Time-resolved x-ray diffraction and calorimetric studies at low scan rates: II. On the fine structure of the phase transitions in hydrated dipalmitoylphosphatidylethanolamine.

abstract：:Can individual cells, including live cells, be imaged using hard x rays? Common wisdom until now required sophisticated staining techniques for this task. We show instead that individual cells and cell details can be detected in culture solution and tissues with no staining and no other contrast-enhancing preparation....

journal_title：Biophysical journal

authors： Hwu Y,Tsai WL,Chang HM,Yeh HI,Hsu PC,Yang YC,Su YT,Tsai HL,Chow GM,Ho PC,Li SC,Moser HO,Yang P,Seol SK,Kim CC,Je JH,Stefanekova E,Groso A,Margaritondo G

更新日期：2004-12-01 00:00:00

abstract：:Chromatin is partitioned on multiple length scales into subcompartments that differ from each other with respect to their molecular composition and biological function. It is a key question how these compartments can form even though diffusion constantly mixes the nuclear interior and rapidly balances concentration gr...

journal_title：Biophysical journal

authors： Erdel F,Rippe K

更新日期：2018-05-22 00:00:00

abstract：:Force spectroscopy is commonly used to measure the kinetics of processes occurring in single biological molecules. These measurements involve attaching the molecule of interest to micron-sized or larger force probes via compliant linkers. Recent theoretical work has described how the properties of the probes and linke...

journal_title：Biophysical journal

authors： Neupane K,Woodside MT

更新日期：2016-07-26 00:00:00

abstract：:We present the results of a detailed molecular dynamics study of the closed form of the P2X4 receptor. The fluctuations observed in the simulations were compared with the changes that occur in the transition from the closed to the open structure. To get further insight on the opening mechanism, the actual displacement...

journal_title：Biophysical journal

authors： Pierdominici-Sottile G,Moffatt L,Palma J

更新日期：2016-12-20 00:00:00

abstract：:The general theory (Levitt, D. G. 1990. Biophys. J. 59:271-277) is applied to a model channel that resembles the acetylcholine receptor channel (ACH). The model incorporates the known features of the ACH geometry and fixed charge locations. The channel has a wide mouth facing the outer solution, tapering to a narrow r...

journal_title：Biophysical journal

authors： Levitt DG

更新日期：1991-02-01 00:00:00

abstract：:An alternative theoretical approach to enzyme kinetics that is particularly applicable to single-molecule enzymology is presented. The theory, originated by Van Slyke and Cullen in 1914, develops enzyme kinetics from a "time perspective" rather than the traditional "rate perspective" and emphasizes the nonequilibrium ...

journal_title：Biophysical journal

authors： Qian H

更新日期：2008-07-01 00:00:00

abstract：:Actin dynamics is important in determining cell shape, tension, and migration. Methods such as fluorescent speckle microscopy and spatial temporal image correlation spectroscopy have been used to capture high-resolution actin turnover dynamics within cells in two dimensions. However, these methods are not directly app...

journal_title：Biophysical journal

authors： Chiu CL,Digman MA,Gratton E

更新日期：2013-10-15 00:00:00

abstract：:The vibrational energy relaxation of a selected vibrational mode in cytochrome c--a C-D stretch in the terminal methyl group of Met80--has been studied using equilibrium molecular dynamics simulation and normal mode analysis methods. As demonstrated in the pioneering work of Romesberg and co-workers, isotopic labeling...

journal_title：Biophysical journal

authors： Bu L,Straub JE

更新日期：2003-09-01 00:00:00

abstract：:We apply fluorescence lifetime imaging to the membrane phase-sensing dye di-4-ANEPPDHQ in model membranes and live cells. We show that the 1700 ps lifetime shift between liquid-disordered and liquid-ordered phases offers greater contrast than the 60 nm spectral shift previously reported. Detection of cholesterol-rich ...

journal_title：Biophysical journal

authors： Owen DM,Lanigan PM,Dunsby C,Munro I,Grant D,Neil MA,French PM,Magee AI

更新日期：2006-06-01 00:00:00

abstract：:The effects of different cations on the hydrodynamic radius (RH) of a 48-bp synthetic DNA are measured by time-resolved fluorescence polarization anisotropy of intercalated ethidium. Relative statistical errors in RH are only approximately 1%. With increasing cation concentration, Na+ causes a small decrease in RH, Cs...

journal_title：Biophysical journal

authors： Fujimoto BS,Miller JM,Ribeiro NS,Schurr JM

更新日期：1994-07-01 00:00:00

abstract：:Intracellular Ca2+ was determined with the fura-2 technique during electrically induced contractions in the rabbit rectococcygeus smooth muscle at 22 degreesC. The muscles were electrically activated to give short, reproducible contractions. Intracellular [Ca2+] increased during activation; the increase in [Ca2+] prec...

journal_title：Biophysical journal

authors： Arner A,Malmqvist U,Rigler R

更新日期：1998-10-01 00:00:00

abstract：:Frog skeletal muscle fibers, mechanically skinned under water-saturated silicone oil, swell upon transfer to aqueous relaxing medium (60 mM KCl; 3 mM MgCl(2); 3 mM ATP; 4 mM EGTA; 20 mM Tris maleate; pH = 7.0; ionic strength 0.15 M). Their cross-sectional areas, estimated with an elliptical approximation, increase 2.3...

journal_title：Biophysical journal

authors： Godt RE,Maughan DW

更新日期：1977-08-01 00:00:00

abstract：:To elucidate the mechanisms of cooperativity of cytochrome P450eryF an SH-reactive fluorescent probe was introduced close to the substrate-binding site. Cys-154, the only accessible cysteine, was eliminated by site-directed mutagenesis, and a novel cysteine was substituted for Ser-93 in the B'/C loop. S93C, C154A, C15...

journal_title：Biophysical journal

authors： Davydov DR,Botchkareva AE,Davydova NE,Halpert JR

更新日期：2005-07-01 00:00:00

abstract：:The conduction properties of ClC-0 and ClC-1 chloride channels are examined using electrostatic calculations and three-dimensional Brownian dynamics simulations. We create an open-state configuration of the prokaryotic ClC Cl(-) channel using its known crystallographic structure as a basis. Two residues that are occlu...

journal_title：Biophysical journal

authors： Corry B,O'Mara M,Chung SH

更新日期：2004-02-01 00:00:00

abstract：:A new Fourier series representation of supercoiled DNA is employed in Langevin dynamics simulations to study large-scale configurational motions of intermediate-length chains. The polymer is modeled as an ideal elastic rod subject to long-range van der Waals' interactions. The van der Waals' term prevents the self-con...

journal_title：Biophysical journal

authors： Liu G,Schlick T,Olson AJ,Olson WK

更新日期：1997-10-01 00:00:00

abstract：:It is now rare to find biological, or genetic investigations that do not rely on the tools, data, and thinking drawn from the genomic sciences. Much of this revolution is powered by contemporary sequencing approaches that readily deliver large, genome-wide data sets that not only provide genetic insights but also uniq...

journal_title：Biophysical journal

authors： Schwartz DC

更新日期：2019-12-03 00:00:00

abstract：:It has been a long belief that release of substances from the cell to the extracellular milieu by exocytosis is completed by diffusion of the substances from secretory vesicles through the fusion pore. Involvement of any mechanical force that may be superposed on the diffusion to enhance the releasing process has not ...

journal_title：Biophysical journal

authors： Tsuboi T,Kikuta T,Sakurai T,Terakawa S

更新日期：2002-07-01 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：:The canonical mechanism of gramicidin (gA) channel formation is transmembrane dimerization of nonconducting subunits that reside in opposite bilayer leaflets. The channels do not open and close; they appear and disappear due to subunit association and dissociation. Many different types of experiments support this mono...

journal_title：Biophysical journal

authors： Lum K,Ingólfsson HI,Koeppe RE 2nd,Andersen OS

更新日期：2017-10-17 00:00:00

abstract：:We present a qualitative computer graphics approach to the characterization of forces important to the assembly of beta domains that should have general utility for examining protein interactions and assembly. In our approach, the nature of the molecular surface buried by the domain contacts, the specificity of the re...

journal_title：Biophysical journal

authors： Getzoff ED,Tainer JA,Olson AJ

更新日期：1986-01-01 00:00:00

abstract：:The information theory measure of transfer entropy is used to extract the causality of correlated motions from molecular dynamics simulations. For each pair of correlated residues, the method quantifies which residue drives the correlated motions, and which residue responds. The measure reveals how correlated motions ...

journal_title：Biophysical journal

authors： Kamberaj H,van der Vaart A

更新日期：2009-09-16 00:00:00

abstract：:Mutant Ras proteins are important drivers of human cancers, yet no approved drugs act directly on this difficult target. Over the last decade, the idea has emerged that oncogenic signaling can be diminished by molecules that drive Ras into orientations in which effector-binding interfaces are occluded by the cell memb...

journal_title：Biophysical journal

authors： Neale C,García AE

更新日期：2020-03-10 00:00:00

abstract：:By considering how polymer structures are distributed in conformation space, we show that it is possible to quantify the difficulty of structural prediction and to provide a measure of progress for prediction calculations. The critical issue is the probability that a conformation is found within a specified distance o...

journal_title：Biophysical journal

authors： Sullivan DC,Kuntz ID

更新日期：2004-07-01 00:00:00

abstract：:The process of clathrin self-assembly into closed shells with the Fullerene structure is investigated. It is argued that the shell size distribution is governed by the kinetics of assembly and depends on the rate of growth controlled by the free clathrin concentration. The particularly abundant small structures--the "...

journal_title：Biophysical journal

authors： Shraiman BI

更新日期：1997-02-01 00:00:00

abstract：:We present a new method for analyzing the dynamics of conformational fluctuations of individual flexible polymer molecules. In single-particle tracking (SPT), one end of the polymer molecule is tethered to an immobile substratum. A microsphere attached to the other end serves as an optical marker. The conformational f...

journal_title：Biophysical journal

authors： Qian H,Elson EL

更新日期：1999-03-01 00:00:00

abstract：:We elucidate the physics of protein dynamical transition via 10-100-ns molecular dynamics simulations at temperatures spanning 160-300 K. By tracking the energy fluctuations, we show that the protein dynamical transition is marked by a crossover from nonstationary to stationary processes that underlie the dynamics of ...

journal_title：Biophysical journal

authors： Okan OB,Atilgan AR,Atilgan C

更新日期：2009-10-07 00:00:00

abstract：:A new microscopic technique is demonstrated that combines attributes from both near-field scanning optical microscopy (NSOM) and fluorescence resonance energy transfer (FRET). The method relies on attaching the acceptor dye of a FRET pair to the end of a near-field fiber optic probe. Light exiting the NSOM probe, whic...

journal_title：Biophysical journal

authors： Vickery SA,Dunn RC

更新日期：1999-04-01 00:00:00

abstract：:The effects of lipid chain packing and permeant size and shape on permeability across lipid bilayers have been investigated in gel and liquid crystalline dipalmitoylphosphatidylcholine (DPPC) bilayers by a combined NMR line-broadening/dynamic light scattering method using seven short-chain monocarboxylic acids (formic...

journal_title：Biophysical journal

authors： Xiang TX,Anderson BD

更新日期：1998-12-01 00:00:00

abstract：:Gap junction conductance (Gj) and channel gating sensitivity to voltage, Ca2+, H+, and heptanol were studied by double whole-cell clamp in Novikoff hepatoma cell pairs. Channel gating was observed at transjunctional voltages (Vj) > +/- 50 mV. The cells readily uncoupled with 1 mM 1-heptanol. With heptanol, single (gap...

journal_title：Biophysical journal

authors： Lazrak A,Peracchia C

更新日期：1993-11-01 00:00:00

abstract：:Using CD spectroscopy, guanine tetraplex formation was studied with short DNA fragments in which cytosine residues were systematically added to runs of guanine either at the 5' or 3' ends. Potassium cations induced the G-tetraplex more easily with fragments having the guanine run at the 5' end, which is just an opposi...

journal_title：Biophysical journal

authors： Penázová H,Vorlicková M

更新日期：1997-10-01 00:00:00