Early picosecond events in the photocycle of bacteriorhodopsin.

abstract：:High-resolution measurement of membrane capacitance in the whole-cell-recording configuration can be used to detect small changes in membrane surface area that accompany exocytosis and endocytosis. We have investigated the noise of membrane capacitance measurements to determine the fundamental limits of resolution in ...

journal_title：Biophysical journal

authors： Chen P,Gillis KD

更新日期：2000-10-01 00:00:00

abstract：:In diseases of the brain, the distribution and properties of ion channels display deviations from healthy control subjects. We studied three cases of ion channel alteration related to epileptogenesis. The first case of ion channel alteration represents an enhanced sodium current, the second case addresses the downregu...

journal_title：Biophysical journal

authors： Tigerholm J,Fransén E

更新日期：2011-10-19 00:00:00

abstract：:This paper describes a molecular dynamics and molecular mechanics study of the solvation and selectivity of the narrow pore and vestibule region of a model-built structure for the voltage-gated sodium channel. The particular structure used was one proposed by Guy and Durell. However, many of the features we saw would ...

journal_title：Biophysical journal

authors： Singh C,Sankararamakrishnan R,Subramaniam S,Jakobsson E

更新日期：1996-11-01 00:00:00

abstract：:A new general method for the determination of electrostatic potentials at biological surfaces is presented. The approach is based on measurement of the collision frequency of a charged nitroxide in solution with a nitroxide fixed to the surface at the point of interest. The collision frequency is determined with 14N:1...

journal_title：Biophysical journal

authors： Shin YK,Hubbell WL

更新日期：1992-06-01 00:00:00

abstract：:The rat connexin40 gap junction channel is permeable to monovalent cations including tetramethylammonium and tetraethylammonium ions. Larger tetraalkyammonium (TAA(+)) ions beginning with tetrabutylammonium (TBA(+)) reduced KCl junctional currents disproportionately. Ionic blockade by tetrapentylammonium (TPeA(+)) and...

journal_title：Biophysical journal

authors： Musa H,Gough JD,Lees WJ,Veenstra RD

更新日期：2001-12-01 00:00:00

abstract：:The solution structures of the N-terminal domains of protein S, a plasma vitamin K-dependent glycoprotein, and its homolog growth arrest specific protein 6 (Gas6) were predicted by molecular dynamics computer simulations. The initial structures were based on the x-ray crystallographic structure of the corresponding re...

journal_title：Biophysical journal

authors： Perera L,Li L,Darden T,Monroe DM,Pedersen LG

更新日期：1997-10-01 00:00:00

abstract：:A partially depolarized squid axon membrane is assumed to have a quasi-steady state negative resistance, the membrane potential is clamped at one point, and a distribution of potential along the axon is obtained from the cable equation. Nominal experimental values of -2 ohm cm(2) for the membrane and 6 ohm cm(2) for t...

journal_title：Biophysical journal

authors： COLE KS

更新日期：1961-05-01 00:00:00

abstract：:Two-photon excitation (TPE) spectra of Fura-2, -4F, -6F, -FF, and Furaptra were characterized using a tunable (750-850 nM) ultra-short pulse laser. Two-photon fluorescence of these dyes was studied in free solution and in the cytosol of isolated rabbit ventricular cardiomyocytes. The TPE spectra of the Ca(2+)-free and...

journal_title：Biophysical journal

authors： Wokosin DL,Loughrey CM,Smith GL

更新日期：2004-03-01 00:00:00

abstract：:The solutions to a general class of axon partial differential equations proposed by FitzHugh which includes the Hodgkin-Huxley equations are studied. It is shown that solutions to the partial differential equations are exactly the solutions to a related set of integral equations. An iterative procedure for constructin...

journal_title：Biophysical journal

authors： Evans J,Shenk N

更新日期：1970-11-01 00:00:00

abstract：:We describe a new method for selective laser killing of bacteria targeted with light-absorbing gold nanoparticles conjugated with specific antibodies. The multifunctional photothermal (PT) microscope/spectrometer provides a real-time assessment of this new therapeutic intervention. In this integrated system, strong la...

journal_title：Biophysical journal

authors： Zharov VP,Mercer KE,Galitovskaya EN,Smeltzer MS

更新日期：2006-01-15 00:00:00

abstract：:X-ray fiber diffraction is one of the most useful methods for examining the structural details of live biological filaments under physiological conditions. To investigate biologically active or labile materials, it is crucial to finish fiber alignment within seconds before diffraction analysis. However, the convention...

journal_title：Biophysical journal

authors： Sugiyama T,Miyashiro D,Takao D,Iwamoto H,Sugimoto Y,Wakabayashi K,Kamimura S

更新日期：2009-12-16 00:00:00

abstract：:Transient receptor potential (TRP) channels are members of a large family of ion channels located in membranes rich in cholesterol, some of whose functions are affected by the cholesterol content of the membrane. Here, cholesterol binding to TRPs is studied using a docking procedure that allows the transmembrane surfa...

journal_title：Biophysical journal

authors： Lee AG

更新日期：2019-11-19 00:00:00

abstract：:A model for the Na-K exchange pump was applied to data on Na(+)-loaded frog sartorius muscle, and was used to relate the rate of adenosine triphosphate (ATP) hydrolysis to the electrical properties of the cell membrane. Membrane hyperpolarization was considered to arise from an electrical current which was produced by...

journal_title：Biophysical journal

authors： Rapoport SI

更新日期：1971-08-01 00:00:00

abstract：:Structure factor amplitudes and phases can be computed directly from electron cryomicroscopy images. Inherent aberrations of the electromagnetic lenses and other instrumental factors affect the structure factors, however, resulting in decreased accuracy in the determined three-dimensional reconstruction. In contrast, ...

journal_title：Biophysical journal

authors： Thuman-Commike PA,Tsuruta H,Greene B,Prevelige PE Jr,King J,Chiu W

更新日期：1999-04-01 00:00:00

abstract：:In a contracting muscle, myosin cross-bridges extending from thick filaments pull the interdigitating thin (actin-containing) filaments during cyclical ATP-driven interactions toward the center of the sarcomere, the structural unit of striated muscle. Cross-bridge attachments in the sarcomere have been reported to exh...

journal_title：Biophysical journal

authors： Linari M,Piazzesi G,Pertici I,Dantzig JA,Goldman YE,Lombardi V

更新日期：2020-03-10 00:00:00

abstract：:TWIK-1 two-pore domain K(+) channels generally produce nonmeasurable or very low levels of K(+) currents in heterologous expression systems under physiologically ionic conditions. Two controversial mechanisms have been proposed to account for this behavior: TWIK-1 K(+) channels are expressed in the cell surface but si...

journal_title：Biophysical journal

authors： Ma L,Xie YP,Zhou M,Chen H

更新日期：2012-04-18 00:00:00

abstract：:We have studied the anion-dependent gating of roflamycoin ion channels using spectral analysis of noise in currents through multichannel planar lipid bilayers. We have found that in addition to low frequency current fluctuations that may be attributed to channel switching between open and closed conformations, roflamy...

journal_title：Biophysical journal

authors： Grigorjev PA,Bezrukov SM

更新日期：1994-12-01 00:00:00

abstract：:Sedimentation velocity analytical ultracentrifugation is an important tool in the characterization of macromolecules and nanoparticles in solution. The sedimentation coefficient distribution c(s) of Lamm equation solutions is based on the approximation of a single, weight-average frictional coefficient of all particle...

journal_title：Biophysical journal

authors： Brown PH,Schuck P

更新日期：2006-06-15 00:00:00

abstract：:With their longest dimension typically being less than 100 nm, molecular motors are significantly below the optical-resolution limit. Despite substantial advances in fluorescence-based imaging methodologies, labeling with beads remains critical for optical-trapping-based investigations of molecular motors. A key exper...

journal_title：Biophysical journal

authors： Li Q,King SJ,Gopinathan A,Xu J

更新日期：2016-06-21 00:00:00

abstract：:We have studied tubules formed from a polymerizable lipid in aqueous dispersion using freeze-fracture replication and transmission electron microscopy. The polymerizable diacetylenic lecithin 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine converts from liposomes to hollow cylinders, which we call tubules, o...

journal_title：Biophysical journal

authors： Yager P,Schoen PE,Davies C,Price R,Singh A

更新日期：1985-12-01 00:00:00

abstract：:The jaws of the bloodworm Glycera dibranchiata consist principally of protein and melanin scaffolds with small amounts of unmineralized copper (Cu) and mineralized atacamite (Cu(2)Cl(OH)(3)) fibers in distinct regions. Remarkably, when tested in air, the regions containing unmineralized Cu are the hardest, stiffest, a...

journal_title：Biophysical journal

authors： Moses DN,Pontin MG,Waite JH,Zok FW

更新日期：2008-04-15 00:00:00

abstract：:We present a molecular model of a chromatophore vesicle from Rhodobacter sphaeroides. These vesicles are ideal benchmark systems for molecular and systemic simulations, because they have been well studied, they are small, and they are naturally separated from their cellular environment. To set up a photosynthetic chai...

journal_title：Biophysical journal

authors： Geyer T,Helms V

更新日期：2006-08-01 00:00:00

abstract：:Light adaptation in cones was characterized by measuring the changes in temporal frequency responses to sinusoidal modulation of light around various mean levels spanning a range of four log units. We have shown previously that some aspects of cone adaptation behavior can be accounted for by a biochemical kinetic mode...

journal_title：Biophysical journal

authors： Tranchina D,Sneyd J,Cadenas ID

更新日期：1991-07-01 00:00:00

abstract：:The photocycle of the photophobic receptor sensory rhodopsin II from N. pharaonis was analyzed by varying measuring wavelengths, temperature, and pH, and by exchanging H2O with D2O. The data can be satisfactorily modeled by eight exponents over the whole range of modified parameters. The kinetic data support a model s...

journal_title：Biophysical journal

authors： Chizhov I,Schmies G,Seidel R,Sydor JR,Lüttenberg B,Engelhard M

更新日期：1998-08-01 00:00:00

abstract：:The energetics of phospholipid aggregation depend on the apparent water-accessible apolar surface area (ASAap), ordering effects of the chains, and headgroup interactions. We quantify the enthalpy and entropy of these interactions separately. For that purpose, the thermodynamics of micelle formation of lysophosphatidy...

journal_title：Biophysical journal

authors： Heerklotz H,Epand RM

更新日期：2001-01-01 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：:Viral infection begins with the binding of a virus to a specific target on the surface of the host cell, followed by viral genome delivery into the host and a continuation of the infection process. Before binding occurs, the virus must first find its receptor by a process whose details are largely unknown. We applied ...

journal_title：Biophysical journal

authors： Rothenberg E,Sepúlveda LA,Skinner SO,Zeng L,Selvin PR,Golding I

更新日期：2011-06-22 00:00:00

abstract：:In early development, Drosophila melanogaster embryos form a syncytium, i.e., multiplying nuclei are not yet separated by cell membranes, but are interconnected by cytoskeletal polymer networks consisting of actin and microtubules. Between division cycles 9 and 13, nuclei and cytoskeleton form a two-dimensional cortic...

journal_title：Biophysical journal

authors： Wessel AD,Gumalla M,Grosshans J,Schmidt CF

更新日期：2015-04-21 00:00:00

abstract：:Using the substituted-cysteine-accessibility method, we previously showed that a cysteine residue introduced to the Y512 position of CLC-0 was more rapidly modified by a negatively charged methanethiosulfonate (MTS) reagent, 2-sulfonatoethyl MTS (MTSES), than by the positively charged 2-(trimethylammonium)ethyl MTS (M...

journal_title：Biophysical journal

authors： Zhang XD,Yu WP,Chen TY

更新日期：2010-02-03 00:00:00

abstract：:The blood stage malaria parasite, the merozoite, has a small window of opportunity during which it must successfully target and invade a human erythrocyte. The process of invasion is nonetheless remarkably rapid. To date, mechanistic models of invasion have focused predominantly on the parasite actomyosin motor contri...

journal_title：Biophysical journal

authors： Dasgupta S,Auth T,Gov NS,Satchwell TJ,Hanssen E,Zuccala ES,Riglar DT,Toye AM,Betz T,Baum J,Gompper G

更新日期：2014-07-01 00:00:00