Sizing membrane pores in lipid vesicles by leakage of co-encapsulated markers: pore formation by melittin.

abstract：:Antibodies are key tools in biomedical research and medicine. Their binding properties are classically measured in solution and characterized by an affinity. However, in physiological conditions, antibodies can bridge an immune effector cell and an antigen-presenting cell, implying that mechanical forces may apply to ...

journal_title：Biophysical journal

authors： González C,Chames P,Kerfelec B,Baty D,Robert P,Limozin L

更新日期：2019-04-23 00:00:00

abstract：:Based on differences between the x-ray crystal structures of ligand-bound and unbound forms, the activation of the erythropoietin receptor (EPOR) was initially proposed to involve a cross-action scissorlike motion. However, the validity of the motions involved in the scissorlike model has been recently challenged. Her...

journal_title：Biophysical journal

authors： Corbett MSP,Mark AE,Poger D

更新日期：2017-02-28 00:00:00

abstract：:As normally studied, in the solid state or in solution, poly(beta-benzyl-L-aspartate) (PBLA) differs from the other helical polyamino acids in that its alpha-helical conformation is most stable in the left-handed rather than in the right-handed form. The slightly lower energy per residue for the left-handed form in PB...

journal_title：Biophysical journal

authors： Riou SA,Hsu SL,Stidham HD

更新日期：1998-11-01 00:00:00

abstract：:The nature of the mechanism limiting the velocity of ATP-induced unidirectional movements of actin-myosin filaments in vitro is considered. In the sliding process two types of "cyclic" interactions between myosin heads and actin are involved, i.e., productive and nonproductive. In the productive interaction, myosin he...

journal_title：Biophysical journal

authors： Tawada K,Sekimoto K

更新日期：1991-02-01 00:00:00

abstract：:Pure Michaelis-Menten enzymes have been studied (i.e., enzymes with a hyperbolic (S, V) behavior in a well-stirred solution). When such enzymes are associated with a structure in vitro, even in the simplest conceivable form (immobilization in a homogeneous gel), they can produce enzymic or transport reactions with man...

journal_title：Biophysical journal

authors： Vincent JC,Thellier M

更新日期：1983-01-01 00:00:00

abstract：:Starzak and Starzak (1978. IEEE Trans. Biomed. Eng. 25:201-204.) proposed that, in cyclic application of current and voltage-clamps, the fidelity of the match of the output current with the original stimulus could be used to measure the spatial uniformity of voltage in a membrane. However, they failed to find such a m...

journal_title：Biophysical journal

authors： Moore JW,Stockbridge N,Schiff SJ

更新日期：1982-12-01 00:00:00

abstract：:The determination of intracellular protein concentrations is a prerequisite for understanding protein interaction networks in systems biology. Today, protein quantification is based either on mass spectrometry, which requires large cell numbers and sophisticated measurement protocols, or on quantitative Western blotti...

journal_title：Biophysical journal

authors： Chung YD,Sinzinger MD,Bovee-Geurts P,Krause M,Dinkla S,Joosten I,Koopman WJ,Adjobo-Hermans MJ,Brock R

更新日期：2011-12-07 00:00:00

abstract：:Using polarography and suitable mathematical analysis, the oxygen permeability of an individual layer of a bilayered tissue may be determined if the oxygen consumption and permeability of the other layer are known. Results obtained on rabbit cornea indicate that the permeability of the epithelium is about four times t...

journal_title：Biophysical journal

authors： Freeman RD,Fatt I

更新日期：1972-03-01 00:00:00

abstract：:An attempt was made to confirm previous reports of resonant-like dielectric absorption of plasmid DNA in aqueous solutions at 1-10 GHz. The dielectric properties of the sample were measured using an automatic network analyzer with two different techniques. One technique used an open-ended coaxial probe immersed in the...

journal_title：Biophysical journal

authors： Foster KR,Epstein BR,Gealt MA

更新日期：1987-09-01 00:00:00

abstract：:The elastic theory of flexural waves in thin rods accurately predicts the velocity of flagellar bending waves over a wide range of viscosities. This shows that flagella behave as a purely mechanical system for the transmission of these waves. An evaluation of the total bending moment reveals that this moment occurs in...

journal_title：Biophysical journal

authors： Rikmenspoel R

更新日期：1971-05-01 00:00:00

abstract：:The glucocorticoid receptor (GR) is a steroid-hormone-activated transcription factor that modulates gene expression. Transcriptional regulation by the GR requires dynamic receptor binding to specific target sites located across the genome. This binding remodels the chromatin structure to allow interaction with other t...

journal_title：Biophysical journal

authors： Muratcioglu S,Presman DM,Pooley JR,Grøntved L,Hager GL,Nussinov R,Keskin O,Gursoy A

更新日期：2015-09-15 00:00:00

abstract：:We present a model of cell motility generated by actomyosin contraction of the cell cortex. We identify, analytically, dynamical instabilities of the cortex and show that they yield steady-state cortical flows, which, in turn, can induce cell migration in three-dimensional environments. This mechanism relies on the re...

journal_title：Biophysical journal

authors： Hawkins RJ,Poincloux R,Bénichou O,Piel M,Chavrier P,Voituriez R

更新日期：2011-09-07 00:00:00

abstract：:The mechanism for transport of divalent cations across phospholipid bilayers by the ionophore A23187 was investigated. The intrinsic fluorescence of the ionophore was used in equilibrium and rapid-mixing experiments as an indicator of ionophore environment and complexation with divalent cations. The neutral (protonate...

journal_title：Biophysical journal

authors： Kolber MA,Haynes DH

更新日期：1981-11-01 00:00:00

abstract：:This article shows that colchicine and taxol strongly influence the kinetics of L-type Ca channels in intact cardiac cells, and it suggests a mechanism for this action. It is known that colchicine disassociates microtubules into tubulin, and that taxol stabilizes microtubules. We have found that colchicine increases t...

journal_title：Biophysical journal

authors： Galli A,DeFelice LJ

更新日期：1994-12-01 00:00:00

abstract：:We modeled two different mechanisms, a shunting conductance and a slow sodium inactivation, to test whether they could modulate the active propagation of a train of action potentials in a dendritic tree. Computer simulations, using a compartmental model of a pyramidal neuron, suggest that each of these two mechanisms ...

journal_title：Biophysical journal

authors： Migliore M

更新日期：1996-11-01 00:00:00

abstract：:A structural model is suggested for axon membranes consisting of a double layer of lipid and phospholipid molecules in which the polar ends of certain phospholipids change their orientation and combining properties under the influence of an electric field. The phosphate groups act as ion exchange "gates" for the contr...

journal_title：Biophysical journal

authors： GOLDMANN DE

更新日期：1964-05-01 00:00:00

abstract：:Nucleoprotein filament formation by recombinases is central to homologous recombination. To follow this process, we used fluorescent human Rad51 recombinase to visualize the interactions with double-stranded DNA (dsDNA). Fluorescence imaging revealed that Rad51 filament formation on dsDNA initiates from multiple nucle...

journal_title：Biophysical journal

authors： Mameren Jv,Modesti M,Kanaar R,Wyman C,Wuite GJ,Peterman EJ

更新日期：2006-10-15 00:00:00

abstract：:The primary processes of the photochemical cycle of light-adapted bacteriorhodopsin (BR) were studied by various experimental techniques with a time resolution of 5 x 10(-13) s. The following results were obtained. (a) After optical excitation the first excited singlet state S(1) of bacteriorhodopsin is observed via i...

journal_title：Biophysical journal

authors： Polland HJ,Franz MA,Zinth W,Kaiser W,Kölling E,Oesterhelt D

更新日期：1986-03-01 00:00:00

abstract：:The diffusion of Ca as it converges to the external mouth of a Ca channel is examined. Diffusional limitation on Ca ions entering Ca channels during current flow, cause local extracellular Ca depletions. Such extracellular Ca depletions have been reported in cardiac muscle. The cardiac sarcolemma has a large number of...

journal_title：Biophysical journal

authors： Bers DM,Peskoff A

更新日期：1991-03-01 00:00:00

abstract：:Presented here is a quantitative model of the wrapping and unwrapping of the DNA around the histone core of the nucleosome that suggests a mechanism by which this transition can be controlled: alteration of the charge state of the globular histone core. The mechanism is relevant to several classes of posttranslational...

journal_title：Biophysical journal

authors： Fenley AT,Adams DA,Onufriev AV

更新日期：2010-09-08 00:00:00

abstract：:Stepwise two-photon excitation of chlorophyll a and b in the higher plant main light-harvesting complex (LHC II) and the minor complex CP29 (as well as in organic solution) with 100-fs pulses in the Q(y) region results in a weak blue fluorescence. The dependence of the spectral shape of the blue fluorescence on excita...

journal_title：Biophysical journal

authors： Leupold D,Teuchner K,Ehlert J,Irrgang KD,Renger G,Lokstein H

更新日期：2002-03-01 00:00:00

abstract：:Computer-assisted motion analysis coupled to flash photolysis of caged chemoeffectors provides a means for time-resolved analysis of bacterial chemotaxis. Escherichia coli taxis toward the amino acid attractant L-aspartate is mediated by the Tar receptor. The physiology of this response, as well as Tar structure and b...

journal_title：Biophysical journal

authors： Jasuja R,Keyoung J,Reid GP,Trentham DR,Khan S

更新日期：1999-03-01 00:00:00

abstract：:Membrane domains known as rafts are rich in cholesterol and sphingolipids, and are thought to be thicker than the surrounding membrane. If so, monolayers should elastically deform so as to avoid exposure of hydrophobic surfaces to water at the raft boundary. We calculated the energy of splay and tilt deformations nece...

journal_title：Biophysical journal

authors： Kuzmin PI,Akimov SA,Chizmadzhev YA,Zimmerberg J,Cohen FS

更新日期：2005-02-01 00:00:00

abstract：:Single epithelial Na+ channels incorporated into planar lipid bilayers were studied to determine the effects of Na concentration on its own conductance. Amiloride-sensitive Na+ channels were obtained from apical membrane vesicles made from A6 cells, a continuous epithelial cell-line derived from amphibian kidney. Sing...

journal_title：Biophysical journal

authors： Olans L,Sariban-Sohraby S,Benos DJ

更新日期：1984-12-01 00:00:00

abstract：:Calcium is essential for many biological processes involved in cellular motility. However, the pathway by which calcium influences motility, in processes such as muscle contraction and neuronal growth, is often indirect and complex. We establish a simple and direct mechanochemical link that shows how calcium quantitat...

journal_title：Biophysical journal

authors： Tam BK,Shin JH,Pfeiffer E,Matsudaira P,Mahadevan L

更新日期：2009-08-19 00:00:00

abstract：:The conformational states of Escherichia coli Rep helicase undergoing ATP hydrolysis while bound to a partial-duplex DNA (pdDNA) were studied using single-molecule FRET. Crystallographic studies showed that Rep bound to single-stranded DNA can exist in open and closed conformations that differ in the orientation of th...

journal_title：Biophysical journal

authors： Balci H,Arslan S,Myong S,Lohman TM,Ha T

更新日期：2011-08-17 00:00:00

abstract：:DNA release from lipoplexes is an essential step during lipofection and is probably a result of charge neutralization by cellular anionic lipids. As a model system to test this possibility, fluorescence resonance energy transfer between DNA and lipid covalently labeled with Cy3 and BODIPY, respectively, was used to mo...

journal_title：Biophysical journal

authors： Tarahovsky YS,Koynova R,MacDonald RC

更新日期：2004-08-01 00:00:00

abstract：:Because of their remarkable ability to depress the freezing point of aqueous solutions, antifreeze proteins (AFPs) play a critical role in helping many organisms survive subzero temperatures. The beta-helical insect AFP structures solved to date, consisting of multiple repeating circular loops or coils, are perhaps th...

journal_title：Biophysical journal

authors： Liu K,Jia Z,Chen G,Tung C,Liu R

更新日期：2005-02-01 00:00:00

abstract：:The unfolding and folding of protein barnase has been extensively investigated in bulk conditions under the effect of denaturant and temperature. These experiments provided information about structural and kinetic features of both the native and the unfolded states of the protein, and debates about the possible existe...

journal_title：Biophysical journal

authors： Alemany A,Rey-Serra B,Frutos S,Cecconi C,Ritort F

更新日期：2016-01-05 00:00:00

abstract：:We describe a puffing method for changing solutions near one surface of lipid bilayers that allows simultaneous measurement of channel activity and extent of solution change at the bilayer surface. Ion adsorption to the lipid headgroups and screening of the bilayer surface charge by mobile ions provided a convenient p...

journal_title：Biophysical journal

authors： Laver DR,Curtis BA

更新日期：1996-08-01 00:00:00