Behavior of supercoiled DNA.

Abstract:

:We study DNA supercoiling in a quantitative fashion by micromanipulating single linear DNA molecules with a magnetic field gradient. By anchoring one end of the DNA to multiple sites on a magnetic bead and the other end to multiple sites on a glass surface, we were able to exert torsional control on the DNA. A rotating magnetic field was used to induce rotation of the magnetic bead, and reversibly over- and underwind the molecule. The magnetic field was also used to increase or decrease the stretching force exerted by the magnetic bead on the DNA. The molecule's degree of supercoiling could therefore be quantitatively controlled and monitored, and tethered-particle motion analysis allowed us to measure the stretching force acting on the DNA. Experimental results indicate that this is a very powerful technique for measuring forces at the picoscale. We studied the effect of stretching forces ranging from 0.01 pN to 100 pN on supercoiled DNA (-0.1 < sigma < 0.2) in a variety of ionic conditions. Other effects, such as stretching-relaxing hysteresis and the braiding of two DNA molecules, are discussed.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Strick TR,Allemand JF,Bensimon D,Croquette V

doi

10.1016/S0006-3495(98)77908-1

subject

Has Abstract

pub_date

1998-04-01 00:00:00

pages

2016-28

issue

4

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(98)77908-1

journal_volume

74

pub_type

杂志文章
  • The stochastic dynamics of filopodial growth.

    abstract::A filopodium is a cytoplasmic projection, exquisitely built and regulated, which extends from the leading edge of the migrating cell, exploring the cell's neighborhood. Commonly, filopodia grow and retract after their initiation, exhibiting rich dynamical behaviors. We model the growth of a filopodium based on a stoch...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.107.123778

    authors: Lan Y,Papoian GA

    更新日期:2008-05-15 00:00:00

  • Formation of "solvent-free" black lipid bilayer membranes from glyceryl monooleate dispersed in squalene.

    abstract::A simple technique for forming "black" lipid bilayer membranes containing negligible amounts of alkyl solvent is described. The membranes are formed by the method of Mueller et al (Circulation. 1962. 26:1167.) from glyceryl monooleate (GMO) dispersed in squalene. The squalene forms an annulus to satisfy the boundary c...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(78)85453-8

    authors: White SH

    更新日期:1978-09-01 00:00:00

  • Novel chelate-induced magnetic alignment of biological membranes.

    abstract::A phospholipid chelate complexed with ytterbium (DMPE-DTPA:Yb3+) is shown to be readily incorporated into a model membrane system, which may then be aligned in a magnetic field such that the average bilayer normal lies along the field. This so-called positively ordered smectic phase, whose lipids consist of less than ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(98)77659-3

    authors: Prosser RS,Volkov VB,Shiyanovskaya IV

    更新日期:1998-11-01 00:00:00

  • Detachment of agglutinin-bonded red blood cells. III. Mechanical analysis for large contact areas.

    abstract::An experimental method and analysis are introduced which provide direct quantitation of the strength of adhesive contact for large agglutinin-bonded regions between macroscopically smooth membrane capsules (e.g., red blood cells). The approach yields intrinsic properties for separation of adherent regions independent ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(91)82298-6

    authors: Berk D,Evans E

    更新日期:1991-04-01 00:00:00

  • Inner sarcolemmal leaflet Ca(2+) binding: its role in cardiac Na/Ca exchange.

    abstract::A recently completed model of Ca concentration and movements in the cardiac cell diadic cleft space predicts that removal or neutralization of inner sarcolemmal (SL) leaflet anionic Ca-binding sites at the sarcolemmal border of this space will greatly diminish Na/Ca exchange-mediated Ca efflux. The present study tests...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(96)79792-8

    authors: Wang SY,Peskoff A,Langer GA

    更新日期:1996-05-01 00:00:00

  • Molecular dynamics and principal components analysis of human telomeric quadruplex multimers.

    abstract::Guanine-rich DNA repeat sequences located at the terminal ends of chromosomal DNA can fold in a sequence-dependent manner into G-quadruplex structures, notably the terminal 150-200 nucleotides at the 3' end, which occur as a single-stranded DNA overhang. The crystal structures of quadruplexes with two and four human t...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.107.120501

    authors: Haider S,Parkinson GN,Neidle S

    更新日期:2008-07-01 00:00:00

  • Induction of morphological changes in model lipid membranes and the mechanism of membrane disruption by a large scorpion-derived pore-forming peptide.

    abstract::The membrane disruption mechanism of pandinin 1 (pin1), an antimicrobial peptide isolated from the venom of the African scorpion, was studied using 31P, 13C, 1H solid-state and multidimensional solution-state NMR spectroscopy. A high-resolution NMR solution structure of pin1 showed that the two distinct alpha-helical ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.070292

    authors: Nomura K,Ferrat G,Nakajima T,Darbon H,Iwashita T,Corzo G

    更新日期:2005-12-01 00:00:00

  • A transient excited state model for sodium permeability changes in excitable membranes.

    abstract::In this paper we explore the properties of a mathematical model for the passive sodium permeability system of excitable membranes. This model is distinguished by the explicit inclusion of a rate constant which depends not on instantaneous voltage, but on rate of voltage change. Actually, the model is a rather modest m...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(75)85840-1

    authors: Jakobsson E,Scudiero C

    更新日期:1975-06-01 00:00:00

  • Subthreshold oscillatory responses of the Hodgkin-Huxley cable model for the squid giant axon.

    abstract::The classical cable equation, in which membrane conductance is considered constant, is modified by including the linearized effect of membrane potential on sodium and potassium ionic currents, as formulated in the Hodgkin-Huxley equations for the squid giant axon. The resulting partial differential equation is solved ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(69)86446-5

    authors: Sabah NH,Leibovic KN

    更新日期:1969-10-01 00:00:00

  • Constitutive equations of skeletal muscle based on cross-bridge mechanism.

    abstract::The statistical mechanics of cross-bridge action is considered in order to develop constitutive equations that express fiber tension as a function of degree of activation and time history of speed of contraction. The kinetic equation of A.F. Huxley (1) is generalized to apply to the partially activated state. The rate...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/s0006-3495(85)83895-9

    authors: Tözeren A

    更新日期:1985-02-01 00:00:00

  • Effects of alkali cations on the nuclear magnetic resonance intensity of 23Na in rat liver homogenate.

    abstract::Effects of alkali cations on the nuclear magnetic resonance intensity of 23Na were studied in rat liver homogenate. The loss in the resonance intensity of 23Na in the homogenate was able to be divided into two components, one of which is abolished by the addition of Cs+ ("Cs-sensitive component"), the other being inse...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(76)85779-7

    authors: Monoi H

    更新日期:1976-12-01 00:00:00

  • Configurational entropy change of netropsin and distamycin upon DNA minor-groove binding.

    abstract::Binding of a small molecule to a macromolecular target reduces its conformational freedom, resulting in a negative entropy change that opposes the binding. The goal of this study is to estimate the configurational entropy change of two minor-groove-binding ligands, netropsin and distamycin, upon binding to the DNA dup...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.074617

    authors: Dolenc J,Baron R,Oostenbrink C,Koller J,van Gunsteren WF

    更新日期:2006-08-15 00:00:00

  • Endocytosis Is a Key Mode of Interaction between Extracellular β-Amyloid and the Cell Membrane.

    abstract::Interactions between amyloid-β peptide (Aβ) and the cell membrane include interaction with membrane lipids and binding to membrane receptors, both of which are considered to be the toxicity mechanisms of Aβ. However, it is unclear whether both mechanisms lead to cytotoxicity. Thus, we aimed to analyze these two mechan...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2020.07.035

    authors: Shi JM,Zhu L,Lan X,Zhao DW,He YJ,Sun ZQ,Wu D,Li HY

    更新日期:2020-09-15 00:00:00

  • Spot variation fluorescence correlation spectroscopy allows for superresolution chronoscopy of confinement times in membranes.

    abstract::Resolving the dynamical interplay of proteins and lipids in the live-cell plasma membrane represents a central goal in current cell biology. Superresolution concepts have introduced a means of capturing spatial heterogeneity at a nanoscopic length scale. Similar concepts for detecting dynamical transitions (superresol...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2011.04.035

    authors: Ruprecht V,Wieser S,Marguet D,Schütz GJ

    更新日期:2011-06-08 00:00:00

  • Hydroxide and proton migration in aquaporins.

    abstract::Hypothetical hydroxide and proton migration along the linear water chain in Aquaporin GlpF from Escherichia coli are studied by ab initio Car-Parrinello molecular dynamics simulations. It is found that the protein stabilizes a bipolar single file of water. The single file features a contiguous set of water-water hydro...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.104.058206

    authors: Jensen MØ,Röthlisberger U,Rovira C

    更新日期:2005-09-01 00:00:00

  • Microtubule assembly of isotypically purified tubulin and its mixtures.

    abstract::Numerous isotypes of the structural protein tubulin have now been characterized in various organisms and their expression offers a plausible explanation for observed differences affecting microtubule function in vivo. While this is an attractive hypothesis, there are only a handful of studies demonstrating a direct in...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.108.132233

    authors: Rezania V,Azarenko O,Jordan MA,Bolterauer H,Ludueña RF,Huzil JT,Tuszynski JA

    更新日期:2008-08-01 00:00:00

  • The importance of thermodynamic equilibrium for high throughput gene expression arrays.

    abstract::We present an analysis of physical chemical constraints on the accuracy of DNA micro-arrays under equilibrium and nonequilibrium conditions. At the beginning of the article we describe an algorithm for choosing a probe set with high specificity for targeted genes under equilibrium conditions. The algorithm as well as ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(03)74837-1

    authors: Bhanot G,Louzoun Y,Zhu J,DeLisi C

    更新日期:2003-01-01 00:00:00

  • Residues in Na(+) channel D3-S6 segment modulate both batrachotoxin and local anesthetic affinities.

    abstract::Batrachotoxin (BTX) alters the gating of voltage-gated Na(+) channels and causes these channels to open persistently, whereas local anesthetics (LAs) block Na(+) conductance. The BTX and LA receptors have been mapped to several common residues in D1-S6 and D4-S6 segments of the Na(+) channel alpha-subunit. We substitu...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(00)76390-9

    authors: Wang SY,Nau C,Wang GK

    更新日期:2000-09-01 00:00:00

  • Discrete membrane surface charge distributions. Effect of fluctuations near individual channels.

    abstract::Each gating mechanism controlling permeability in a membrane may be influenced by only a few charge binding sites on the membrane surface, so that fluctuations in the occupancy of these sites are important. Tow extreme cases arise. (a) The time scale of these fluctuations is much shorter than the gating time constant....

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(78)85426-5

    authors: Attwell D,Eisner D

    更新日期:1978-12-01 00:00:00

  • Mechanosensitive closed-closed transitions in large membrane proteins: osmoprotection and tension damping.

    abstract::Multiconformation membrane proteins are mechanosensitive (MS) if their conformations displace different bilayer areas. Might MS closed-closed transitions serve as tension buffers, that is, as membrane "spandex"? While bilayer expansion is effectively instantaneous, transitions of bilayer-embedded MS proteins are stoch...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2009.08.054

    authors: Boucher PA,Morris CE,Joós B

    更新日期:2009-11-18 00:00:00

  • Differential stability of beta-sheets and alpha-helices in beta-lactamase: a high temperature molecular dynamics study of unfolding intermediates.

    abstract::beta-Lactamase, which catalyzes beta-lactam antibiotics, is prototypical of large alpha/beta proteins with a scaffolding formed by strong noncovalent interactions. Experimentally, the enzyme is well characterized, and intermediates that are slightly less compact and having nearly the same content of secondary structur...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(93)81288-8

    authors: Vijayakumar S,Vishveshwara S,Ravishanker G,Beveridge DL

    更新日期:1993-12-01 00:00:00

  • Calmodulin binds a highly extended HIV-1 MA protein that refolds upon its release.

    abstract::Calmodulin (CaM) expression is upregulated upon HIV-1 infection and interacts with proteins involved in viral processing, including the multifunctional HIV-1 MA protein. We present here the results of studies utilizing small-angle neutron scattering with contrast variation that, when considered in the light of earlier...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2012.06.042

    authors: Taylor JE,Chow JYH,Jeffries CM,Kwan AH,Duff AP,Hamilton WA,Trewhella J

    更新日期:2012-08-08 00:00:00

  • Silent TWIK-1 potassium channels conduct monovalent cation currents.

    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

    pub_type: 信件

    doi:10.1016/j.bpj.2012.03.011

    authors: Ma L,Xie YP,Zhou M,Chen H

    更新日期:2012-04-18 00:00:00

  • Do All X-ray Structures of Protein-Ligand Complexes Represent Functional States? EPOR, a Case Study.

    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

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.12.042

    authors: Corbett MSP,Mark AE,Poger D

    更新日期:2017-02-28 00:00:00

  • Background Suppression in Imaging Gold Nanorods through Detection of Anti-Stokes Emission.

    abstract::Metallic nanoparticles have opened the possibility of imaging, tracking, and manipulating biological samples without time limitations. Their low photoluminescence quantum yield, however, makes them hard to detect under high background conditions. In this study we show that it is possible to image gold nanorods by dete...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.10.035

    authors: Carattino A,Keizer VIP,Schaaf MJM,Orrit M

    更新日期:2016-12-06 00:00:00

  • A simplified model of local structure in aqueous proline amino acid revealed by first-principles molecular dynamics simulations.

    abstract::Aqueous proline solutions are deceptively simple as they can take on complex roles such as protein chaperones, cryoprotectants, and hydrotropic agents in biological processes. Here, a molecular level picture of proline/water mixtures is developed. Car-Parrinello ab initio molecular dynamics (CPAIMD) simulations of aqu...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.108.134916

    authors: Troitzsch RZ,Tulip PR,Crain J,Martyna GJ

    更新日期:2008-12-01 00:00:00

  • Cross-correlated photon scattering during the photocycle of bacteriorhodopsin.

    abstract::Changes in the ultraviolet light scattering from a suspension of purple membrane fragments were detected during the photocycle of bacteriorhodopsin with a cross-correlation method. The scattered light intensity from a suspension of membrane fragments containing the protein bacteriorhodopsin was measured on a logarithm...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(90)82415-2

    authors: Czégé J,Reinisch L

    更新日期:1990-09-01 00:00:00

  • Photophysics of the fluorescent Ca2+ indicator Fura-2.

    abstract::The photophysics of the complex forming reaction of Ca2+ and Fura-2 are investigated using steady-state and time-resolved fluorescence measurements. The fluorescence decay traces were analyzed with global compartmental analysis yielding the following values for the rate constants at room temperature in aqueous solutio...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(95)80285-7

    authors: Van den Bergh V,Boens N,De Schryver FC,Ameloot M,Steels P,Gallay J,Vincent M,Kowalczyk A

    更新日期:1995-03-01 00:00:00

  • Analysis of the anisotropy decay of trans-parinaric acid in lipid bilayers.

    abstract::An analysis is presented of the complex anisotropy behavior of trans-parinaric acid in single component DEPC lipid bilayers. It is shown that a model involving two species with distinct lifetime and motional behavior is required, and is adequate, to explain the observed data. In particular, the observed increase in th...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(89)82909-1

    authors: Ruggiero A,Hudson B

    更新日期:1989-06-01 00:00:00

  • Environmental effects on the protonation states of active site residues in bacteriorhodopsin.

    abstract::Finite difference solutions of the Poisson-Boltzmann equation are used to calculate the pKa values of the functionally important ionizable groups in bacteriorhodopsin. There are strong charge-charge interactions between the residues in the binding site leading to the possibility of complex titration behavior. Structur...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(94)80925-7

    authors: Sampogna RV,Honig B

    更新日期:1994-05-01 00:00:00