Novel chelate-induced magnetic alignment of biological membranes.

abstract：:Pyranine (8-hydroxy pyrene-1,3,6-trisulfonate) is a commonly used photoacid that discharges a proton when excited to its first electronic singlet state. Follow-up of its dissociation kinetics reveals the physicochemical properties of its most immediate environment. At vanishing ionic strength the dye adsorbs to the Es...

journal_title：Biophysical journal

authors： Nachliel E,Pollak N,Huppert D,Gutman M

更新日期：2001-03-01 00:00:00

abstract：:The effects of Mg++ on the spatial organization of nuclei from rat hepatocytes are analyzed in the range 0-60 mM, in the presence of suitable concentrations of KCl to reproduce physiological conditions. It is shown that the scatter-signal distribution measured by means of a flow microfluorimeter is greatly affected by...

journal_title：Biophysical journal

authors： Grattarola M,Carlo P,Giannetti G,Finollo R,Viviani R,Chiabrera A

更新日期：1985-04-01 00:00:00

abstract：:Omega-3 polyunsaturated fatty acids (n-3 PUFA), enriched in fish oils, are increasingly recognized to have potential benefits for treating many human afflictions. Despite the importance of PUFA, their molecular mechanism of action remains unclear. One emerging hypothesis is that phospholipids containing n-3 PUFA acyl ...

journal_title：Biophysical journal

authors： Williams JA,Batten SE,Harris M,Rockett BD,Shaikh SR,Stillwell W,Wassall SR

更新日期：2012-07-18 00:00:00

abstract：:Monolayers of a functional pulmonary surfactant (PS) can reach very low surface tensions well below their equilibrium value. The mechanism by which PS monolayers reach such low surface tensions and maintain film stability remains unknown. As shown previously by fluorescence microscopy, phospholipid phase transition an...

journal_title：Biophysical journal

authors： Zuo YY,Keating E,Zhao L,Tadayyon SM,Veldhuizen RA,Petersen NO,Possmayer F

更新日期：2008-05-01 00:00:00

abstract：:We report detection and quantification of ultraviolet (UV) damage in DNA at a single molecule level by atomic force microscopy (AFM). By combining the supercoiled plasmid relaxation assay with AFM imaging, we find that high doses of medium wave ultraviolet (UVB) and short wave ultraviolet (UVC) light not only produce ...

journal_title：Biophysical journal

authors： Jiang Y,Ke C,Mieczkowski PA,Marszalek PE

更新日期：2007-09-01 00:00:00

abstract：:Molecular dynamics (MD) simulations of 5 ns on protein-DNA complexes of catabolite-activator protein (CAP), lambda-repressor, and their corresponding uncomplexed protein and DNA, are reported. These cases represent two extremes of DNA bending, with CAP DNA bent severely and the lambda-operator nearly straight when com...

journal_title：Biophysical journal

authors： Dixit SB,Andrews DQ,Beveridge DL

更新日期：2005-05-01 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：:Verapamil and amlodipine are calcium ion influx inhibitors of wide clinical use. They are partially charged at neutral pH and exhibit amphiphilic properties. The noncharged species can easily cross the lipid membrane. We have measured with solid-state NMR the structural changes induced by verapamil upon incorporation ...

journal_title：Biophysical journal

authors： Meier M,Blatter XL,Seelig A,Seelig J

更新日期：2006-10-15 00:00:00

abstract：:An approach is described using fluorescence resonance energy transfer (FRET) to detect inhomogeneity in lipid organization, on distance scales of the order of tens of nanometers or greater, in lipid bilayers. This approach compares the efficiency of energy transfer between two matched fluorescent lipid donors, differi...

journal_title：Biophysical journal

authors： Silvius JR

更新日期：2003-08-01 00:00:00

abstract：:The role of the extracellular Glu side chains of bacteriorhodopsin in the proton transport mechanism has been studied using the single mutants E9Q, E74Q, E194Q, and E204Q; the triple mutant E9Q/E194Q/E204Q; and the quadruple mutant E9Q/E74Q/E194Q/E204Q. Steady-state difference and deconvoluted Fourier transform infrar...

journal_title：Biophysical journal

authors： Lazarova T,Sanz C,Querol E,Padrós E

更新日期：2000-04-01 00:00:00

abstract：:Computational methods that predict three-dimensional structures from amino acid sequences have become increasingly accurate and have provided insights into structure-function relationships for proteins in the absence of structural data. However, the accuracy of computational structural models requires experimental app...

journal_title：Biophysical journal

authors： Tateyama M,Liu H,Yang AS,Cormier JW,Kass RS

更新日期：2004-03-01 00:00:00

abstract：:Guanidinium and acetamidinium, when added to the bathing solution in concentrations of approximately 0.1M, cause brief blocks in the single channel potassium currents from channels formed in planar lipid bilayers by gramicidin A. Single channel lifetimes are not affected indicating that the channel structure is not mo...

journal_title：Biophysical journal

authors： Hemsley G,Busath D

更新日期：1991-04-01 00:00:00

abstract：:The dynamics of protein distribution in endocytic membranes are relevant for many cellular processes, such as protein sorting, organelle and membrane microdomain biogenesis, protein-protein interactions, receptor function, and signal transduction. We have developed an assay based on Fluorescence Resonance Energy Micro...

journal_title：Biophysical journal

authors： Wallrabe H,Elangovan M,Burchard A,Periasamy A,Barroso M

更新日期：2003-07-01 00:00:00

abstract：:The patch-clamp technique of Mueller (1975, Ann. N.Y. Acad. Sci., 274:247-264) and Neher and Sakmann (1976, Nature (Lond.), 260:799-802) was modified to be suitable for single-channel measurements in lipid bilayers at potentials up to 500 mV. This method was used to study gramicidin A single-channel current-voltage ch...

journal_title：Biophysical journal

authors： Andersen OS

更新日期：1983-02-01 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：:Using a recently developed in vitro motility assay, we have demonstrated that local anesthetics directly inhibit myosin-based movement of single actin filaments in a reversible dose-dependent manner. This is the first reported account of the actions of local anesthetics on purified proteins at the molecular level. In ...

journal_title：Biophysical journal

authors： Tsuda Y,Mashimo T,Yoshiya I,Kaseda K,Harada Y,Yanagida T

更新日期：1996-11-01 00:00:00

abstract：:Flow dialysis has found widespread use in determining the dissociation constant (KD) of a protein-ligand interaction or the amount of available binding sites (E0). This method has the potency to measure both these parameters in a single experiment and in this article a method to measure simultaneously the KD and E0 is...

journal_title：Biophysical journal

authors： Veldhuis G,Vos EP,Broos J,Poolman B,Scheek RM

更新日期：2004-04-01 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：:The interaction between actin and myosin in the filament array of glycerinated muscle fibers has been monitored using paramagnetic probes and mechanical measurements. Both fiber stiffness and the spectra of probes bound to a reactive sulfydral on the myosin head were measured as the actomyosin bond was weakened by add...

journal_title：Biophysical journal

authors： Pate E,Cooke R

更新日期：1988-04-01 00:00:00

abstract：:Membranes made of dimyristoylphosphatidylcholine and cholesterol, one of the simplest paradigms for the study of liquid ordered-disordered phase separation, were investigated using a pulse-EPR spin-labeling method in which bimolecular collision of molecular oxygen with the nitroxide spin label is measured. This method...

journal_title：Biophysical journal

authors： Subczynski WK,Wisniewska A,Hyde JS,Kusumi A

更新日期：2007-03-01 00:00:00

abstract：:The energy transfer and charge separation kinetics of a photosystem I (PS I) core particle of an antenna size of 100 chlorophyll/P700 has been studied by combined fluorescence and transient absorption kinetics with picosecond resolution. This is the first combined picosecond study of transient absorption and fluoresce...

journal_title：Biophysical journal

authors： Holzwarth AR,Schatz G,Brock H,Bittersmann E

更新日期：1993-06-01 00:00:00

abstract：:Based on experimental evidence for 2D array formation of bacteriorhodopsin, we propose a general model for lipid-mediated 2D array formation of membrane proteins in lipid bilayers. The model includes two different lipid species, "annular" lipids and "neutral" lipids, and one protein species. The central assumption of ...

journal_title：Biophysical journal

authors： Sabra MC,Uitdehaag JC,Watts A

更新日期：1998-09-01 00:00:00

abstract：:Molecular dynamics simulations of RNA-protein complex between Escherichia coli loop E/helix IV (LE/HeIV) rRNA and L25 protein reveal a qualitative agreement between the experimental and simulated structures. The major groove of LE is a prominent rRNA cation-binding site. Divalent cations rigidify the LE major groove g...

journal_title：Biophysical journal

authors： Réblová K,Spacková N,Koca J,Leontis NB,Sponer J

更新日期：2004-11-01 00:00:00

abstract：:The oligomerization of the plasma membrane calcium pump (PMCA) in phospholipid/detergent micelles was evaluated using a combined spectroscopic and kinetic approach and related to the enzyme stability. Energy transfer between fluorescein-5'-isothiocyanate and eosin-5'-isothiocyanate attached to different PMCA molecules...

journal_title：Biophysical journal

authors： Levi V,Rossi JP,Castello PR,González Flecha FL

更新日期：2002-01-01 00:00:00

abstract：:We report the first time-resolved study of the two-dimensional x-ray diffraction pattern during active contraction in insect flight muscle (IFM). Activation of demembranated Lethocerus IFM was triggered by 1.5-2.5% step stretches (risetime 10 ms; held for 1.5 s) giving delayed active tension that peaked at 100-200 ms....

journal_title：Biophysical journal

authors： Tregear RT,Edwards RJ,Irving TC,Poole KJ,Reedy MC,Schmitz H,Towns-Andrews E,Reedy MK

更新日期：1998-03-01 00:00:00

abstract：:Intracellular reactions are carried out in a crowded medium where the macromolecules occupy ∼40% of the total volume. This decrease in the available volume affects the activity of the reactants. Scaled particle theory is used for the estimation of the activity coefficients of the metabolites, and thereby for the asses...

journal_title：Biophysical journal

authors： Angeles-Martinez L,Theodoropoulos C

更新日期：2015-12-01 00:00:00

abstract：:An interactive program is described for calculating the second virial coefficient contribution to the thermodynamic nonideality of solutions of rigid macromolecules based on their triaxial dimensions. The FORTRAN-77 program, available in precompiled form for the PC, is based on theory for the covolume of triaxial elli...

journal_title：Biophysical journal

authors： Harding SE,Horton JC,Jones S,Thornton JM,Winzor DJ

更新日期：1999-05-01 00:00:00

abstract：:A major challenge in synthetic gene delivery is to quantitatively predict the optimal design of polymer-based gene carriers (polyplexes). Here, we report a consistent, integrated, and fundamentally grounded computational methodology to address this challenge. This is achieved by accurately representing the spatio-temp...

journal_title：Biophysical journal

authors： Dinh AT,Pangarkar C,Theofanous T,Mitragotri S

更新日期：2007-02-01 00:00:00

abstract：:In this review, we focus on the early events in the process of fibroblast spreading on fibronectin matrices of different rigidities. We present a focused position piece that illustrates the many different tests that a cell makes of its environment before it establishes mature matrix adhesions. When a fibroblast is pla...

journal_title：Biophysical journal

authors： Wolfenson H,Iskratsch T,Sheetz MP

更新日期：2014-12-02 00:00:00

abstract：:Human apolipoprotein E (apoE) is a 299-amino-acid protein with a molecular weight of 34 kDa. The difference between the apoE3 and apoE4 isoforms is a single residue substitution involving a Cys-Arg replacement at residue 112. ApoE4 is positively associated with atherosclerosis and late-onset and sporadic Alzheimer's d...

journal_title：Biophysical journal

authors： Chou CY,Lin YL,Huang YC,Sheu SY,Lin TH,Tsay HJ,Chang GG,Shiao MS

更新日期：2005-01-01 00:00:00