding nature-aware structure modeling allows precise estimation of acoustic and optical mode contributions towards κl. Additionally, phonon mean free path analysis confirms that considering only third-order interaction terms is adequate to determine the κl of ß-Ga2O3. The calculated κl values are in excellent agreement with experimentally reported values in all three directions. Our results establish that the bonding nature and its influence on phonon scattering are essential to consider in calculating κl accurately.

2.
Sci Rep ; 14(1): 21270, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261516

RESUMO

Electrolysis of D2O may be used as a portable neutron source with numerous applications without the complexity of huge reactor operations. Herein, we report reproducible fast neutron generation by electrolysis of D2O using palladium cathode and platinum anode, which was detected with diamond detector, gas filled 3He detectors after thermalisation with high density polythene, as well as novel epoxy resin and CR-39 detectors. Notably, a highly reproducible neutron generation at electrochemical surfaces of palladium electrode was observed and signature transmutation via Pd (d, n) Ag was corroborated. This was further explained using a theoretical model based on second order quantum perturbation theory.

3.
Inorg Chem ; 63(36): 16585-16589, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39185779

RESUMO

The present work envisages a chelation driven, facile, selective, and rapid method for uranium(VI) separation from a (U, Th) mixture using 1-hydroxy-2-pyridone (1,2-HOPO). Herein, U(VI) was selectively precipitated as the neutral [UO2(HOPO)2(H2O)]·nH2O (orange colored) complex while Th(IV) and other metal ions remained in the solution. The pH of the medium played a key role in facilitating the separation process.

4.
Anal Chem ; 96(37): 14891-14901, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39215686

RESUMO

The destructive assay of bulk uranium and plutonium, a cornerstone for chemical quality control and nuclear material accounting of fuel matrices, mandates robust and precise methodologies. Despite ongoing research, simultaneous, matrix independent determination of U and Pu has eluded solution owing to inherent limitations in aqueous acid medium, viz., coexistence of multiple oxidation states, coupled electrochemical reactions, smaller potential window, and requirement for multistep sample preconditioning and tedious electrode modification. The present study addresses this challenge wherein non-aqueous methanesulfonic acid (MSA) served the dual role of solvent and analyte media with a bare glassy carbon (GC) electrode. Fuel matrices, viz., (U, Pu)C, (U, Pu)O2, PuO2, UO3, UO2, and U3O8, were quantitatively dissolved in biodegradable MSA, without using any additives. Redox speciation of the analytes, U and Pu, in MSA was probed by ultraviolet-visible spectrophotometry and electrometry, revealing the absence of electrocatalytic regeneration and stabilization of single oxidation state, viz., U(VI) and Pu(IV), along with relevant redox-energetic (electron transfer and reversibility) and kinetic data. Bidentate coordination of MSA with the U analyte was indicated by X-ray absorption spectroscopy studies and was corroborated by density functional theory-based investigations, providing the optimized structure, viz., [UO2(MSA)2] and [Pu(MSA)4], binding modes and energy, partial charges, and molecular orbital diagrams. Based on these insights, the feasibility of differential pulse voltammetry (DPV)-based assay method development for U and Pu separately and in different U/Pu ratios, representing assorted fuel matrices, was probed. Analytical figures of merit for both U and Pu (detection limit of ∼10-5 M, precision of ∼0.2%, accuracy of ∼0.2%, high sensitivity, repeatability, and non-influence of relevant interferences) were determined, method validated employing actual fuel samples, and compared with the established, multi-step biamperometry method. Hence, a universal, simultaneous U and Pu destructive assay method in non-aqueous MSA media based on DPV with a commercial GC electrode was demonstrated.

5.
J Biol Chem ; 300(9): 107650, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39122002

RESUMO

Antimicrobial resistance (AMR) is a serious global threat demanding innovations for effective control of pathogens. The bacterial SOS response, regulated by the master regulators, LexA and RecA, contributes to AMR through advantageous mutations. Targeting the LexA/RecA system with a novel inhibitor could suppress the SOS response and potentially reduce the occurrence of AMR. RecA presents a challenge as a therapeutic target due to its conserved structure and function across species, including humans. Conversely, LexA which is absent in eukaryotes, can be potentially targeted, due to its involvement in SOS response which is majorly responsible for adaptive mutagenesis and AMR. Our studies combining bioinformatic, biochemical, biophysical, molecular, and cell-based assays present a unique inhibitor of mycobacterial LexA, wherein we show that the inhibitor interacts directly with the catalytic site residues of LexA of Mycobacterium tuberculosis (Mtb), consequently hindering its cleavage, suppressing SOS response thereby reducing mutation frequency and AMR.

6.
Plant Mol Biol ; 114(5): 93, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39207587

RESUMO

Most organisms have evolved specific mechanisms to respond to changes in environmental conditions such as light and temperature over the course of day. These periodic changes in the physiology and behaviour of organisms, referred to as circadian rhythms, are a consequence of intricate molecular mechanisms in the form of transcription and translational feedback loops. The plant circadian regulatory network is a complex web of interconnected feedback loops involving various transcription factors such as CCA1, LHY, PRRs, TOC1, LUX, ELF3, ELF4, RVE8, and more. This network enables plants to adapt and thrive in diverse environmental conditions. It responds to entrainment signals, including light, temperature, and nutrient concentrations and interacts with most of the physiological functions such as flowering, growth and stress response. Mathematical modelling of these gene regulatory networks enables a deeper understanding of not only the function but also the perturbations that may affect the plant growth and function with changing climate. Over the years, numerous mathematical models have been developed to understand the diverse aspects of plant circadian regulation. In this review, we have delved into the systematic development of these models, outlining the model components and refinements over time. We have also highlighted strengths and limitations of each of the models developed so far. Finally, we conclude the review by describing the prospects for investigation and advancement of these models for better understanding of plant circadian regulation.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Redes Reguladoras de Genes , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Relógios Circadianos/genética , Regulação da Expressão Gênica de Plantas , Modelos Teóricos , Plantas/genética , Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Modelos Biológicos
7.
Gene ; 927: 148671, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38866260

RESUMO

The Batagur kachuga (B. kachuga), commonly known as the Red-crowned roofed turtle, is a critically endangered species native to India and its neighboring countries like Bangladesh, and Nepal. The present study is the first report of the complete mitochondrial genome of B. kachuga (16,517 bp) construed via the next-generation sequencing (NGS) approach from eggshell DNA. There are 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), 13 protein-coding genes (PCGs), and one putative control region (CR/D-loop) in the mitogenome. The CR region from the current study reveals conserved TAS, CD, and CSB domains and two AT-rich tandem repeat regions. Most genes are encoded in the heavy strand except the NADH dehydrogenase subunit 6 (ND6) gene and seven tRNA genes. Most PCGs start with the initiation codon ATG, except the COI (Cytochrome Oxidase Subunit-I) gene, which starts with the GTG codon. The present investigation also predicts the distinctive cloverleaf structures of tRNAs except for tRNA-Ser1 and tRNA-Ser-2, which lack a DHU arm. The comparative analysis of Ka/Ks with other 33 species from Order Testudines, in relation to B. kachuga, revealed negative selection in most PCGs, indicating a process of preservation and purification that aids in eliminating undesirable or detrimental substitutes. Phylogenetic analysis of this species has been analysed using the complete mitogenome of 33 turtle species. The maximum likelihood phylogenetic tree strongly supports each family in different clades and also reveals a close relationship between the Pangashura and Batagur genera. Our study suggests the generation of genome-wide molecular data, in terms of mitogenomes, SNPs, and SSRs, is needed to improve the understanding of this species and their phylogenetics and evolutionary relationships, which will help to improve the conservation efforts of this species.


Assuntos
Espécies em Perigo de Extinção , Evolução Molecular , Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , RNA de Transferência , Tartarugas , Animais , Tartarugas/genética , Tartarugas/classificação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA de Transferência/genética , RNA Ribossômico/genética
8.
J Mol Model ; 30(5): 154, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691236

RESUMO

CONTEXT: Density functional theory (DFT) calculations are carried out on pure and doped rutile TiO 2 . The bandgap (E g ) for pristine, S-doped, Fe-doped, and Fe/S co-doped materials is direct, with values of 2.98 eV, 2.18 eV, 1.58 eV, and 1.40 eV. The effective mass of charge carriers (m*) and ratio of effective masses of holes to effective masses of electrons (R) are also investigated, and it is discovered that Fe/S co-doped materials have the lowest charge carrier recombination rate. The Fe/S co-doped material has the highest ε ( ω ) . α ( ω ) of doped materials shifted into the visible range. Due to the high dopant concentration in Fe and Fe/S-doped cases, the E g is lowered to a relatively small value; hence, only pristine and S-doped materials are verified as electron transport layer (ETL). A solar cell device analysis employing pure and S-doped rutile TiO 2 as ETL is completed using DFT-derived parameters in SCAPS-1D modeling software for the first time. For the optimized solar cells, current-voltage (IV) characteristics, quantum efficiency (QE), capacitance-voltage (CV) characteristics, and capacitance-frequency (Cf) characteristics are provided. The aim of the present study is to improve efficiency of perovskite solar cell by doping as well as to improve accuracy of simulation by applying DFT extracted parameters as input. From the analysis, improvement is found in efficiency of doped TiO 2 compared to un-doped TiO 2 . The efficiency of the PSC with S-doped ETL is 1.418% higher than the PSC with un-doped ETL. METHOD: Quantumwise Automistic Tool Kit (ATK) is used to extract DFT parameters. Using these DFT parameters as input in SCAPS-1D (Solar Cell Capacitance Simulator), solar cells for doped and un-doped material are simulated. The density functional theory (DFT)-based orthogonalized linear combination of atomic orbital (OLCAO) technique is used. Structural optimization is done using the LBFGS (Limited-memory Broyden-Fletcher-Goldfarb-Shanno). PBESol-GGA (Perdew-Burke-Ernzerhof solid-generalized gradient approximation) is applied as exchange correlation for calculating structural parameters, while MGGA-TB09 (meta-generalized gradient approximation-Tran and Blaha) is applied as exchange correlation for calculating optical and electronic properties.

9.
Inorg Chem ; 63(16): 7161-7176, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38591969

RESUMO

A quantitative, rapid, endothermic dissolution of U3O8 in C4mim·PF6 (1-alkyl-3-methyl imidazolium hexafluorophosphate) has been achieved within 2 h at 65 °C by in situ generated fluoride ions by pre-equilibrating the ionic liquid with suitable concentrations of nitric acid. The efficiency of the dissolution followed the trend: UO3 > UO2 > U3O8. The fluoride generation was found to increase with the concentration of nitric acid being equilibrated, the water content of the ionic liquid, and also the time of equilibration. The rate of dissolution of U3O8 followed the trend: C4mim·PF6> C6mim·PF6 > C8mim·PF6. The maximum loading observed for the present case was 200 mg mL-1 which is considered to be quite high with an ionic liquid. The effects of different acid pre-equilibration (HClO4, HCl) on F- generation and subsequent dissolution characteristics have also been investigated. The in situ F- generation, as well as U3O8 dissolution, were found to predominantly follow a pseudo-second-order rate kinetics, while the rate constants for U3O8 dissolution were found to be higher than that of F- generation. The dissolved uranium was successfully electrodeposited on a Cu plate, as confirmed by EDXRF, while the formation of UO2 was revealed from the XRD pattern of the deposit.

10.
Dalton Trans ; 53(17): 7321-7339, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591248

RESUMO

The +5 state is an unusual oxidation state of uranium due to its instability in the aqueous phase. As a result, gaining information about its aqueous speciation is extremely difficult. The present work is an attempt in that direction and it provides insight into the existence of a new pentavalent species in the presence of hetero-bifunctional phosphonocarboxylate (PC) chelators, other than the carbonate ion, in the aqueous medium. The aqueous chemistry of pentavalent uranium species with three environmentally relevant PCs was probed using electrochemical and DFT methods to understand the redox energy and kinetics of conversion of the U(VI)/U(V) couple, stability, structure, stoichiometry, binding modes, etc. Interestingly, pentavalent uranium complexes with PCs are quite persistent over a wide range of pH starting from acidic to alkaline conditions. The PC chelators block the cation-cation interaction (CCI) of U(V) through strong hetero-bidentate chelation and intermolecular hydrogen bonding (IMHB) interactions which stabilize the pentavalent metal ion against disproportionation. For uranyl species in the presence of PCs, acting as chelators, CV plots were obtained at varying pH values from 2 to 8. The obtained results indicate an irreversible single redox peak involving U(VI) to U(V) conversion and association of a coupled chemical reaction with the electron transfer step. ESI-MS studies were performed to understand the speciation effect on the U(VI)/U(V) redox couple with varying pH. Speciation modelling of U(V) with the PC ligands was carried out, which indicated that the U(V) is redox stable in nearly 47% of the pH region in the presence of the PCs as compared to the carboxylate-based chelators. The free energy and reduction potential of the U(V) complexes and the reduction free energy and disproportionation free energy for the U(VI)/U(V) couple were determined by DFT computations in the presence of the PCs. In situ spectroelectrochemical spectra were recorded to provide evidence for the existence of U(V) species with PCs in the aqueous medium and to acquire its absorption spectra. The present study is highly significant for understanding the coordination chemistry of pentavalent uranium species, accurate modelling of uranium, and isolation of U(V).

11.
iScience ; 27(3): 109286, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38482489

RESUMO

Protein-coated microbubbles have become one of the emerging platforms in biomedical research as theranostic agents. In recent years, microbubbles have been extensively used as ultrasound contrast agents and carriers of molecular cargoes, pertaining to which several studies have focused on tuning the properties of these bubbles to achieve a higher degree of biocompatibility and extended stability. Synthesis of microbubbles has so far been traditionally carried out with pre-heated proteins like bovine serum albumin (BSA) as shell coatings, owing to the ease in making BSA crosslinked structures through disulfide bridge formation. We, however, have performed experiments to demonstrate that air core microbubbles formed with native BSA are more stable compared with those formed using denatured BSA. The experimental observations have been supported with analytical modeling and computational studies, which offer insights into the effect of BSA conformation in stabilizing the microbubbles shells and prolonging their lifetimes.

12.
Inorg Chem ; 63(5): 2533-2552, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38272469

RESUMO

A multitechnique approach with theoretical insights has been employed to understand the complexation of trivalent lanthanides with two ß-diketones, viz. 1-phenyl-1,3-butanedione (L1) and 4,4,4-trifluoro-1-phenyl-1,3-butanedione (L2), in an ionic liquid (C6mim·NTf2). UV-vis spectral analysis of complexation using Nd3+ revealed the predominance of ML2+ and ML4- species. The stability constants for the PB complexes were higher (ß2 ∼ 10.45 ± 0.05, ß4 ∼ 15.51 ± 0.05) than those for the TPB (ß2 ∼ 7.56 ± 0.05, ß4 ∼ 13.19 ± 0.06). The photoluminescence titration using Eu3+ corroborated the same observations with slightly higher stability constants, probably due to the higher ionic potential of Eu3+. The more asymmetric (AL2ML4 ∼ 5.2) Eu-L2 complex was found to contain one water molecule in the primary coordination sphere of Eu3+ with more covalency of the Eu3+-O bond (Ω2L1 = 8.5 × 10-20, Ω4L1 = 1.3 × 10-20) compared to the less asymmetric Eu-L1 complex (AL1ML4 ∼ 3.5) with two water molecules having less Eu-O covalency (Judd-Offelt parameters: Ω2L1 = 7.3 × 10-20, Ω4L1 = 1.0 × 10-20). Liquid-liquid extraction studies involving Nd3+ and Eu3+ revealed the formation of the ML4- complex following an 'anion exchange' mechanism. The shift of the enol peak from 1176 to 1138 cm-1 on the complexation of the ß-diketones with Eu3+ was confirmed from the FTIR spectra. 1H NMR titration of the ß-diketones with La(NTf2)3 evidenced the participation of α-H of the ß-diketones and protons at C2, C4, and C5 positions of the methylimidazolium ring. For the ML2 complex, 4 donor O atoms are suggested to coordinate to the trivalent lanthanides with bond distances of 2.3297-2.411 Å for La-O, 2.206-2.236 Å for Eu-O, and 2.217-2.268 Å for Nd-O, respectively, while for the ML4 complex, 8 donor O atoms were coordinated with bond lengths of 2.506-2.559 Å for La-O, 2.367-2.447 Å for Eu-O, and 2.408-2.476 Å for Nd-O. The Nd3+ ion was higher by 9.7 kcal·mol-1 than that of the La3+ ion for the 1:4 complex. The complexation energy with L1 was quite higher than that with L2 for both 1:2 and 1:4 complexes. Using cyclic voltammetry, the redox behavior of trivalent lanthanides Eu and Gd with ß-diketonate in ionic liquid medium was probed and their redox energetic and kinetic parameters were determined.

13.
J Biosci ; 472022.
Artigo em Inglês | MEDLINE | ID: mdl-36222127

RESUMO

Network theory has led to the abstraction of many real-world systems and enabled their modelling as simple networks comprising nodes and edges. In particular, in the field of biological sciences, network theory provides a robust framework to capture the complexity inherent to biological systems. Networks in biology have been modelled at different scales, starting from cells to population levels. These models have provided crucial insights into the evolution, mechanism, and functions of several biological systems. However, most natural and engineered systems are composed of multiple subsystems and layers of connectivity. A multilayer network paradigm has proven useful in understanding such systems. Here, we have briefly introduced the network formalism of modelling biological systems at various levels. This is followed by an introduction to multilayer networks. Multilayer networks have been utilized to model biological systems at multiple scales ranging from protein-protein interactions, transcription and metabolic networks, to ecological networks involving interactions between species. Recent advances in studying the structure and dynamics of such multilayer networks have enabled a better understanding of the complexity in these biological systems. Finally, we discuss the recent advances in studying the structure and dynamics of such multilayered networks followed by the challenges and future prospects.


Assuntos
Redes e Vias Metabólicas , Modelos Biológicos , Comunicação Celular , Redes e Vias Metabólicas/genética
14.
Inorg Chem ; 61(39): 15452-15462, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36123167

RESUMO

Carbon and phosphorous are two primary elements common to the bio-geosphere and are omnipresent in both biotic and abiotic arenas. Phosphonate and carboxylate are considered as building blocks of glyphosate and humic substances and constituents of the cellular wall of bacteria and are the driving functionalities for most of the chemical interactions involving these two elements. Phosphonocarboxylates, a combination of both the functionalities in one moiety, are ideal models to dig deep into for understanding the chemical interactions of the two functional groups with metal ions. Phosphorous and carbon majorly exist as inorganic/organic phosphate and carboxylate, respectively, in the bio-geosphere. Aquatic contamination is a major concern for uranium, and the presence of complexing agents would alter the uranium concentrations in aquifers. Determination of solution thermodynamic parameters, speciation plots, redox patterns, Eh-pH diagrams, coordination structures, and molecular-level understanding by density functional theory calculations was carried out to interpret the uranyl (UO22+) interaction with three environmentally relevant phosphonocarboxylates, namely, phosphono-formic acid (PFA), phosphono-acetic acid (PAA), and phosphono-propanoic acid (PPA). UO22+ forms 1:1 complexes with the three phosphonocarboxylates in the monoprotonated form, having nearly the same stability, and the complexes [UO2(PFAH)], [UO2(PAAH)], and [UO2(PPAH)] involve chelate formation of five, six, and seven membered rings, respectively, through the participation of an oxygen each from the carboxylate and phosphonate, strengthened by an intra-molecular hydrogen bonding through the proton of the phosphonate moiety with uranyl oxygen. The complex formations are favored both enthalpically and entropically, with the latter being more contributive to the overall free energy of formation. The redox speciation showed an aqueous soluble complex formation over a wide pH range of 1-8. Electrospray ionization mass spectrometry and extended X-ray absorption fine structure established the coordination modes, which are further corroborated by density functional calculations. The knowledge gained from the present studies provide potential inputs in framing the cleanup, sequestering, microbial, and bio-remediation strategies for uranyl from aquatic environments.


Assuntos
Organofosfonatos , Urânio , Carbono , Ácidos Carboxílicos , Substâncias Húmicas , Íons , Organofosfatos , Oxirredução , Oxigênio , Prótons , Urânio/química
15.
Angew Chem Int Ed Engl ; 61(41): e202210783, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35971950

RESUMO

Intrinsically low lattice thermal conductivity (κlat ) while maintaining the high carrier mobility (µ) is of the utmost importance for thermoelectrics. Topological insulators (TI) can possess high µ due to the metallic surface states. TIs with heavy constituents and layered structure can give rise to high anharmonicity and are expected to show low κlat . Here, we demonstrate that Bi1.1 Sb0.9 Te2 S (BSTS), which is a 3D bulk TI, exhibits ultra-low κlat of 0.46 Wm-1 K-1 along with high µ of ≈401 cm2  V-1 s-1 . Sound velocity measurements and theoretical calculations suggest that chemical bonding hierarchy and high anharmonicity play a crucial role behind such ultra-low κlat . BSTS possesses low energy optical phonons which strongly couple with the heat carrying acoustic phonons leading to ultra-low κlat . Further, Cl has been doped at the S site of BSTS which increases the electron concentration and reduces the κlat resulting in a promising n-type thermoelectric figure of merit (zT) of ≈0.6 at 573 K.

16.
Int J Mol Sci ; 23(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35628143

RESUMO

Protein kinases are responsible for healthy cellular processes and signalling pathways, and their dysfunction is the basis of many pathologies. There are numerous small molecule inhibitors of protein kinases that systemically regulate dysfunctional signalling processes. However, attaining selectivity in kinase inhibition within the complex human kinome is still a challenge that inspires unconventional approaches. One of those approaches is photopharmacology, which uses light-controlled bioactive molecules to selectively activate drugs only at the intended space and time, thereby avoiding side effects outside of the irradiated area. Still, in the context of kinase inhibition, photopharmacology has thus far been rather unsuccessful in providing light-controlled drugs. Here, we present the discovery and optimisation of a photoswitchable inhibitor of casein kinase 1δ (CK1δ), important for the control of cell differentiation, circadian rhythm, DNA repair, apoptosis, and numerous other signalling processes. Varying the position at which the light-responsive azobenzene moiety has been introduced into a known CK1δ inhibitor, LH846, revealed the preferred regioisomer for efficient photo-modulation of inhibitory activity, but the photoswitchable inhibitor suffered from sub-optimal (photo)chemical properties. Replacement of the bis-phenyl azobenzene group with the arylazopyrazole moiety yielded a superior photoswitch with very high photostationary state distributions, increased solubility and a 10-fold difference in activity between irradiated and thermally adapted samples. The reasons behind those findings are explored with molecular docking and molecular dynamics simulations. Results described here show how the evaluation of privileged molecular architecture, followed by the optimisation of the photoswitchable unit, is a valuable strategy for the challenging design of the photoswitchable kinase inhibitors.


Assuntos
Caseína Quinase Idelta , Inibidores de Proteínas Quinases , Pirazóis , Apoptose/efeitos dos fármacos , Caseína Quinase Idelta/antagonistas & inibidores , Caseína Quinase Idelta/metabolismo , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia
17.
PLoS One ; 17(4): e0252173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35482775

RESUMO

East Indian Sandalwood (Santalum album L.) is highly valued for its heartwood and its oil. There have been no efforts to comparative study of high and low oil yielding genetically identical sandalwood trees grown in similar climatic condition. Thus we intend to study a genome wide transcriptome analysis to identify the corresponding genes involved in high oil biosynthesis in S. album. In this study, 15 years old S. album (SaSHc and SaSLc) genotypes were targeted for analysis to understand the contribution of genetic background on high oil biosynthesis in S. album. A total of 28,959187 and 25,598869 raw PE reads were generated by the Illumina sequencing. 2.12 million and 1.811 million coding sequences were obtained in respective accessions. Based on the GO terms, functional classification of the CDS 21262, & 18113 were assigned into 26 functional groups of three GO categories; (4,168; 3,641) for biological process (5,758;4,971) cellular component and (5,108;4,441) for molecular functions. Total 41,900 and 36,571 genes were functionally annotated and KEGG pathways of the DEGs resulted 213 metabolic pathways. In this, 14 pathways were involved in secondary metabolites biosynthesis pathway in S. album. Among 237 cytochrome families, nine groups of cytochromes were participated in high oil biosynthesis. 16,665 differentially expressed genes were commonly detected in both the accessions (SaHc and SaSLc). The results showed that 784 genes were upregulated and 339 genes were downregulated in SaHc whilst 635 upregulated 299 downregulated in SaSLc S. album. RNA-Seq results were further validated by quantitative RT-PCR. Maximum Blast hits were found to be against Vitis vinifera. From this study, we have identified additional number of cytochrome family in high oil yielding sandalwood accessions (SaHc). The accessibility of a RNA-Seq for high oil yielding sandalwood accessions will have broader associations for the conservation and selection of superior elite samples/populations for further genetic improvement program.


Assuntos
Óleos Voláteis , Santalum , Sesquiterpenos , Adolescente , Citocromos/metabolismo , Perfilação da Expressão Gênica , Humanos , Óleos Voláteis/metabolismo , Santalum/genética , Santalum/metabolismo , Sesquiterpenos/metabolismo
18.
Biotechnol Bioeng ; 119(8): 2046-2063, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35470439

RESUMO

The ocean covers two-third of our planet and has great biological heterogeneity. Marine organisms like algae, vertebrates, invertebrates, and microbes are known to provide many natural products with biological activities as well as potential sources of biomaterials for therapeutic, biomedical, biosensors, and climate stabilization. Over the years, the field of biosensors has gained huge attention due to their extraordinary ability to provide early disease diagnosis, rapid detection of various molecules and substances along with long-term monitoring. This review aims to focus on the properties and employment of various biomaterials (carbohydrate polymers, proteins, polyacids, etc.) of marine origins such as alginate, chitin, chitosan, fucoidan, carrageenan, chondroitin sulfate, hyaluronic acid, collagen, marine pigments, marine nanoparticles, hydroxyapatite, biosilica, lectins, and marine whole cell in the design and development of biosensors. Furthermore, this review also covers the source of such marine biomaterials and their promising evolution in the fabrication of biosensors that are potent to be employed in the biomedical, environmental science, and agricultural sciences domains. The use of such fabricated biosensors harnesses the system with excellent specificity, selectivity, biocompatibility, thermal stability, and minimal cost advantages.


Assuntos
Técnicas Biossensoriais , Quitosana , Animais , Organismos Aquáticos , Materiais Biocompatíveis , Quitina , Polímeros , Polissacarídeos
19.
RSC Adv ; 12(10): 6234-6247, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35424542

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) causes a highly infectious disease with reported mortality in the range 2.8% to 47%. The replication and transcription of the SFTSV genome is performed by L polymerase, which has both an RNA dependent RNA polymerase domain and an N-terminal endonuclease (endoN) domain. Due to its crucial role in the cap-snatching mechanism required for initiation of viral RNA transcription, the endoN domain is an ideal antiviral drug target. In this virtual screening study for the identification of potential inhibitors of the endoN domain of SFTSV L polymerase, we have used molecular docking and molecular dynamics (MD) simulation to explore the natural product space of 14 011 phytochemicals from Indian medicinal plants. After generating a heterogeneous ensemble of endoN domain structures reflecting conformational diversity of the corresponding active site using MD simulations, ensemble docking of the phytochemicals was performed against the endoN domain structures. Apart from the ligand binding energy from docking, our virtual screening workflow imposes additional filters such as drug-likeness, non-covalent interactions with key active site residues, toxicity and chemical similarity with other hits, to identify top 5 potential phytochemical inhibitors of endoN domain of SFTSV L polymerase. Further, the stability of the protein-ligand docked complexes for the top 5 potential inhibitors was analyzed using MD simulations. The potential phytochemical inhibitors, predicted in this study using contemporary computational methods, are expected to serve as lead molecules in future experimental studies towards development of antiviral drugs against SFTSV.

20.
PLoS One ; 17(4): e0261569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35389996

RESUMO

Brassica juncea L. is a significant member of the Brassicaceae family, also known as Indian mustard. Water is a limiting factor in the successful production of this crop. Here, we tested the effect of water shortage in B. juncea plants supplemented with or without the application of silicon and arbuscular mycorrhizal fungi in total 8 different treatments compared under open filed conditions using a randomised complete block design (RCBD). The treatments under control conditions were control (C, T1); C+Silicon (Si, T2); C+My (Mycorrhiza; T3); and C+Si+My (T4). In contrast, treatments under stress conditions were S (Stress; T5); S+Si (T6); S+My (T7) and S+Si+My (T8), respectively. In total, we evaluated 16 traits, including plant response to stress by evaluating peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activity. The fresh weight (g) increased only 7.47 percent with mycorrhiza (C+My) and 22.39 percent with silicon (C+Si) but increased 291.08 percent with both mycorrhiza and silicon (C+Si+My). Using mycorrhiza (S+My) or silicon (S+Si) alone produced a significant increase of 53.16 percent and 55.84 percent in fresh weight, respectively, while using both mycorrhiza and silicon (S+Si+My) together produced a dramatic increase of 380.71 percent under stress conditions. Superoxidase dismutase concentration (Ug-1 FW) was found to be increased by 29.48 percent, 6.71 percent, and 22.63 percent after applying C+My, C+Si and C+Si+My, but treatment under stress revealed some contrasting trends, with an increase of 11.21 percent and 19.77 percent for S+My, S+Si+My, but a decrease of 13.15 percent for S+Si. Finally, in the presence of stress, carotenoid content (mg/g FW) increased by 58.06 percent, 54.83 percent, 183.87 percent with C+My, and 23.81 percent with S+My and S+Si+My, but decreased by 22.22 percent with S+Si. Silicon application proved to be more effective than AMF treatment with Rhizophagus irregularis, and the best results were obtained with the combination of Si and AMF. This work will help to suggest the measures to overcome the water stress in B. juncea.


Assuntos
Mostardeira , Micorrizas , Antioxidantes/farmacologia , Desidratação , Micorrizas/fisiologia , Silício/farmacologia
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