Force spectroscopy with dual-trap optical tweezers: molecular stiffness measurements and coupled fluctuations analysis.

abstract：:Molecular dynamics simulations are performed on two hydrated dipalmitoylphosphatidylcholine bilayer systems: one with pure water and one with added NaCl. Due to the rugged nature of the membrane/electrolyte interface, ion binding to the membrane surface is characterized by the loss of ion hydration. Using this structu...

journal_title：Biophysical journal

authors： Pandit SA,Bostick D,Berkowitz ML

更新日期：2003-06-01 00:00:00

abstract：:The effects of aminopyridines on ionic conductances of the squid giant axon membrane were examined using voltage clamp and internal perfusion techniques. 4-Aminopyridine (4-AP) reduced potassium currents, but had no effect upon transient sodium currents. The block of potassium channels by 4-AP was substantially less w...

journal_title：Biophysical journal

authors： Yeh JZ,Oxford GS,Wu CH,Narahashi T

更新日期：1976-01-01 00:00:00

abstract：:The early events in halorhodopsin after light excitation are studied with picosecond time resolution. Absorption and fluorescence measurements show that the electronically excited state of the incorporated retinal has a lifetime of 5 ps. Within that time a red-shifted photoproduct is formed that remains stable for at ...

journal_title：Biophysical journal

authors： Polland HJ,Franz MA,Zinth W,Kaiser W,Hegemann P,Oesterhelt D

更新日期：1985-01-01 00:00:00

abstract：:Multiple data are available on the self-assembly of mixtures of bilayer-forming amphiphiles, particularly phospholipids and micelle-forming amphiphiles, commonly denoted detergents. The structure of such mixed assemblies has been thoroughly investigated, described in phase diagrams, and theoretically rationalized in t...

journal_title：Biophysical journal

authors： Lichtenberg D,Ahyayauch H,Goñi FM

更新日期：2013-07-16 00:00:00

abstract：:Historically, predicting macroscopic blood flow characteristics such as viscosity has been an empirical process due to the difficulty in rigorously including the particulate nature of blood in a mathematical representation of blood rheology. Using a two-dimensional lattice Boltzmann approach, we have simulated the flo...

journal_title：Biophysical journal

authors： Sun C,Munn LL

更新日期：2005-03-01 00:00:00

abstract：:Lateral organization of cholesterol in dioleoyl-phosphatidylcholine (DOPC) lipid bilayers at high cholesterol concentration (>45 mol%) was investigated using steady-state fluorescence anisotropy and fluorescent resonance energy transfer techniques. The recently devised Low Temperature Trap method was used to prepare c...

journal_title：Biophysical journal

authors： Parker A,Miles K,Cheng KH,Huang J

更新日期：2004-03-01 00:00:00

abstract：:A theoretical framework is developed to study the dynamics of protein folding. The key insight is that the search for the native protein conformation is influenced by the rate r at which external parameters, such as temperature, chemical denaturant, or pH, are adjusted to induce folding. A theory based on this insight...

journal_title：Biophysical journal

authors： Lois G,Blawzdziewicz J,O'Hern CS

更新日期：2008-09-15 00:00:00

abstract：:Microbial capsules are important for virulence, but their architecture and physical properties are poorly understood. The human pathogenic fungus Cryptococcus neoformans has a large polysaccharide capsule that is necessary for virulence and is the target of protective antibody responses. To study the C. neoformans cap...

journal_title：Biophysical journal

authors： Frases S,Pontes B,Nimrichter L,Rodrigues ML,Viana NB,Casadevall A

更新日期：2009-08-19 00:00:00

abstract：:A recent theory for the long time dynamics of flexible chain molecules is applied for the first time to a peptide of biological importance, the neurotransmitter met-enkephalin. The dynamics of met-enkephalin is considerably more complicated than that of the previously studied glycine oligomers; met-enkephalin contains...

journal_title：Biophysical journal

authors： Kostov KS,Freed KF

更新日期：1999-01-01 00:00:00

abstract：:The pores of ion channel proteins are often modeled as static structures. In this view, selectivity reflects rigidly constrained backbone orientations. Such a picture is at variance with the generalization that biological proteins are flexible, capable of major internal motions on biologically relevant time scales. We...

journal_title：Biophysical journal

authors： Bénitah JP,Ranjan R,Yamagishi T,Janecki M,Tomaselli GF,Marban E

更新日期：1997-08-01 00:00:00

abstract：:The kinetics of methyl-, ethyl-, iso-propyl-, and ter-butyl-isocyanide binding to Aplysia limacina myoglobin (distal His----Lys) and the isolated beta chains from hemoglobin Zurich (distal His----Arg) have been investigated by flash photolysis at various temperatures above 0 degrees C. Sperm whale (Physter catodon) my...

journal_title：Biophysical journal

authors： Di Iorio EE,Winterhalter KH,Giacometti GM

更新日期：1987-03-01 00:00:00

abstract：:Disruption of the integrity of the plasma membrane by amyloidogenic proteins is linked to the pathogenesis of a number of common age-related diseases. Although accumulating evidence suggests that adverse environmental stressors such as unbalanced levels of metal ions may trigger amyloid-mediated membrane damage, many ...

journal_title：Biophysical journal

authors： Sciacca MF,Milardi D,Messina GM,Marletta G,Brender JR,Ramamoorthy A,La Rosa C

更新日期：2013-01-08 00:00:00

abstract：:A number of properties of certain living embryonic tissues can be explained by considering them as liquids. Tissue fragments left in a shaker bath round up to form spherical aggregates, as do liquid drops. When cells comprising two distinct embryonic tissues are mixed, typically a nucleation-like process takes place, ...

journal_title：Biophysical journal

authors： Forgacs G,Foty RA,Shafrir Y,Steinberg MS

更新日期：1998-05-01 00:00:00

abstract：:The current-voltage (I-V) relation of the background current, IK1, was studied in isolated canine cardiac Purkinje myocytes using the whole-cell, patch-clamp technique. Since Ba2+ and Cs+ block IK1, these cations were used to separate the I-V relation of IK1 from that of the whole cell. The I-V relation of IK1 was mea...

journal_title：Biophysical journal

authors： Shah AK,Cohen IS,Datyner NB

更新日期：1987-10-01 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：:hbAP0 is a model membrane protein designed to possess an anesthetic-binding cavity in its hydrophilic domain and a cation channel in its hydrophobic domain. Grazing incidence x-ray diffraction shows that hbAP0 forms four-helix bundles that are vectorially oriented within Langmuir monolayers at the air-water interface....

journal_title：Biophysical journal

authors： Churbanova IY,Tronin A,Strzalka J,Gog T,Kuzmenko I,Johansson JS,Blasie JK

更新日期：2006-05-01 00:00:00

abstract：:Ion channels enable diffusion of ions down physiological electrochemical gradients. Modulation of ion permeation is crucial for the physiological functioning of cells, and misregulation of ion channels is linked to a myriad of channelopathies. The ion permeation mechanism in the transient receptor potential (TRP) ion ...

journal_title：Biophysical journal

authors： Jorgensen C,Furini S,Domene C

更新日期：2016-09-20 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：:The depth of insertion of an antimicrobial peptide, protegrin-1 (PG-1), in lipid bilayers is investigated using solid-state NMR. Paramagnetic Mn(2+) ions bind to the surface of lipid bilayers and induce distance-dependent dipolar relaxation of nuclear spins. By comparing the signal dephasing of the peptide with that o...

journal_title：Biophysical journal

authors： Buffy JJ,Hong T,Yamaguchi S,Waring AJ,Lehrer RI,Hong M

更新日期：2003-10-01 00:00:00

abstract：:Low-power continuous-wave laser radiation is used to form a very stable microbubble at the end of a specially etched and metalized optical fiber probe. We demonstrate that the microbubble, which is firmly attached to the fiber probe, can be used to benignly trap and manipulate living swine sperm cells as well as human...

journal_title：Biophysical journal

authors： Diop M,Taylor R

更新日期：2006-05-15 00:00:00

abstract：:Understanding exposure thresholds for the response of biological systems to extremely low frequency (ELF) electric and magnetic fields is a fundamental problem of long-standing interest. We consider a two-state model for voltage-gated channels in the membrane of an isolated elongated cell (Lcell = 1 mm; rcell = 25 mic...

journal_title：Biophysical journal

authors： Weaver JC,Vaughan TE,Adair RK,Astumian RD

更新日期：1998-11-01 00:00:00

abstract：:A study on clonal growth in Chinese hamster ovary (CHO) cells was conducted after exposure to optical trapping wavelengths using Nd:YAG (1064 nm) and tunable titanium-sapphire (700-990 nm) laser microbeam optical traps. The nuclei of cells were exposed to optical trapping forces at various wavelengths, power densities...

journal_title：Biophysical journal

authors： Liang H,Vu KT,Krishnan P,Trang TC,Shin D,Kimel S,Berns MW

更新日期：1996-03-01 00:00:00

abstract：:Impact loading of articular cartilage causes extensive chondrocyte death. Cell membranes have a limited elastic range of 3-4% strain but are protected from direct stretch during physiological loading by their membrane reservoir, an intricate pattern of membrane folds. Using a finite-element model, we suggested previou...

journal_title：Biophysical journal

authors： Moo EK,Amrein M,Epstein M,Duvall M,Abu Osman NA,Pingguan-Murphy B,Herzog W

更新日期：2013-10-01 00:00:00

abstract：:Polarized photolysis experiments have been performed on the carbon monoxide complex of myoglobin to assess the effects of photoselection on the kinetics of ligand rebinding and to investigate the reorientational dynamics of the heme plane. The results are analyzed in terms of the optical theory developed in the preced...

journal_title：Biophysical journal

authors： Ansari A,Jones CM,Henry ER,Hofrichter J,Eaton WA

更新日期：1993-03-01 00:00:00

abstract：:Histograms of single-molecule Förster resonance energy transfer (FRET) efficiency are often used to study the structures of biomolecules and relate these structures to function. Methods like probability distribution analysis analyze FRET histograms to detect heterogeneities in molecular structure, but they cannot dete...

journal_title：Biophysical journal

authors： Torella JP,Holden SJ,Santoso Y,Hohlbein J,Kapanidis AN

更新日期：2011-03-16 00:00:00

abstract：:The spatiotemporal organization and dynamics of the plasma membrane and its constituents are central to cellular function. Fluorescence-based single-particle tracking has emerged as a powerful approach for studying the single molecule behavior of plasma-membrane-associated events because of its excellent background su...

journal_title：Biophysical journal

authors： de Wit G,Albrecht D,Ewers H,Kukura P

更新日期：2018-06-19 00:00:00

abstract：:The outer membrane porin OmpF from Escherichia coli has been reconstituted into lipid bilayers of defined composition, and fluorescence spectroscopy is used to characterize its interaction with the surrounding lipid. OmpF is a trimer within the membrane. It contains two Trp residues per monomer, Trp(214) at the lipid-...

journal_title：Biophysical journal

authors： O'Keeffe AH,East JM,Lee AG

更新日期：2000-10-01 00:00:00

abstract：:A method for generating angular forces around sigma-bonded transition metal ions is generalized to treat pi-bonded configurations. The theoretical approach is based on an analysis of ligand-field and small-cluster Hamiltonians based on the moments of the electron state distribution. The functional forms that are obtai...

journal_title：Biophysical journal

authors： Carlsson AE,Zapata S

更新日期：2001-07-01 00:00:00

abstract：:We showed recently that the high-salt transition of poly[d(G-C)]. poly[d(G-C)] between B-DNA and Z-DNA (at [NaCl] = 2.25 M or [MgCl(2)] = 0.7 M) can be ascribed to the lesser electrostatic free energy of the B form, due to better immersion of the phosphates in the solution. This property was incorporated in cylindrica...

journal_title：Biophysical journal

authors： Guéron M,Demaret J,Filoche M

更新日期：2000-02-01 00:00:00

abstract：:Optical mapping with voltage-sensitive dyes provides a high-resolution technique to observe cardiac electrodynamic behavior. Although most studies assume that the fluorescent signal is emitted from the surface layer of cells, the effects of signal attenuation with depth on signal interpretation are still unclear. This...

journal_title：Biophysical journal

authors： Bray MA,Wikswo JP

更新日期：2003-12-01 00:00:00