keyword
MENU ▼
Read by QxMD icon Read
search

Macromolecule

keyword
https://www.readbyqxmd.com/read/28211226/supramolecularly-engineered-amphiphilic-macromolecules-molecular-interaction-overrules-packing-parameters
#1
Prithankar Pramanik, Debes Ray, Vinod K Aswal, Suhrit Ghosh
We report molecular interaction-driven self-assembly of supramolecularly engineered amphiphilic macromolecules (SEAM) containing a single supramolecular structure-directing unit (SSDU) consisting of an H-bonding group connected to a naphthalene diimide chromophore. Two such SEAMs, P1-50 and P2-50, having the identical chemical structure and hydrophobic/hydrophilic balance, exhibit distinct self-assembled structures (polymersome and cylindrical micelle, respectively) due to a difference in the H-bonding group (hydrazide or amide, respectively) of the single SSDU...
February 17, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28210205/the-atp-gated-p2x7-receptor-as-a-target-for-the-treatment-of-drug-resistant-epilepsy
#2
REVIEW
Edward Beamer, Wolfgang Fischer, Tobias Engel
Despite the progress made in the development of new antiepileptic drugs (AEDs), the biggest challenges that epilepsy presents to drug development have remained unchanged for the last 80 years: finding a treatment with potential for modifying disease progression and reducing the percentage of patients resistant to all pharmacological interventions. The mechanism of action of the majority of AEDs is based on blocking Na(+) and/or Ca(2+) channels, promotion of GABA or inhibition of glutamate signaling. In order for further progress to be made, however, a fuller picture of epilepsy will need to be considered, including changes to blood-brain barrier permeability, synaptic plasticity, network reorganization, and gliosis...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28209717/autophagy-metabolism-and-cancer
#3
Jessie Yanxiang Guo, Eileen White
Macroautophagy (autophagy hereafter) is a process that collects cytoplasmic components, particularly mitochondria, and degrades them in lysosomes. In mammalian systems, basal autophagy levels are normally low but are profoundly stimulated by starvation and essential for survival. Cancer cells up-regulate autophagy and can be more autophagy-dependent than most normal tissues. Genetic deficiency in essential autophagy genes in tumors in many autochthonous mouse models for cancer reduces tumor growth. In K-ras(G12D)-driven non-small cell lung cancer (NSCLC) and other models, autophagy sustains metabolism and survival...
February 16, 2017: Cold Spring Harbor Symposia on Quantitative Biology
https://www.readbyqxmd.com/read/28208731/in-vivo-imaging-of-local-gene-expression-induced-by-magnetic-hyperthermia
#4
Olivier Sandre, Coralie Genevois, Eneko Garaio, Laurent Adumeau, Stéphane Mornet, Franck Couillaud
The present work aims to demonstrate that colloidal dispersions of magnetic iron oxide nanoparticles stabilized with dextran macromolecules placed in an alternating magnetic field can not only produce heat, but also that these particles could be used in vivo for local and noninvasive deposition of a thermal dose sufficient to trigger thermo-induced gene expression. Iron oxide nanoparticles were first characterized in vitro on a bio-inspired setup, and then they were assayed in vivo using a transgenic mouse strain expressing the luciferase reporter gene under transcriptional control of a thermosensitive promoter...
February 8, 2017: Genes
https://www.readbyqxmd.com/read/28208699/induction-of-syndecan-4-by-organic-inorganic-hybrid-molecules-with-a-1-10-phenanthroline-structure-in-cultured-vascular-endothelial-cells
#5
Takato Hara, Takayuki Kojima, Hiroka Matsuzaki, Takehiro Nakamura, Eiko Yoshida, Yasuyuki Fujiwara, Chika Yamamoto, Shinichi Saito, Toshiyuki Kaji
Organic-inorganic hybrid molecules constitute analytical tools used in biological systems. Vascular endothelial cells synthesize and secrete proteoglycans, which are macromolecules consisting of a core protein and glycosaminoglycan side chains. Although the expression of endothelial proteoglycans is regulated by several cytokines/growth factors, there may be alternative pathways for proteoglycan synthesis aside from downstream pathways activated by these cytokines/growth factors. Here, we investigated organic-inorganic hybrid molecules to determine a variant capable of analyzing the expression of syndecan-4, a transmembrane heparan-sulfate proteoglycan, and identified 1,10-phenanthroline (o-Phen) with or without zinc (Zn-Phen) or rhodium (Rh-Phen)...
February 8, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28208462/beyond-flory-theory-distribution-functions-for-interacting-lattice-trees
#6
Angelo Rosa, Ralf Everaers
While Flory theories [J. Isaacson and T. C. Lubensky, J. Physique Lett. 41, 469 (1980)JPSLBO0302-072X10.1051/jphyslet:019800041019046900; M. Daoud and J. F. Joanny, J. Physique 42, 1359 (1981)JOPQAG0302-073810.1051/jphys:0198100420100135900; A. M. Gutin et al., Macromolecules 26, 1293 (1993)MAMOBX0024-929710.1021/ma00058a016] provide an extremely useful framework for understanding the behavior of interacting, randomly branching polymers, the approach is inherently limited. Here we use a combination of scaling arguments and computer simulations to go beyond a Gaussian description...
January 2017: Physical Review. E
https://www.readbyqxmd.com/read/28207780/analyzing-pepsin-degradation-assay-conditions-used-for-allergenicity-assessments-to-ensure-that-pepsin-susceptible-and-pepsin-resistant-dietary-proteins-are-distinguishable
#7
Rong Wang, Thomas C Edrington, S Bradley Storrs, Kathleen S Crowley, Jason M Ward, Thomas C Lee, Zi L Liu, Bin Li, Kevin C Glenn
The susceptibility of a dietary protein to proteolytic degradation by digestive enzymes, such as gastric pepsin, provides information on the likelihood of systemic exposure to a structurally intact and biologically active macromolecule, thus informing on the safety of proteins for human and animal consumption. Therefore, the purpose of standardized in vitro degradation studies that are performed during protein safety assessments is to distinguish whether proteins of interest are susceptible or resistant to pepsin degradation via a study design that enables study-to-study comparison...
2017: PloS One
https://www.readbyqxmd.com/read/28203648/gene-regulatory-effects-of-disease-associated-variation-in-the-nrf2-network
#8
Sarah E Lacher, Matthew Slattery
Reactive oxygen species (ROS), which are both a natural byproduct of oxidative metabolism and an undesirable byproduct of many environmental stressors, can damage all classes of cellular macromolecules and promote diseases from cancer to neurodegeneration. The actions of ROS are mitigated by the transcription factor NRF2, which regulates expression of antioxidant genes via its interaction with cis-regulatory antioxidant response elements (AREs). However, despite the seemingly straightforward relationship between the opposing forces of ROS and NRF2, regulatory precision in the NRF2 network is essential...
December 2016: Curr Opin Toxicol
https://www.readbyqxmd.com/read/28203306/accounting-for-thermodynamic-non-ideality-in-the-guinier-region-of-small-angle-scattering-data-of-proteins
#9
David J Scott
Hydrodynamic studies of the solution properties of proteins and other biological macromolecules are often hard to interpret when the sample is present at a reasonably concentrated solution. The reason for this is that solutions exhibit deviations from ideal behaviour which is manifested as thermodynamic non-ideality. The range of concentrations at which this behaviour typically is exhibited is as low as 1-2 mg/ml, well within the range of concentrations used for their analysis by techniques such as small-angle scattering...
December 2016: Biophysical Reviews
https://www.readbyqxmd.com/read/28202838/role-of-ad4-binding-protein-steroidogenic-factor-1-in-regulating-nadph-production-in-adrenocortical-y-1-cells
#10
Bing Li, Takashi Baba, Kanako Miyabayashi, Tetsuya Sato, Yuichi Shima, Tomomi Ichinose, Daisuke Miura, Yasuyuki Ohkawa, Mikita Suyama, Ken-Ichirou Morohashi
Ad4-binding protein/steroidogenic factor 1 (Ad4BP/SF-1), a member of the nuclear receptor superfamily, is expressed in steroidogenic cells and regulates all steroidogenic gene expression. We recently employed mRNA and chromatin immunoprecipitation sequence (ChIP-seq) to demonstrate that Ad4BP/SF-1 directly regulates the expression of nearly all glycolytic genes. The pentose phosphate pathway (PPP) contributes to the production of nicotinamide adenine dinucleotide phosphate (NADPH). Although the expression of PPP genes and intracellular NADPH were decreased by Ad4BP/SF-1 knockdown, these genes were not the direct targets of Ad4BP/SF-1...
February 14, 2017: Endocrine Journal
https://www.readbyqxmd.com/read/28196890/dync1h1-mutations-associated-with-neurological-diseases-compromise-processivity-of-dynein-dynactin-cargo-adaptor-complexes
#11
Ha Thi Hoang, Max A Schlager, Andrew P Carter, Simon L Bullock
Mutations in the human DYNC1H1 gene are associated with neurological diseases. DYNC1H1 encodes the heavy chain of cytoplasmic dynein-1, a 1.4-MDa motor complex that traffics organelles, vesicles, and macromolecules toward microtubule minus ends. The effects of the DYNC1H1 mutations on dynein motility, and consequently their links to neuropathology, are not understood. Here, we address this issue using a recombinant expression system for human dynein coupled to single-molecule resolution in vitro motility assays...
February 14, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28195674/solvent-and-halogen-free-modification-of-biobased-polyphenols-to-introduce-vinyl-groups-versatile-aromatic-building-blocks-for-polymer-synthesis
#12
Antoine Duval, Luc Averous
Various biobased polyphenols (lignins and condensed tannins) were derivatized with vinyl ethylene carbonate, a functional cyclic carbonate, to obtain multifunctional aromatic polymers carrying vinyl groups. The reaction was optimized on a condensed tannin and soda lignin. In both cases, a full conversion of the phenol groups is achieved in only 1 h at 150 °C, without solvent and with K2CO3 as cheap and safe catalyst. This reaction was later applied to other condensed tannins and technical lignins (Kraft and organosolv), showing only little dependence on the chemical structure of the polyphenols...
February 14, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28193769/long-noncoding-rnas-at-the-intersection-of-cancer-and-chromatin-biology
#13
Adam M Schmitt, Howard Y Chang
Although only 2% of the genome encodes protein, RNA is transcribed from the majority of the genetic sequence, suggesting a massive degree of cellular functionality is programmed in the noncoding genome. The mammalian genome contains tens of thousands of long noncoding RNAs (lncRNAs), many of which occur at disease-associated loci or are specifically expressed in cancer. Although the vast majority of lncRNAs have no known function, recurring molecular mechanisms for lncRNAs are now being observed in chromatin regulation and cancer pathways and emerging technologies are now providing tools to interrogate lncRNA molecular interactions and determine function of these abundant cellular macromolecules...
February 13, 2017: Cold Spring Harbor Perspectives in Medicine
https://www.readbyqxmd.com/read/28193045/contribution-of-ribonucleic-acid-rna-to-the-fourier-transform-infrared-ftir-spectrum-of-eukaryotic-cells
#14
Paolo Zucchiatti, Elisa Mitri, Saša Kenig, Fulvio Billè, George Kourousias, Diana Eva Bedolla, Lisa Vaccari
We report on an optimized protocol for the digestion of cellular RNA, which minimally affects the cell membrane integrity, maintaining substantially unaltered the vibrational contributions of the other cellular macromolecules. The design of this protocol allowed us to collect the first Fourier transform infrared (FTIR) spectra of intact hydrated B16 mouse melanoma cells deprived of RNA and to highlight the in-cell diagnostic spectral features of it. Complementing the cellular results with the FTIR analysis of extracted RNA, ds-DNA, ss-cDNA and isolated nuclei, we verified that the spectral component centered at ∼1220 cm(-1) is a good qualitative and semiquantitative marker of cellular DNA, since it is minimally affected by cellular RNA removal...
December 20, 2016: Analytical Chemistry
https://www.readbyqxmd.com/read/28192420/atomic-resolution-structures-from-fragmented-protein-crystals-with-the-cryoem-method-microed
#15
M Jason de la Cruz, Johan Hattne, Dan Shi, Paul Seidler, Jose Rodriguez, Francis E Reyes, Michael R Sawaya, Duilio Cascio, Simon C Weiss, Sun Kyung Kim, Cynthia S Hinck, Andrew P Hinck, Guillermo Calero, David Eisenberg, Tamir Gonen
Traditionally, crystallographic analysis of macromolecules has depended on large, well-ordered crystals, which often require significant effort to obtain. Even sizable crystals sometimes suffer from pathologies that render them inappropriate for high-resolution structure determination. Here we show that fragmentation of large, imperfect crystals into microcrystals or nanocrystals can provide a simple path for high-resolution structure determination by the cryoEM method MicroED and potentially by serial femtosecond crystallography...
February 13, 2017: Nature Methods
https://www.readbyqxmd.com/read/28192292/single-molecule-optical-measurements-of-orientation-and-rotations-of-biological-macromolecules
#16
Deborah Y Shroder, Lisa G Lippert, Yale E Goldman
Subdomains of macromolecules often undergo large orientation changes during their catalytic cycles that are essential for their activity. Tracking these rearrangements in real time opens a powerful window into the link between protein structure and functional output. Site-specific labeling of individual molecules with polarized optical probes and measurement of their spatial orientation can give insight into the crucial conformational changes, dynamics, and fluctuations of macromolecules. Here we describe the range of single molecule optical technologies that can extract orientation information from these probes, review the relevant types of probes and labeling techniques, and highlight the advantages and disadvantages of these technologies for addressing specific inquiries...
November 22, 2016: Methods and Applications in Fluorescence
https://www.readbyqxmd.com/read/28192200/the-binding-capacity-of-%C3%AE-1%C3%AE-1-%C3%AE-2%C3%AE-1-and-%C3%AE-10%C3%AE-1-integrins-depends-on-non-collagenous-surface-macromolecules-rather-than-the-collagens-in-cartilage-fibrils
#17
Christian Woltersdorf, Melanie Bonk, Birgit Leitinger, Mikko Huhtala, Jarmo Käpylä, Jyrki Heino, Christian Gil Girol, Stephan Niland, Johannes A Eble, Peter Bruckner, Rita Dreier, Uwe Hansen
Interactions of cells with supramolecular aggregates of the extracellular matrix (ECM) are mediated, in part, by cell surface receptors of the integrin family. These are important molecular components of cell surface-suprastructures regulating cellular activities in general. A subfamily of β1-integrins with von Willebrand-factorA-like domains (I-domains) in their α-chains can bind to collagen molecules and, therefore, are considered as important cellular mechano-receptors. Here we show that chondrocytes strongly bind to cartilage collagens in the form of individual triple helical molecules but very weakly to fibrils formed by the same molecules...
February 10, 2017: Matrix Biology: Journal of the International Society for Matrix Biology
https://www.readbyqxmd.com/read/28191714/solid-state-nmr-and-epr-spectroscopy-of-mn-2-substituted-atp-fueled-protein-engines
#18
Thomas Wiegand, Denis Lacabanne, Katharina Keller, Riccardo Cadalbert, Lauriane Lecoq, Maxim Yulikov, Laurent Terradot, Gunnar Jeschke, Beat H Meier, Anja Böckmann
Paramagnetic metal ions deliver structural information both in EPR and solid-state NMR experiments, offering a profitable synergetic approach to study bio-macromolecules. We demonstrate the spectral consequences of Mg(2+) / Mn(2+) substitution and the resulting information contents for two different ATP:Mg(2+) -fueled protein engines, a DnaB helicase from Helicobacter pylori active in the bacterial replisome, and the ABC transporter BmrA, a bacterial efflux pump. We show that, while EPR spectra report on metal binding and provide information on the geometry of the metal centers in the proteins, paramagnetic relaxation enhancements identified in the NMR spectra can be used to localize residues at the binding site...
February 13, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28191458/structural-study-of-heterogeneous-biological-samples-by-cryoelectron-microscopy-and-image-processing
#19
REVIEW
H E White, A Ignatiou, D K Clare, E V Orlova
In living organisms, biological macromolecules are intrinsically flexible and naturally exist in multiple conformations. Modern electron microscopy, especially at liquid nitrogen temperatures (cryo-EM), is able to visualise biocomplexes in nearly native conditions and in multiple conformational states. The advances made during the last decade in electronic technology and software development have led to the revelation of structural variations in complexes and also improved the resolution of EM structures. Nowadays, structural studies based on single particle analysis (SPA) suggests several approaches for the separation of different conformational states and therefore disclosure of the mechanisms for functioning of complexes...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28190782/onedep-unified-wwpdb-system-for-deposition-biocuration-and-validation-of-macromolecular-structures-in-the-pdb-archive
#20
Jasmine Y Young, John D Westbrook, Zukang Feng, Raul Sala, Ezra Peisach, Thomas J Oldfield, Sanchayita Sen, Aleksandras Gutmanas, David R Armstrong, John M Berrisford, Li Chen, Minyu Chen, Luigi Di Costanzo, Dimitris Dimitropoulos, Guanghua Gao, Sutapa Ghosh, Swanand Gore, Vladimir Guranovic, Pieter M S Hendrickx, Brian P Hudson, Reiko Igarashi, Yasuyo Ikegawa, Naohiro Kobayashi, Catherine L Lawson, Yuhe Liang, Steve Mading, Lora Mak, M Saqib Mir, Abhik Mukhopadhyay, Ardan Patwardhan, Irina Persikova, Luana Rinaldi, Eduardo Sanz-Garcia, Monica R Sekharan, Chenghua Shao, G Jawahar Swaminathan, Lihua Tan, Eldon L Ulrich, Glen van Ginkel, Reiko Yamashita, Huanwang Yang, Marina A Zhuravleva, Martha Quesada, Gerard J Kleywegt, Helen M Berman, John L Markley, Haruki Nakamura, Sameer Velankar, Stephen K Burley
OneDep, a unified system for deposition, biocuration, and validation of experimentally determined structures of biological macromolecules to the PDB archive, has been developed as a global collaboration by the worldwide PDB (wwPDB) partners. This new system was designed to ensure that the wwPDB could meet the evolving archiving requirements of the scientific community over the coming decades. OneDep unifies deposition, biocuration, and validation pipelines across all wwPDB, EMDB, and BMRB deposition sites with improved focus on data quality and completeness in these archives, while supporting growth in the number of depositions and increases in their average size and complexity...
February 3, 2017: Structure
keyword
keyword
115812
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"