Oligomerization of membrane-bound diphtheria toxin (CRM197) facilitates a transition to the open form and deep insertion.

abstract：:Structures of truncated versions of the influenza A virus M2 proton channel have been determined recently by x-ray crystallography in the open conformation of the channel, and by NMR in the closed state. The structures differ in the position of the bound inhibitors. The x-ray structure shows a single amantadine molecu...

journal_title：Biophysical journal

authors： Chuang GY,Kozakov D,Brenke R,Beglov D,Guarnieri F,Vajda S

更新日期：2009-11-18 00:00:00

abstract：:Cardiac excitation-contraction coupling is initialized by the release of Ca from the sarcoplasmic reticulum (SR) in response to a sudden increase in local cytosolic [Ca] ([Ca]i) within the junctional cleft. We have tested the hypothesis that functional ryanodine receptor (RyR) regulation plays a major role in the regu...

journal_title：Biophysical journal

authors： Shannon TR,Wang F,Bers DM

更新日期：2005-12-01 00:00:00

abstract：:The prion protein (PrP), widely recognized to misfold into the causative agent of the transmissible spongiform encephalopathies, has previously been shown to bind to lipid membranes with binding influenced by both membrane composition and pH. Aside from the misfolding events associated with prion pathogenesis, PrP can...

journal_title：Biophysical journal

authors： Le Brun AP,Haigh CL,Drew SC,James M,Boland MP,Collins SJ

更新日期：2014-11-18 00:00:00

abstract：:Sarcomere lengths, cell widths, indices of stiffness, and striation pattern uniformity were determined from radially compressed isolated adult cardiac myocytes from the rat. Single cells were bathed in a series of relaxing solutions containing 0-15% concentrations of nonpenetrating long chain polymers PVP-40 and dextr...

journal_title：Biophysical journal

authors： Roos KP,Brady AJ

更新日期：1990-11-01 00:00:00

abstract：:We present a new method for the determination of structural parameters in biological membranes. Recording the continuous scattering of heavy-atom labeled membranes and applying elementary Fourier methods we obtain the scattering of the heavy-atom distribution alone. The details of this distribution are explored by dev...

journal_title：Biophysical journal

authors： Stamatoff J,Bilash T,Ching Y,Eisenberger P

更新日期：1979-12-01 00:00:00

abstract：:The stoichiometric matrix, S, represents a mapping of reaction rate vectors into a space of concentration time derivatives. The left null space of the stoichiometric matrix contains the dynamic invariants: a combination of concentration variables, referred to as metabolic pools, whose total concentration does not chan...

journal_title：Biophysical journal

authors： Famili I,Palsson BO

更新日期：2003-07-01 00:00:00

abstract：:A growth cone is a motile structure at the tips of axons that is driven by the actin network and guides axon extension. Low actin adhesion to the substrate creates a stationary actin treadmill that allows leading-edge protrusion when adhesion increases in response to guidance cues. We use experimental measurements in ...

journal_title：Biophysical journal

authors： Craig EM,Van Goor D,Forscher P,Mogilner A

更新日期：2012-04-04 00:00:00

abstract：:Mammalian sperm traverse several layers of egg vestments before fertilization can occur. The innermost vestment, the zona pellucida, is a glycoprotein shell, which captures and tethers the sperm before they penetrate it. We report here direct measurements of the force required to tether a motile human sperm as well as...

journal_title：Biophysical journal

authors： Baltz JM,Katz DF,Cone RA

更新日期：1988-10-01 00:00:00

abstract：:Equations describing the movement of sugars during induced uphill transport were derived on the assumption of a simple carrier transport mechanism and subjected to experimental verification. Since there was good agreement between the experimental points and the theoretical curves, no changes in the original postulates...

journal_title：Biophysical journal

authors： Miller DM

更新日期：1965-07-01 00:00:00

abstract：:The AXH domain of protein Ataxin 1 is thought to play a key role in the misfolding and aggregation pathway responsible for Spinocerebellar ataxia 1. For this reason, a molecular level understanding of AXH oligomerization pathway is crucial to elucidate the aggregation mechanism, which is thought to trigger the disease...

journal_title：Biophysical journal

authors： Grasso G,Morbiducci U,Massai D,Tuszynski JA,Danani A,Deriu MA

更新日期：2018-01-23 00:00:00

abstract：:The propagation of sounds and pulse waves within the cardiovascular system is subject to strong dissipative mechanisms. To investigate the effects of blood viscosity on dissipation as well as dispersion of small waves in arteries and veins, a parametric study has been carried out. A linearized analysis of axisymmetric...

journal_title：Biophysical journal

authors： Jones E,Anliker M,Chang ID

更新日期：1971-12-01 00:00:00

abstract：:Endophilins are SH3- and BAR domain-containing proteins implicated in membrane remodeling and vesicle formation. Endophilins A1 and A2 promote the budding of endocytic vesicles from the plasma membrane, whereas endophilin B1 has been implicated in vesicle budding from intracellular organelles, including the trans-Golg...

journal_title：Biophysical journal

authors： Li J,Barylko B,Eichorst JP,Mueller JD,Albanesi JP,Chen Y

更新日期：2016-08-09 00:00:00

abstract：:Dual-trap optical tweezers are often used in high-resolution measurements in single-molecule biophysics. Such measurements can be hindered by the presence of extraneous noise sources, the most prominent of which is the coupling of fluctuations along different spatial directions, which may affect any optical tweezers s...

journal_title：Biophysical journal

authors： Ribezzi-Crivellari M,Ritort F

更新日期：2012-11-07 00:00:00

abstract：:In a pure fluid-phase lipid, the dependence of the lateral diffusion coefficient on the size of the diffusing particle may be obtained from the Saffman-Delbrück equation or the free-volume model. When diffusion is obstructed by immobile proteins or domains of gel-phase lipids, the obstacles yield an additional contrib...

journal_title：Biophysical journal

authors： Saxton MJ

更新日期：1993-04-01 00:00:00

abstract：:The mathematics of the binomial model for quantal neurotransmitter release is considered in general terms, to explore what information might be extractable from statistical aspects of data. For an array of N statistically independent release sites, each with a release probability p, the compound binomial always pertai...

journal_title：Biophysical journal

authors： Quastel DM

更新日期：1997-02-01 00:00:00

abstract：:Muscle contraction occurs as the result of actin-myosin interaction, which is mediated by the intermolecular forces exerted at the actin-myosin interface. To obtain information about the nature of these intermolecular forces, we tested the sensitivity of various contractile parameters of skinned skeletal muscle fibers...

journal_title：Biophysical journal

authors： Iwamoto H

更新日期：2000-06-01 00:00:00

abstract：:Octyl-beta-thioglucopyranoside (octyl thioglucoside, OTG) is a nonionic surfactant used for the purification, reconstitution, and crystallization of membrane proteins. The thermodynamic properties of the OTG-membrane partition equilibrium are not known and have been investigated here with high-sensitivity titration ca...

journal_title：Biophysical journal

authors： Wenk MR,Seelig J

更新日期：1997-11-01 00:00:00

abstract：:To determine if hydrophobic surfactant proteins affect the stability of pulmonary surfactant monolayers at an air/water interface, the studies reported here compared the kinetics of collapse for the complete set of lipids in calf surfactant with and without the proteins. Monomolecular films spread at the surface of ca...

journal_title：Biophysical journal

authors： Lhert F,Yan W,Biswas SC,Hall SB

更新日期：2007-12-15 00:00:00

abstract：:Physical origin of DNA condensation by multivalent cations remains unsettled. Here, we report quantitative studies of how one DNA-condensing ion (Cobalt(3+) Hexammine, or Co(3+)Hex) and one nonDNA-condensing ion (Mg(2+)) compete within the interstitial space in spontaneously condensed DNA arrays. As the ion concentrat...

journal_title：Biophysical journal

authors： Qiu X,Giannini J,Howell SC,Xia Q,Ke F,Andresen K

更新日期：2013-08-20 00:00:00

abstract：:The refractive indices, water content, and volume of wet-spun films of Na-hyaluronate have been measured as a function of relative humidity (rh). These data are used with the Lorentz-Lorenz formula to determine the optical polarizabilities of Na-hyaluronate parallel and perpendicular to the helical axis. The analysis ...

journal_title：Biophysical journal

authors： Flowers MR,Marlow RL,Lee SA,Lavalle N,Rupprecht A

更新日期：1992-08-01 00:00:00

abstract：:The structure of the unusually long (∼100 amino-acid residues) N-terminal domain of the light-harvesting protein CP29 of plants is not defined in the crystal structure of this membrane protein. We studied the N-terminus using two electron paramagnetic resonance (EPR) approaches: the rotational diffusion of spin labels...

journal_title：Biophysical journal

authors： Shabestari MH,Wolfs CJ,Spruijt RB,van Amerongen H,Huber M

更新日期：2014-03-18 00:00:00

abstract：:In permeabilized single fibers of fast (psoas) and slow (soleus) muscle from the rabbit, the effect of pH on isometric myofibrillar ATPase activity and force was studied at 15 degrees C, in the pH range 6.4-7.9. ATPase activity was measured photometrically by enzymatic coupling of the regeneration of ATP to the oxidat...

journal_title：Biophysical journal

authors： Potma EJ,van Graas IA,Stienen GJ

更新日期：1994-12-01 00:00:00

abstract：:Cubic insulin crystals contain a binding site for monovalent cations in a cavity of the crystal dyad in which the bound cation is ligated by protein atomic dipoles and water molecules. These types of interaction are analogous to interactions that occur in small cation-selective carrier and channel molecules. X-ray dif...

journal_title：Biophysical journal

authors： Badger J,Kapulsky A,Gursky O,Bhyravbhatla B,Caspar DL

更新日期：1994-02-01 00:00:00

abstract：:It is accepted that bicarbonate reabsorption in the proximal tubule is mediated by H+ secretion, but several aspects of this process have remained controversial. To examine some of these issues, we have developed a model that allows for spatial variations in the concentrations of CO2, HCO3-, and H2CO3 within the tubul...

journal_title：Biophysical journal

authors： Wang KW,Deen WM

更新日期：1980-08-01 00:00:00

abstract：:Magic-angle spinning nuclear magnetic resonance is well suited for the study of membrane proteins in the nativelike lipid environment. However, the natural cellular membrane is invariably more complex than the proteoliposomes most often used for solid-state NMR (SSNMR) studies, and differences may affect the structure...

journal_title：Biophysical journal

authors： Ward ME,Wang S,Munro R,Ritz E,Hung I,Gor'kov PL,Jiang Y,Liang H,Brown LS,Ladizhansky V

更新日期：2015-04-07 00:00:00

abstract：:High speed cinemicrographs were made of sea urchin sperm at temperatures varying from 22 to 6 degrees C. Apparatus, combining a television camera and a video digitizer, was constructed to scan individual flagellar images and to digitize the flagellar waveforms. With appropriate smoothing and averaging procedures, the ...

journal_title：Biophysical journal

authors： Rikmenspoel R,Isles CA

更新日期：1985-03-01 00:00:00

abstract：:Negatively charged phospholipids are an important component of biological membranes. The thermodynamic parameters governing self-assembly of anionic phospholipids are deduced here from isothermal titration calorimetry. Heats of demicellization were determined for dioctanoyl phosphatidylglycerol (PG) and phosphatidylse...

journal_title：Biophysical journal

authors： Marsh D

更新日期：2012-03-07 00:00:00

abstract：:Neal and Cunningham (Neal, M. J., and J. R. Cunningham. 1995. J. Physiol. (Lond.). 482:363-372) showed that GABA(B) agonists and glycinergic antagonists enhance the light-evoked release of retinal acetylcholine. They proposed that glycinergic cells inhibit the cholinergic Starburst amacrine cells and are in turn inhib...

journal_title：Biophysical journal

authors： Grzywacz NM,Zucker CL

更新日期：2006-07-15 00:00:00

abstract：:To explain the effect of profilin on actin critical concentration in a manner consistent with thermodynamic constraints and available experimental data, we built a thermodynamically rigorous model of actin steady-state dynamics in the presence of profilin. We analyzed previously published mechanisms theoretically and ...

journal_title：Biophysical journal

authors： Yarmola EG,Dranishnikov DA,Bubb MR

更新日期：2008-12-15 00:00:00

abstract：:In adherent and motile neutrophils NAD(P)H concentration, flavoprotein redox potential, and production of reactive oxygen species and nitric oxide, are all periodic and exhibit defined phase relationships to an underlying metabolic oscillation of approximately 20 s. Utilizing fluorescence microscopy, we have shown in ...

journal_title：Biophysical journal

authors： Rosenspire AJ,Kindzelskii AL,Simon BJ,Petty HR

更新日期：2005-05-01 00:00:00