627,176 results match your criteria conformation

Carvacrol, citral and α-terpineol essential oil incorporated biodegradable films for functional active packaging of Pacific white shrimp.

Food Chem 2021 May 30;363:130252. Epub 2021 May 30.

Department of Packaging and Materials Technology, Faculty of Agro-Industry, Kasetsart University, 50 Ngam Wong Wan Rd., Latyao, Chatuchak, Bangkok 10900, Thailand; Center for Advanced Studies for Agriculture and Food, Kasetsart University, 50 Ngam Wong Wan Rd., Latyao, Chatuchak, Bangkok 10900, Thailand. Electronic address:

Biodegradable poly(butylene adipate terephthalate) and poly(lactic acid) (PBAT/PLA) blend films compounded with carvacrol, citral and α-terpineol essential oils (EOs) were produced for food packaging via blown-film extrusion. PBAT/PLA interacted with citral and α-terpineol via hydrogen bonding and carbonyl groups. Microstructures and barrier properties against water vapor and oxygen were modified depending on types and concentrations (3% and 6%) of EOs. Read More

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Extracellular loops of the serotonin transporter act as a selectivity filter for drug binding.

J Biol Chem 2021 Jun 9:100863. Epub 2021 Jun 9.

The Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Austria.

The serotonin transporter (SERT) shapes serotonergic neurotransmission by retrieving its eponymous substrate from the synaptic cleft. Ligands which discriminate between SERT and its close relative, the dopamine transporter DAT, differ in their association rate constant rather than their dissociation rate. The structural basis for this phenomenon is not known. Read More

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A comprehensive review on molecular mechanism of defective dry-cured ham with excessive pastiness, adhesiveness, and bitterness by proteomics insights.

Compr Rev Food Sci Food Saf 2021 Jun 12. Epub 2021 Jun 12.

Key Laboratory of Meat Processing and Quality Control, MOE, Nanjing Agricultural University, Nanjing, P.R. China.

Excessive bitterness, pastiness, and adhesiveness are the main organoleptic and textural defects of dry-cured ham, which often cause a lot of financial losses to manufacturers and seriously damage the quality of the product. These sensory and textural defects are related to the protein degradation of dry-cured ham. Proteomics shows great potential to improve our understanding of the molecular mechanism of sensory and textural defects and identify biomarkers for monitoring their quality traits. Read More

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Crystal structure of the cofactor-free form of thioredoxin reductase from Acinetobacter baumannii.

FEBS Lett 2021 Jun 12. Epub 2021 Jun 12.

College of Pharmacy, Chung-Ang University, Seoul, 06974, Republic of Korea.

Thioredoxin reductase (TrxR) is a central component in the thioredoxin system involved in catalyzing the reduction of thioredoxin, which is critical for organism survival. Because this system is essential, it is a promising target for novel antimicrobial agents. Herein, we solved the 1. Read More

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Synthesis and Characterization of Mitochondria-Targeted Triphenylphosphonium Bolaamphiphiles.

Methods Mol Biol 2021 ;2275:27-47

CNR-ISB, Sede Secondaria di Roma-Meccanismi di Reazione c/o Department of Chemistry, Sapienza University, Roma, Italy.

In this chapter we describe: (1) the procedure for the synthesis of four single chain bolaamphiphiles, displaying chains of 12, 16, 20 and 30 methylene units and triphenylphosphonium moieties as headgroups (TPP1-TPP4); (2) the methods used to characterize TPP1-TPP4 spontaneous aggregation in aqueous solution. We illustrate the determination of Krafft point and cac by conductivity measurements and the procedures used to investigate dimensions, morphology, and stability by dynamic and dielectrophoretic laser light scattering, dialysis, transmission electron microscopy, and Raman spectroscopy measurements. Read More

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January 2021

Recent developments in engineering protein-protein interactions using phage display.

Protein Eng Des Sel 2021 Feb;34

Department of Molecular and Cellular Biology, College of Biological Science, University of Guelph, 50 Stone Rd E, Guelph, Ontario N1G2W1, Canada.

Targeted inhibition of misregulated protein-protein interactions (PPIs) has been a promising area of investigation in drug discovery and development for human diseases. However, many constraints remain, including shallow binding surfaces and dynamic conformation changes upon interaction. A particularly challenging aspect is the undesirable off-target effects caused by inherent structural similarity among the protein families. Read More

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February 2021

Bioinspired Solid-State Nanochannel Sensors: From Ionic Current Signals, Current, and Fluorescence Dual Signals to Faraday Current Signals.

Small 2021 Jun 12:e2100495. Epub 2021 Jun 12.

Cancer Centre and Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Macau, SAR, 999078, China.

Inspired from bioprotein channels of living organisms, constructing "abiotic" analogues, solid-state nanochannels, to achieve "smart" sensing towards various targets, is highly seductive. When encountered with certain stimuli, dynamic switch of terminal modified probes in terms of surface charge, conformation, fluorescence property, electric potential as well as wettability can be monitored via transmembrane ionic current, fluorescence intensity, faraday current signals of nanochannels and so on. Herein, the modification methodologies of nanochannels and targets-detecting application are summarized in ions, small molecules, as well as biomolecules, and systematically reviewed are the nanochannel-based detection means including 1) by transmembrane current signals; 2) by the coordination of current- and fluorescence-dual signals; 3) by faraday current signals from nanochannel-based electrode. Read More

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Parameterizing elastic network models to capture the dynamics of proteins.

J Comput Chem 2021 Jun 11. Epub 2021 Jun 11.

Unité de Dynamique Structurale des Macromolécules, Institut Pasteur, UMR 3528 du CNRS, Paris, France.

Coarse-grained normal mode analyses of protein dynamics rely on the idea that the geometry of a protein structure contains enough information for computing its fluctuations around its equilibrium conformation. This geometry is captured in the form of an elastic network (EN), namely a network of edges between its residues. The normal modes of a protein are then identified with the normal modes of its EN. Read More

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Perturbation of ribosomal subunits dynamics by inhibitors of tRNA translocation.

RNA 2021 Jun 11. Epub 2021 Jun 11.

Max Planck Institute for Biophysical Chemistry

Many antibiotics that bind to the ribosome inhibit translation by blocking the movement of tRNAs and mRNA or interfering with ribosome dynamics, which impairs the formation of essential translocation intermediates. Here we show how translocation inhibitors viomycin (Vio), neomycin (Neo), paromomycin (Par), kanamycin (Kan), spectinomycin (Spc), hygromycin B (HygB), and streptomycin (Str, an antibiotic that does not inhibit tRNA movement), affect principal motions of the small ribosomal subunits (SSU) during EF-G-promoted translocation. Using ensemble kinetics, we studied the SSU body domain rotation and SSU head domain swiveling in real time. Read More

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Complement Receptor 3 Forms a Compact High-Affinity Complex with iC3b.

J Immunol 2021 Jun 11. Epub 2021 Jun 11.

Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark;

Complement receptor 3 (CR3, also known as Mac-1, integrin αβ, or CD11b/CD18) is expressed on a subset of myeloid and certain activated lymphoid cells. CR3 is essential for the phagocytosis of complement-opsonized particles such as pathogens and apoptotic or necrotic cells opsonized with the complement fragment iC3b and, to a lesser extent, C3dg. Although the interaction between the iC3b thioester domain and the ligand binding CR3 α I-domain is structurally and functionally well characterized, the nature of additional CR3-iC3b interactions required for phagocytosis of complement-opsonized objects remains obscure. Read More

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Effect of pH on pulsed light inactivation of polyphenol oxidase.

Enzyme Microb Technol 2021 Aug 3;148:109812. Epub 2021 May 3.

Cátedra Alimentos para la Salud, Universidad Católica de Murcia (UCAM), Campus de los Jerónimos 135, Guadalupe, 30107, Murcia, Spain. Electronic address:

The inactivation of diverse food enzymes by pulsed light (PL) has been described before, including the inactivation of polyphenol oxidase (PPO) (at pH 6.5). Since the pH affects the conformation of enzymes, it may influence the inactivation of enzymes by PL. Read More

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Archaeal SRP RNA and SRP19 facilitate the assembly of SRP54-FtsY targeting complex.

Biochem Biophys Res Commun 2021 Jun 8;566:53-58. Epub 2021 Jun 8.

Department of Biochemistry, Bose Institute, Kolkata, India. Electronic address:

The signal recognition particle (SRP) plays an essential role in protein translocation across biological membranes. Stable complexation of two GTPases in the signal recognition particle (SRP) and its receptor (SR) control the delivery of nascent polypeptide to the membrane translocon. In archaea, protein targeting is mediated by the SRP54/SRP19/7S RNA ribonucleoprotein complex (SRP) and the FtsY protein (SR). Read More

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Low cytotoxic quinoline-4-carboxylic acids derived from vanillin precursors as potential human dihydroorotate dehydrogenase inhibitors.

Bioorg Med Chem Lett 2021 Jun 8;46:128194. Epub 2021 Jun 8.

Faculty of Science, Department of Chemistry, University of Kragujevac, R. Domanovica 12, 34000 Kragujevac, Serbia. Electronic address:

Twenty novel 2-substituted quinoline-4-carboxylic acids bearing amide moiety were designed and synthesized by Doebner reaction. Human dihydroorotate dehydrogenase (hDHODH) was recognized as a biological target and all compounds were screened as potential hDHODH inhibitors in an enzyme inhibition assay. The prepared heterocycles were also evaluated for their cytotoxic effects on the healthy HaCaT cell line while lipophilic properties were considered on the basis of experimentally determined logD values at physiological pH. Read More

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Aspartic protease-pepstatin A interactions: Structural insights on the thermal inactivation mechanism.

Biochimie 2021 Jun 8. Epub 2021 Jun 8.

Kaypeeyes Biotech Private Limited, R&D Center, Hebbal Industrial Area, Mysuru, 570016, Karnataka, India. Electronic address:

Aspartic proteases are the targets for structure-based drug design for their role in physiological processes and pharmaceutical applications. Structural insights into the thermal inactivation mechanism of an aspartic protease in presence and absence of bound pepstatin A have been obtained by kinetics of thermal inactivation, CD, fluorescence spectroscopy and molecular dynamic simulations. The irreversible thermal inactivation of the aspartic protease comprised of loss of tertiary and secondary structures succeeded by the loss of activity, autolysis and aggregation The enthalpy and entropy of thermal inactivation of the enzyme in presence of pepstatin A increased from 81. Read More

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Synthesis, molecular docking, dynamic simulation and pharmacological characterization of potent multifunctional agent (dual GPR40-PPARγ agonist) for the treatment of experimental type 2 diabetes.

Eur J Pharmacol 2021 Jun 8:174244. Epub 2021 Jun 8.

Facultad de Farmacia, Universidad Autónoma Del Estado de Morelos, Cuernavaca, Morelos, 62209, México.

The current manuscript describes two molecules that were designed against PPARγ and GPR40 receptors. The preparation of the compounds was carried out following a synthetic route of multiple steps. Then, the mRNA expression levels of PPARγ, GLUT4, and GPR40 induced by compounds were measured and quantified in adipocyte and β-pancreatic cell cultures. Read More

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MagC is a NplC/P60-like member of the α-2-macroglobulin Mag complex of Pseudomonas aeruginosa that interacts with peptidoglycan.

FEBS Lett 2021 Jun 11. Epub 2021 Jun 11.

Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000, Grenoble, France.

Bacterial alpha-2-macroglobulins (A2Ms) structurally resemble the large spectrum protease inhibitors of the eukaryotic immune system. In Pseudomonas aeruginosa, MagD acts as an A2M and is expressed within a six-gene operon encoding the MagA-F proteins. In this work, we employ isothermal calorimetry (ITC), analytical ultracentrifugation (AUC), and X-ray crystallography to investigate the function of MagC and show that MagC associates with the macroglobulin complex and with the peptidoglycan (PG). Read More

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Electric-Field-Induced Chirality in Columnar Liquid Crystals.

J Am Chem Soc 2021 Jun 11. Epub 2021 Jun 11.

Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.

We describe a novel class of tetraphenylbenzene-based discotic molecules with exceptional self-assembling properties. Absorption and fluorescence studies confirmed the formation of -type aggregates in solution. The discotic mesogens also show an enhancement of the emission upon aggregation. Read More

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Hydrogen-Bonded Organic Framework Microlasers with Conformation-Induced Color-Tunable Output.

ACS Appl Mater Interfaces 2021 Jun 11. Epub 2021 Jun 11.

Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

Porous organic frameworks have emerged as the promising platforms to construct tunable microlasers. Most of these microlasers are achieved from metal-organic frameworks via meticulously accommodating the laser dyes with the sacrifice of the pore space, yet they often suffer from the obstacles of either relatively limited gain concentration or sophisticated fabrication techniques. Herein, we reported on the first hydrogen-bonded organic framework (HOF) microlasers with color-tunable performance based on conformation-dependent stimulated emissions. Read More

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Induced VCD and conformational chirality in host-guest complexes of a chiral ammonium salt with crown ethers.

Phys Chem Chem Phys 2021 Jun 11. Epub 2021 Jun 11.

Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150, 44801 Bochum, Germany.

The hydrogen bonded complexes of the chiral ammonium salt α-methylbenzyl ammonium chloride (MBA-H+Cl-) and the achiral crown ethers 18c6 and 15c5 serve as model systems to investigate the effect of host-guest complex formation on the conformational preferences of the macrocycles. We demonstrate that the intermolecular interactions result in new VCD signatures, that can be assigned to vibrational modes of the crown ethers. Based on a detailed conformational analysis, we investigate the origin of these signatures and discuss induced VCD (iVCD) and conformational chirality as possible sources of VCD intensity. Read More

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Longer charged amino acids favor β-strand formation in hairpin peptides.

J Pept Sci 2021 Jun 10:e3333. Epub 2021 Jun 10.

Department of Chemistry, National Taiwan University, Taipei, Taiwan.

Interactions between charged amino acids significantly influence the structure and function of proteins. The encoded charged amino acids Asp, Glu, Arg, and Lys have different number of hydrophobic methylenes linking the backbone to the charged functionality. It remains to be fully understood how does this difference in the number of methylenes affect protein structure stability. Read More

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High-resolution analysis of chromosome conformation in hyperthermophilic archaea.

STAR Protoc 2021 Jun 28;2(2):100562. Epub 2021 May 28.

Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN 47405, USA.

Chromosome conformation capture (3C) techniques are emerging as promising approaches to study genome organization in Archaea, the least understood domain of life in terms of chromosome biology. Here, we describe a 3C technique combined with deep sequencing for the hyperthermophilic archaeal genus . Instead of using restriction enzymes compatible with fill-in labeling, this protocol uses the 4-bp blunt cutter AluI to generate high-resolution (up to 2 kb) contact maps from species. Read More

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Impact of Diet Supplementation and Age at Slaughter on Carcass Characteristics of Creole Goats.

Front Vet Sci 2021 25;8:671948. Epub 2021 May 25.

INRAE Unité de Recherches Zootechniques, Centre INRAE Antilles-Guyane, Paris, France.

The objective of this study was to evaluate the effects of diet and age on finishing performances and carcass characteristics of male Creole goats. A total of 91 weaned male Creole kids [84 days old ± 7 days, 9.2 kg live weight (LW) ± 0. Read More

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Advantages of Organic Halogen Bonding for Halide Recognition.

Supramol Chem 2016 11;28(7-8):665-672. Epub 2015 Dec 11.

Department of Chemistry and Biochemistry, University of Montana, Missoula MT, USA.

The study of hydrogen bonding organocatalysis is rapidly expanding. Much research has been directed at making catalysts more active and selective, with less attention on fundamental design strategies. This study systematically increases steric hindrance at the active site of pH switchable urea organocatalysts. Read More

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December 2015

ATP biphasically modulates LLPS of TDP-43 PLD by specifically binding arginine residues.

Commun Biol 2021 Jun 10;4(1):714. Epub 2021 Jun 10.

Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.

Mysteriously neurons maintain ATP concentrations of ~3 mM but whether ATP modulates TDP-43 LLPS remains completely unexplored. Here we characterized the effect of ATP on LLPS of TDP-43 PLD and seven mutants by DIC and NMR. The results revealed: 1) ATP induces and subsequently dissolves LLPS of TDP-43 PLD by specifically binding Arg saturated at 1:100. Read More

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Structural and functional insights into the mechanism of action of plant borate transporters.

Sci Rep 2021 Jun 10;11(1):12328. Epub 2021 Jun 10.

Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.

Boron has essential roles in plant growth and development. BOR proteins are key in the active uptake and distribution of boron, and regulation of intracellular boron concentrations. However, their mechanism of action remains poorly studied. Read More

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Characterization of metapopulation of Ellobium chinense through Pleistocene expansions and four covariate COI guanine-hotspots linked to G-quadruplex conformation.

Sci Rep 2021 Jun 10;11(1):12239. Epub 2021 Jun 10.

Department of Biology Education, Teachers College and Institute for Phylogenomics and Evolution, Kyungpook National University, Daegu, 41566, South Korea.

The land snail Ellobium chinense (L. Pfeiffer, 1855) (Eupulmonata, Ellobiida, Ellobiidae), which inhabits the salt marshes along the coastal areas of northwestern Pacific, is an endangered species on the IUCN Red List. Over recent decades, the population size of E. Read More

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Target identification for small-molecule discovery in the FOXO3a tumor-suppressor pathway using a biodiverse peptide library.

Cell Chem Biol 2021 Jun 1. Epub 2021 Jun 1.

Medical Research Council Cancer Unit, University of Cambridge, Hills Road, Cambridge CB2 0XZ, UK; Center for Chemical Biology & Therapeutics, inStem & NCBS, Bellary Road, Bangalore 560065, India; PhoreMost Ltd., Babraham Research Campus, Cambridge CB22 3AT, UK. Electronic address:

Genetic screening technologies to identify and validate macromolecular interactions (MMIs) essential for complex pathways remain an important unmet need for systems biology and therapeutics development. Here, we use a library of peptides from diverse prokaryal genomes to screen MMIs promoting the nuclear relocalization of Forkhead Box O3 (FOXO3a), a tumor suppressor more frequently inactivated by post-translational modification than mutation. A hit peptide engages the 14-3-3 family of signal regulators through a phosphorylation-dependent interaction, modulates FOXO3a-mediated transcription, and suppresses cancer cell growth. Read More

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Hierarchical Two-Level Supramolecular Chirality of an Achiral Anthracene-Based Tetracationic Nanotube in Water.

Angew Chem Int Ed Engl 2021 Jun 9. Epub 2021 Jun 9.

College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China.

Herein, we report an achiral anthracene-based tetracationic nanotube (1⋅4Cl ) that shows two levels of supramolecular chirality: namely, conformationally adaptive host-guest complexation with nucleoside triphosphates (e.g. ATP, GTP, CTP, and UTP) and twisted packing of the chiral host-guest complexes in water. Read More

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New substrates and determinants for tRNA recognition of RNA methyltransferase DNMT2/TRDMT1.

RNA Biol 2021 Jun 10:1-15. Epub 2021 Jun 10.

College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China.

Methylation is a common post-transcriptional modification of tRNAs, particularly in the anticodon loop region. The cytosine 38 (C38) in tRNAs, such as tRNA, tRNA, tRNA, and tRNA, can be methylated by human DNMT2/TRDMT1 and some homologs found in bacteria, plants, and animals. However, the substrate properties and recognition mechanism of DNMT2/TRDMT1 remain to be explored. Read More

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Cell Adhesion Characteristics on Tantalum Pentoxide Gate Insulator for Cultured-Cell-Gate Field-Effect Transistor.

Langmuir 2021 Jun 10. Epub 2021 Jun 10.

Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.

Understanding the interaction between living cells and a tantalum pentoxide (TaO) gate electrode is important for controlling cell adhesion and functions when developing a cultured-cell-gate field-effect transistor biosensor. In this study, we evaluate the cell adhesion characteristics of the TaO membrane without or with a polydopamine (pDA) coating for chondrocytes, which is expected as a treatment for improving biocompatibility. As a result, the native and pDA-modified TaO membranes are shown to have the appropriate surface tension (35-40 dyn/cm) for the adhesion of chondrocytes owing to the contribution of surface tension to not only the nonspecific adsorption of serum proteins as the scaffold of chondrocytes but also the maintenance of the conformation of serum proteins. Read More

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