keyword
MENU ▼
Read by QxMD icon Read
search

Biophysics

keyword
https://www.readbyqxmd.com/read/28106980/structural-snapshots-of-an-engineered-cystathionine-%C3%AE-lyase-reveal-the-critical-role-of-electrostatic-interactions-in-the-active-site
#1
Wupeng Yan, Everett M Stone, Yan Jessie Zhang
Enzyme therapeutics that can degrade L-methionine (L-Met) are of great interest as numerous malignancies are exquisitely sensitive to L-Met depletion. To exhaust the pool of the methionine in human serum, we previously engineered an L-Met degrading enzyme based on the human cystathionine-γ-lyase scaffold (hCGL-NLV) in order to circumvent immunogenicity and stability issues observed in the preclinical application of bacterial derived methionine-γ-lyases (MGL). To gain further insights into structure/activity relationships governing the chemistry of the hCGL-NLV lead molecule, we undertook a biophysical characterization campaign that captured crystal structures (2...
January 20, 2017: Biochemistry
https://www.readbyqxmd.com/read/28106668/primidone-inhibits-trpm3-and-attenuates-thermal-nociception-in-vivo
#2
Ute Krügel, Isabelle Straub, Holger Beckmann, Michael Schaefer
The melastatin-related transient receptor potential channel TRPM3 is a nonselective cation channel expressed in nociceptive neurons and activated by heat. Since TRPM3-deficient mice show inflammatory thermal hyperalgesia, pharmacological inhibition of TRPM3 may exert antinociceptive properties. Fluorometric Ca influx assays and a compound library containing approved or clinically tested drugs were used to identify TRPM3 inhibitors. Biophysical properties of channel inhibition were assessed using electrophysiological methods...
January 12, 2017: Pain
https://www.readbyqxmd.com/read/28106378/cell-selective-apoptosis-induced-by-polymorphic-alteration-of-self-assembled-silica-nano-webs
#3
Meysam Keshavarz, Bo Tan, Krishnan Venkatakrishnan
The biocompatibility of silicon-based nanomaterial makes it suitable for biophysical and biomedical applications. However, the application of silicon-based nanomaterials has been mainly restricted to nanoparticles (NPs) as a potential drug carrier and the extracellular matrix (ECM) as a platform for cell adhesion and proliferation. Here, we introduced silica NPs self-assembled into a 3D nano-web architecture that was shown to inherit the therapeutic and proliferative attributes of both NPs and ECMs. The self-assembled silica nano-web (SNW) has, therefore, not only shown targeted drug-like behavior in HeLa cells without the use of bio-markers but also has shown ECM characteristics...
January 20, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28105525/characterization-of-the-cell-polarity-gene-crumbs-during-the-early-development-and-maintenance-of-the-squid-vibrio-light-organ-symbiosis
#4
Suzanne M Peyer, Elizabeth A C Heath-Heckman, Margaret J McFall-Ngai
The protein Crumbs is a determinant of apical-basal cell polarity and plays a role in apoptosis of epithelial cells and their protection against photodamage. Using the squid-vibrio system, a model for development of symbiotic partnerships, we examined the modulation of the crumbs gene in host epithelial tissues during initiation and maintenance of the association. The extracellular luminous symbiont Vibrio fischeri colonizes the apical surfaces of polarized epithelia in deep crypts of the Euprymna scolopes light organ...
January 20, 2017: Development Genes and Evolution
https://www.readbyqxmd.com/read/28104532/sphingolipids-and-glycerophospholipids-the-ying-and-yang-of-lipotoxicity-in-metabolic-diseases
#5
REVIEW
S Rodriguez-Cuenca, V Pellegrinelli, M Campbell, M Oresic, A Vidal-Puig
Sphingolipids in general and ceramides in particular, contribute to pathophysiological mechanisms by modifying signalling and metabolic pathways. Here, we present the available evidence for a bidirectional homeostatic crosstalk between sphingolipids and glycerophospholipids, whose dysregulation contributes to lipotoxicity induced metabolic stress. The initial evidence for this crosstalk originates from simulated models designed to investigate the biophysical properties of sphingolipids in plasma membrane representations...
January 16, 2017: Progress in Lipid Research
https://www.readbyqxmd.com/read/28104368/interaction-of-capsaicin-with-calf-thymus-dna-a-multi-spectroscopic-and-molecular-modelling-study
#6
Faizan Abul Qais, K M Abdullah, Md Maroof Alam, Imrana Naseem, Iqbal Ahmad
Studying the mode of interaction between small molecules and DNA have received much attention in recent years, as many drugs have been reported to directly interact with DNA thereby regulating the expression of many genes. Capsaicin is a capsaiciniods family phytocompound having many therapeutic applications including diabetic neuropathy, rheumatoid arthritis, prevention of DNA strand breaks and chromosomal aberrations. In this study, we have investigated the interaction of capsaicin with calf thymus DNA using a number of biophysical techniques to get an insight and better understanding of the interaction mechanism...
January 16, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28102755/anionic-lipids-and-the-maintenance-of-membrane-electrostatics-in-eukaryotes
#7
Matthieu Pierre Platre, Yvon Jaillais
A wide range of signaling processes occurs at the cell surface through the reversible association of proteins from the cytosol to the plasma membrane. Some low abundant lipids are enriched at the membrane of specific compartments and thereby contribute to the identity of cell organelles by acting as biochemical landmarks. Lipids also influence membrane biophysical properties, which emerge as an important feature in specifying cellular territories. Such parameters are crucial for signal transduction and include lipid packing, membrane curvature and electrostatics...
January 19, 2017: Plant Signaling & Behavior
https://www.readbyqxmd.com/read/28102402/brillouin-flow-cytometry-for-label-free-mechanical-phenotyping-of-the-nucleus
#8
Jitao Zhang, Xuefei A Nou, Hanyoup Kim, Giuliano Scarcelli
The mechanical properties of the nucleus are closely related to many cellular functions; thus, measuring nuclear mechanical properties is crucial to our understanding of cell biomechanics and could lead to intrinsic biophysical contrast mechanisms to classify cells. Although many technologies have been developed to characterize cell stiffness, they generally require contact with the cell and thus cannot provide direct information on nuclear mechanical properties. In this work, we developed a flow cytometry technique based on an all-optical measurement to measure nuclear mechanical properties by integrating Brillouin spectroscopy with microfluidics...
January 19, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28102305/structure-and-membrane-interactions-of-the-homodimeric-antibiotic-peptide-homotarsinin
#9
Rodrigo M Verly, Jarbas M Resende, Eduardo F C Junior, Mariana T Q de Magalhães, Carlos F C R Guimarães, Victor H O Munhoz, Marcelo Porto Bemquerer, Fábio C L Almeida, Marcelo M Santoro, Dorila Piló-Veloso, Burkhard Bechinger
Antimicrobial peptides (AMPs) from amphibian skin are valuable template structures to find new treatments against bacterial infections. This work describes for the first time the structure and membrane interactions of a homodimeric AMP. Homotarsinin, which was found in Phyllomedusa tarsius anurans, consists of two identical cystine-linked polypeptide chains each of 24 amino acid residues. The high-resolution structures of the monomeric and dimeric peptides were determined in aqueous buffers. The dimer exhibits a tightly packed coiled coil three-dimensional structure, keeping the hydrophobic residues screened from the aqueous environment...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28101963/extreme-biophysics-enzymes-under-pressure
#10
Qi Huang, Jocelyn M Rodgers, Russell J Hemley, Toshiko Ichiye
A critical question about piezophilic (pressure-loving) microbes is how their constituent molecules maintain function under high pressure. Here, factors are examined that may lead to the increased activity under pressure in dihydrofolate reductase from the piezophilic Moritella profunda compared to the homologous enzyme from the mesophilic Escherichia coli. Molecular dynamics simulations are performed at various temperatures and pressures to examine how pressure affects the flexibility of the enzymes from these two microbes, since both stability and flexibility are necessary for enzyme activity...
January 19, 2017: Journal of Computational Chemistry
https://www.readbyqxmd.com/read/28101869/fibrin-formation-structure-and-properties
#11
John W Weisel, Rustem I Litvinov
Fibrinogen and fibrin are essential for hemostasis and are major factors in thrombosis, wound healing, and several other biological functions and pathological conditions. The X-ray crystallographic structure of major parts of fibrin(ogen), together with computational reconstructions of missing portions and numerous biochemical and biophysical studies, have provided a wealth of data to interpret molecular mechanisms of fibrin formation, its organization, and properties. On cleavage of fibrinopeptides by thrombin, fibrinogen is converted to fibrin monomers, which interact via knobs exposed by fibrinopeptide removal in the central region, with holes always exposed at the ends of the molecules...
2017: Sub-cellular Biochemistry
https://www.readbyqxmd.com/read/28101250/is-phosphatidylglycerol-essential-for-terrestrial-life
#12
REVIEW
Samuel Furse
Lipids are of increasing importance in understanding biological systems. Lipids carrying an anionic charge are noted in particular for their electrostatic interactions with both proteins and divalent cations. However, the biological, analytical, chemical and biophysical data of such species are rarely considered together, limiting our ability to assess the true role of such lipids in vivo. In this review, evidence from a range of studies about the lipid phosphatidylglycerol is considered. This evidence supports the conclusions that this lipid is ubiquitous in living systems and generally of low abundance but probably fundamental for terrestrial life...
January 2017: Journal of Chemical Biology
https://www.readbyqxmd.com/read/28100828/an-integrated-modelling-framework-for-neural-circuits-with-multiple-neuromodulators
#13
Alok Joshi, Vahab Youssofzadeh, Vinith Vemana, T M McGinnity, Girijesh Prasad, KongFatt Wong-Lin
Neuromodulators are endogenous neurochemicals that regulate biophysical and biochemical processes, which control brain function and behaviour, and are often the targets of neuropharmacological drugs. Neuromodulator effects are generally complex partly owing to the involvement of broad innervation, co-release of neuromodulators, complex intra- and extrasynaptic mechanism, existence of multiple receptor subtypes and high interconnectivity within the brain. In this work, we propose an efficient yet sufficiently realistic computational neural modelling framework to study some of these complex behaviours...
January 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28100817/mechanical-sensitivity-and-the-dynamics-of-evolutionary-rate-shifts-in-biomechanical-systems
#14
Martha M Muñoz, Philip S L Anderson, S N Patek
The influence of biophysical relationships on rates of morphological evolution is a cornerstone of evolutionary theory. Mechanical sensitivity-the correlation strength between mechanical output and the system's underlying morphological components-is thought to impact the evolutionary dynamics of form-function relationships, yet has rarely been examined. Here, we compare the evolutionary rates of the mechanical components of the four-bar linkage system in the raptorial appendage of mantis shrimp (Order Stomatopoda)...
January 25, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28100490/amino-terminal-domains-of-kainate-receptors-determine-the-differential-dependence-on-neto-auxiliary-subunits-for-trafficking
#15
Nengyin Sheng, Yun Stone Shi, Roger A Nicoll
The kainate receptor (KAR), a subtype of glutamate receptor, mediates excitatory synaptic responses at a subset of glutamatergic synapses. However, the molecular mechanisms underlying the trafficking of its different subunits are poorly understood. Here we use the CA1 hippocampal pyramidal cell, which lacks KAR-mediated synaptic currents, as a null background to determine the minimal requirements for the extrasynaptic and synaptic expression of the GluK2 subunit. We find that the GluK2 receptor itself, in contrast to GluK1, traffics to the neuronal surface and synapse efficiently and the auxiliary subunits Neto1 and Neto2 caused no further enhancement of these two trafficking processes...
January 18, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28099848/biophysical-attributes-of-cpg-presentation-control-tlr9-signaling-to-differentially-polarize-systemic-immune-responses
#16
Jardin A Leleux, Pallab Pradhan, Krishnendu Roy
It is currently unknown whether and how mammalian pathogen recognition receptors (PRRs) respond to biophysical patterns of pathogen-associated molecular danger signals. Using synthetic pathogen-like particles (PLPs) that mimic physical properties of bacteria or large viruses, we have discovered that the quality and quantity of Toll-like receptor 9 (TLR9) signaling by CpG in mouse dendritic cells (mDCs) are uniquely dependent on biophysical attributes; specifically, the surface density of CpG and size of the presenting PLP...
January 17, 2017: Cell Reports
https://www.readbyqxmd.com/read/28099727/association-of-biochemical-markers-with-the-severity-of-pre-eclampsia
#17
Ahmed M Maged, Gamal Aid, Nehal Bassiouny, Doaa S Eldin, Sherif Dahab, Nevein K Ghamry
OBJECTIVE: To assess the association between pre-eclampsia severity and biochemical and ultrasonography markers. METHODS: A retrospective study was undertaken of women with severe pre-eclampsia (group 1, n=90), mild pre-eclampsia (group 2, n=90), or a normal pregnancy (group 3, n=90) who attended a hospital in Egypt in October 2013-April 2015. Associations between pre-eclampsia and biochemical, cardiotocography, and ultrasonography markers were investigated. RESULTS: There were significant differences between the groups in C-reactive protein (331...
February 2017: International Journal of Gynaecology and Obstetrics
https://www.readbyqxmd.com/read/28098556/genetic-defects-in-%C3%AE-spectrin-and-tau-sensitize-c-elegans-axons-to-movement-induced-damage-via-torque-tension-coupling
#18
Michael Krieg, Jan Stühmer, Juan G Cueva, Richard Fetter, Kerri A Spliker, Daniel Cremers, Kang Shen, Alexander R Dunn, Miriam B Goodman
Our bodies are in constant motion and so are the neurons that invade each tissue. Motion-induced neuron deformation and damage are associated with several neurodegenerative conditions. Here, we investigated the question of how the neuronal cytoskeleton protects axons and dendrites from mechanical stress, exploiting mutations in UNC-70 β-spectrin, PTL-1 tau/MAP2-like and MEC-7 β-tubulin proteins in Caenorhabditis elegans. We found that mechanical stress induces supercoils and plectonemes in the sensory axons of spectrin and tau double mutants...
January 18, 2017: ELife
https://www.readbyqxmd.com/read/28098306/effective-viscosity-and-dynamics-of-spreading-epithelia-a-solvable-model
#19
C Blanch-Mercader, R Vincent, E Bazellières, X Serra-Picamal, X Trepat, J Casademunt
Collective cell migration in spreading epithelia in controlled environments has become a landmark in our current understanding of fundamental biophysical processes in development, regeneration, wound healing or cancer. Epithelial monolayers are treated as thin layers of a viscous fluid that exert active traction forces on the substrate. The model is exactly solvable and shows a broad range of applicabilities for the quantitative analysis and interpretation of force microscopy data of monolayers from a variety of experiments and cell lines...
January 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28098278/understanding-the-connection-between-conformational-changes-of-peptides-and-equilibrium-thermal-fluctuations
#20
Miguel A Soler, José Zúñiga, Alberto Requena, Adolfo Bastida
Despite the increasing evidence that conformational transitions in peptides and proteins are driven by specific vibrational energy pathways along the molecule, the current experimental techniques of analysis do as yet not allow to study these biophysical processes in terms of anisotropic energy flows. Computational methods offer a complementary approach to obtain a more detailed understanding of the vibrational and conformational dynamics of these systems. Accordingly, in this work we investigate jointly the vibrational energy distribution and the conformational dynamics of trialanine peptide in water solution at room temperature by applying the Instantaneous Normal Mode analysis to the results derived from equilibrium molecular dynamics simulations...
January 18, 2017: Physical Chemistry Chemical Physics: PCCP
keyword
keyword
7837
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"