Small iminium ions block gramicidin channels in lipid bilayers.

abstract：:Formation of amyloid oligomers, the most toxic species of amyloids in degenerative diseases, is critically coupled to the interplay with surrounding water. The hydrophobic force driving the oligomerization causes water removal from interfaces, changing the surface-hydration properties. Here, we show that such effects ...

journal_title：Biophysical journal

authors： Walton JH,Berry RS,Despa F

更新日期：2011-05-04 00:00:00

abstract：:Red blood cells aggregate face-to-face to form long, cylindrical, straight chains and sometimes branched structures called rouleaux. Here we extend a kinetic model developed by R. W. Samsel and A. S. Perelson (1982, Biophys. J. 37:493-514) to include both the formation and dissociation of rouleaux. We examine thermody...

journal_title：Biophysical journal

authors： Samsel RW,Perelson AS

更新日期：1984-04-01 00:00:00

abstract：:Polarized Fourier transform infrared spectroscopy has been used to study the structure of purple membrane from Halobacterium halobium. Membranes were oriented by drying a suspension of membrane fragments onto Irtran-4 slides. Dichroism measurements of the amide I, II and A peaks were used to find the average spatial o...

journal_title：Biophysical journal

authors： Rothschild KJ,Clark NA

更新日期：1979-03-01 00:00:00

abstract：:The effect of weak, nonspecific interaction between molecules confined within restricted elements of volume ("pores") and the boundary surfaces of the pore, upon the reactivity and physical state of the confined molecules, is explored by means of simple models. A confined molecule is represented by a rectangular paral...

journal_title：Biophysical journal

authors： Minton AP

更新日期：1995-04-01 00:00:00

abstract：:Protein aggregation is linked to more than 30 human pathologies, including Alzheimer's and Parkinson's diseases. Since small oligomers that form at the beginning of the fibrillation process probably are the most toxic elements, therapeutic strategies involving fibril fragmentation could be detrimental. An alternative ...

journal_title：Biophysical journal

authors： Pagano RS,López Medus M,Gómez GE,Couto PM,Labanda MS,Landolfo L,D'Alessio C,Caramelo JJ

更新日期：2014-08-05 00:00:00

abstract：:The biophysical properties and cellular distribution of ion channels largely determine the input/output relationships of electrically excitable cells. A variety of patch pipette voltage clamp techniques are available to characterize ionic currents. However, when used by themselves, such techniques are not well suited ...

journal_title：Biophysical journal

authors： Anson BD,Roberts WM

更新日期：1998-06-01 00:00:00

abstract：:The present article considers the influence of heterogeneity in a mobile analyte or in an immobilized ligand population on the surface binding kinetics and equilibrium isotherms. We describe strategies for solving the inverse problem of calculating two-dimensional distributions of rate and affinity constants from expe...

journal_title：Biophysical journal

authors： Svitel J,Balbo A,Mariuzza RA,Gonzales NR,Schuck P

更新日期：2003-06-01 00:00:00

abstract：:A simulation of the function of the human heart and heart muscle has been developed in the form of a digital computer code. For a given set of values for the input variables, realistic values of the cardiac output variables are predicted. A detailed discussion of the simulation and some results obtained from its appli...

journal_title：Biophysical journal

authors： Hanna WT

更新日期：1973-07-01 00:00:00

abstract：:Biophysical understanding of membrane domains requires accurate knowledge of their structural details and elasticity. We report on a global small angle x-ray scattering data analysis technique for coexisting liquid-ordered (Lo) and liquid-disordered (Ld) domains in fully hydrated multilamellar vesicles. This enabled t...

journal_title：Biophysical journal

authors： Heftberger P,Kollmitzer B,Rieder AA,Amenitsch H,Pabst G

更新日期：2015-02-17 00:00:00

abstract：:Conserved active-site elements in myosins and other P-loop NTPases play critical roles in nucleotide binding and hydrolysis; however, the mechanisms of allosteric communication among these mechanoenzymes remain unresolved. In this work we introduced the E442A mutation, which abrogates a salt-bridge between switch I an...

journal_title：Biophysical journal

authors： Trivedi DV,David C,Jacobs DJ,Yengo CM

更新日期：2012-06-06 00:00:00

abstract：:Understanding the mechanism of saturated fatty acid-induced hepatocyte toxicity may provide insight into cures for diseases such as obesity-associated cirrhosis. Trehalose, a nonreducing disaccharide shown to protect proteins and cellular membranes from inactivation or denaturation caused by different stress condition...

journal_title：Biophysical journal

authors： Leekumjorn S,Wu Y,Sum AK,Chan C

更新日期：2008-04-01 00:00:00

abstract：:Neutrophils rely on rapid changes in morphology to ward off invaders. Time-resolved dynamics of spreading human neutrophils after activation by the chemoattractant fMLF (formyl methionyl leucyl phenylalanine) was observed by RICM (reflection interference contrast microscopy). An image-processing algorithm was develope...

journal_title：Biophysical journal

authors： Sengupta K,Aranda-Espinoza H,Smith L,Janmey P,Hammer D

更新日期：2006-12-15 00:00:00

abstract：:Recent NMR structural characterization studies showed that a seven-residue segment (FKKGERL) from the src SH3 domain adopts the nativelike diverging type II beta-turn in aqueous solution in support of the prediction based on the I-sites library of sequence structural motifs. We study the conformational variability and...

journal_title：Biophysical journal

authors： Gnanakaran S,Garcia AE

更新日期：2003-03-01 00:00:00

abstract：:A refined mesoscopic model for the cumulative effect of repulsive excluded volume protein-protein interaction and attractive protein-surface interaction upon the properties of a trace protein capable of fiber formation is presented. The model predicts that very small changes in the magnitude of bulk volume occupancy o...

journal_title：Biophysical journal

authors： Minton AP

更新日期：2019-11-05 00:00:00

abstract：:An innovative method is presented to measure the mechanical driving point impedance of biological structures up to at least 40 kHz. The technique employs an atomic force cantilever with a ferromagnetic coating and an external magnetic field to apply a calibrated force to the cantilever. Measurement of the resulting ca...

journal_title：Biophysical journal

authors： Scherer MP,Gummer AW

更新日期：2004-08-01 00:00:00

abstract：:Measurements were made of exchange rates of oxygen, carbon dioxide, and krypton-85 with blood at 37.5 degrees C. Gas transfer took place across a 1 mil silicone rubber membrane. The blood was in a rotating disk boundary layer flow, and the controlling resistance to transfer was the concentration boundary layer. Measur...

journal_title：Biophysical journal

authors： Spaeth EE,Friedlander SK

更新日期：1967-11-01 00:00:00

abstract：:To investigate the mechanisms by which vesicles of pulmonary surfactant adsorb to an air-liquid interface, we measured the effect of different phospholipids and of their concentration both in the subphase and at the interface on this process. Adsorbing vesicles contained the hydrophobic surfactant proteins mixed with ...

journal_title：Biophysical journal

authors： Walters RW,Jenq RR,Hall SB

更新日期：2000-01-01 00:00:00

abstract：:Lateral organization of cholesterol in dioleoyl-phosphatidylcholine (DOPC) lipid bilayers at high cholesterol concentration (>45 mol%) was investigated using steady-state fluorescence anisotropy and fluorescent resonance energy transfer techniques. The recently devised Low Temperature Trap method was used to prepare c...

journal_title：Biophysical journal

authors： Parker A,Miles K,Cheng KH,Huang J

更新日期：2004-03-01 00:00:00

abstract：:Molecular dynamics simulations of protein tyrosine phosphatase 1B (PTP1B) complexed with the phosphorylated peptide substrate DADEpYL and the free substrate have been conducted to investigate 1) the physical forces involved in substrate-protein interactions, 2) the importance of enzyme and substrate flexibility for bi...

journal_title：Biophysical journal

authors： Peters GH,Frimurer TM,Andersen JN,Olsen OH

更新日期：2000-05-01 00:00:00

abstract：:Actin labeled at Gln-41 with dansyl ethylenediamine (DED) via transglutaminase reaction was used for monitoring the interaction of myosin subfragment 1 (S1) with the His-40-Gly-42 site in the 38-52 loop on F-actin. Proteolytic digestions of F-actin with subtilisin and trypsin, and acto-S1 ATPase measurements on heat-t...

journal_title：Biophysical journal

authors： Kim E,Miller CJ,Motoki M,Seguro K,Muhlrad A,Reisler E

更新日期：1996-03-01 00:00:00

abstract：:A model is presented for the steric interaction between a plasma membrane protein and the membrane cytoskeleton in the human erythrocyte. The cytoskeleton is treated as a network of polymer chains attached to a flat bilayer, and the membrane protein is a hemisphere of effective radius R(e) with center on the bilayer e...

journal_title：Biophysical journal

authors： Boal DH,Boey SK

更新日期：1995-08-01 00:00:00

abstract：:Atomic force microscopy (AFM) can be used to probe the mechanics of molecular recognition between surfaces. In the application known as "chemical force" microscopy (CFM), a chemically modified AFM tip probes a surface through chemical recognition. When modified with a biological ligand or receptor, the AFM tip can dis...

journal_title：Biophysical journal

authors： Mazzola LT,Frank CW,Fodor SP,Mosher C,Lartius R,Henderson E

更新日期：1999-06-01 00:00:00

abstract：:Fluorescence lifetimes of dimeric rabbit muscle creatine kinase specifically dansylated at both active sites and the homologous monomeric lobster muscle arginine kinase singly dansylated were determined using phase-modulation methods with global analysis of overdetermined data sets. For both proteins, the data is adeq...

journal_title：Biophysical journal

authors： Grossman SH

更新日期：1991-03-01 00:00:00

abstract：:The current rapid expansion of biological knowledge offers a great opportunity to rationally engineer biological systems that respond to signals such as light and chemical inducers by producing specific proteins. Turning on and off the production of proteins on demand holds great promise for creating significant biote...

journal_title：Biophysical journal

authors： Tuttle LM,Salis H,Tomshine J,Kaznessis YN

更新日期：2005-12-01 00:00:00

abstract：:The structure of the Bowman-Birk inhibitor from Vigna unguiculata seeds (BTCI) in complex with beta-trypsin was solved and refined at 1.55 A to a crystallographic R(factor) of 0.154 and R(free) of 0.169, and represents the highest resolution for a Bowman-Birk inhibitor structure to date. The BTCI-trypsin interface is ...

journal_title：Biophysical journal

authors： Barbosa JA,Silva LP,Teles RC,Esteves GF,Azevedo RB,Ventura MM,de Freitas SM

更新日期：2007-03-01 00:00:00

abstract：:Two isoforms of the sarcoplasmic reticulum Ca2+ release channel (ryanodine receptor or RYR) are expressed together in the skeletal muscles of most vertebrates. We have studied physiological properties of the two isoforms (alpha and beta) by comparing SR preparations from specialized fish muscles that express the alpha...

journal_title：Biophysical journal

authors： O'Brien J,Valdivia HH,Block BA

更新日期：1995-02-01 00:00:00

abstract：:Thymine dimers were irradiated in aqueous solution with (60)Co gamma-rays in N(2) or O(2). Thymine and unidentified non-UV-absorbing products appeared. The thymine was identified by spectrophotometry, chromatography, and ability to support the growth of Escherichia coli 15 T(-). Residual dimer was determined by a UV-r...

journal_title：Biophysical journal

authors： Deering RA,Snipes W

更新日期：1968-03-01 00:00:00

abstract：:The thermal stability of a Schizolobium parahyba chymotrypsin inhibitor (SPCI) as a function of pH has been investigated using fluorescence, circular dichroism, and differential scanning calorimetry (DSC). The thermodynamic parameters derived from all methods are remarkably similar and strongly suggest the high stabil...

journal_title：Biophysical journal

authors： Teles RC,Calderon Lde A,Medrano FJ,Barbosa JA,Guimarães BG,Santoro MM,de Freitas SM

更新日期：2005-05-01 00:00:00

abstract：:A novel combined approach of molecular dynamics (MD) and Monte Carlo simulations is developed to calculate various free-volume distributions as a function of position in a lipid bilayer membrane at 323 K. The model bilayer consists of 2 x 100 chain molecules with each chain molecule having 15 carbon segments and one h...

journal_title：Biophysical journal

authors： Xiang TX

更新日期：1993-09-01 00:00:00

abstract：:A simple formula for the expansion rate U of the bilayer membrane perimeter was derived by the solution of the hydrodynamic and the Laplace equations at small rates and small contact angles: U = theta delta/6 micron ln (h/e 3/2 h0), where theta is the equilibrium contact angle between the bilayer membrane and the Plat...

journal_title：Biophysical journal

authors： Dimitrov DS

更新日期：1981-10-01 00:00:00