Torsion profiling of proteins using magnetic particles.


:We report a method to profile the torsional spring properties of proteins as a function of the angle of rotation. The torque is applied by superparamagnetic particles and has been calibrated while taking account of the magnetization dynamics of the particles. We record and compare the torsional profiles of single Protein G-Immunoglobulin G (IgG) and IgG-IgG complexes, sandwiched between a substrate and a superparamagnetic particle, for torques in the range between 0.5 × 10(3) and 5 × 10(3) pN·nm. Both molecular systems show torsional stiffening for increasing rotation angle, but the elastic and inelastic torsion stiffnesses are remarkably different. We interpret the results in terms of the structural properties of the molecules. The torsion profiling technique opens new dimensions for research on biomolecular characterization and for research on bio-nanomechanical structure-function relationships.


Biophys J


Biophysical journal


van Reenen A,Gutiérrez-Mejía F,van IJzendoorn LJ,Prins MW




Has Abstract


2013-03-05 00:00:00














  • Mechanisms of cardiac cell excitation with premature monophasic and biphasic field stimuli: a model study.

    abstract::The mechanisms by which extracellular electric field stimuli induce the (re)excitation of cardiac cells in various stages of refractoriness are still not well understood. We modeled the interactions between an isolated cardiac cell and imposed extracellular electric fields to determine the mechanisms by which relative...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Fishler MG,Sobie EA,Thakor NV,Tung L

    更新日期:1996-03-01 00:00:00

  • Energy landscape of the prion protein helix 1 probed by metadynamics and NMR.

    abstract::The characterization of the structural dynamics of proteins, including those that present a substantial degree of disorder, is currently a major scientific challenge. These dynamics are biologically relevant and govern the majority of functional and pathological processes. We exploited a combination of enhanced molecu...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Camilloni C,Schaal D,Schweimer K,Schwarzinger S,De Simone A

    更新日期:2012-01-04 00:00:00

  • The molecular basis of the solution properties of hyaluronan investigated by confocal fluorescence recovery after photobleaching.

    abstract::Hyaluronan (HA) is a highly hydrated polyanion, which is a network-forming and space-filling component in the extracellular matrix of animal tissues. Confocal fluorescence recovery after photobleaching (confocal-FRAP) was used to investigate intramolecular hydrogen bonding and electrostatic interactions in hyaluronan ...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Gribbon P,Heng BC,Hardingham TE

    更新日期:1999-10-01 00:00:00

  • Condensed complexes and the calorimetry of cholesterol-phospholipid bilayers.

    abstract::A recent thermodynamic model describes a reversible reaction between cholesterol (C) and phospholipid (P) to form a condensed complex C(nq)P(np). Here q and p are relatively prime integers used to define the stoichiometric composition, and n is a measure of cooperativity. The present study applies this model to the sc...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Anderson TG,McConnell HM

    更新日期:2001-11-01 00:00:00

  • A cell-based model exhibiting branching and anastomosis during tumor-induced angiogenesis.

    abstract::This work describes the first cell-based model of tumor-induced angiogenesis. At the extracellular level, the model describes diffusion, uptake, and decay of tumor-secreted pro-angiogenic factor. At the cellular level, the model uses the cellular Potts model based on system-energy reduction to describe endothelial cel...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Bauer AL,Jackson TL,Jiang Y

    更新日期:2007-05-01 00:00:00

  • An anionic phospholipid enables the hydrophobic surfactant proteins to alter spontaneous curvature.

    abstract::The hydrophobic surfactant proteins, SP-B and SP-C, greatly accelerate the adsorption of the surfactant lipids to an air/water interface. Previous studies of factors that affect curvature suggest that vesicles may adsorb via a rate-limiting structure with prominent negative curvature, in which the hydrophilic face of ...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Chavarha M,Loney RW,Rananavare SB,Hall SB

    更新日期:2013-02-05 00:00:00

  • A quantitative model of thermal stabilization and destabilization of proteins by ligands.

    abstract::Equilibrium binding ligands usually increase protein thermal stability by an amount proportional to the concentration and affinity of the ligand. High-throughput screening for the discovery of drug-like compounds uses an assay based on thermal stabilization. The mathematical description of this stabilization is well d...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Cimmperman P,Baranauskiene L,Jachimoviciūte S,Jachno J,Torresan J,Michailoviene V,Matuliene J,Sereikaite J,Bumelis V,Matulis D

    更新日期:2008-10-01 00:00:00

  • Order in phospholipid Langmuir-Blodgett monolayers determined by total internal reflection fluorescence.

    abstract::Orientational order parameters of two diphenylhexatriene (DPH)-based fluorescent probes, 2-(3-(diphenylhexatrienyl)propanoyl)-1-hexadecanoyl-sn-glycero-3-p hosphocholine (DPHpPC) and 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), in dipalmitoylphosphatidylcholine (DPPC) Langmuir-Blodgett monolayers...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Zhai X,Kleijn JM

    更新日期:1997-06-01 00:00:00

  • Volume and enthalpy changes in the early steps of bacteriorhodopsin photocycle studied by time-resolved photoacoustics.

    abstract::We have studied the photoinduced volume changes, energetics, and kinetics in the early steps of the bacteriorhodopsin (BR) photocycle with pulsed, time-resolved photoacoustics. Our data show that there are two volume changes. The fast volume change ( < or = 200 ns) is an expansion (2.5 +/- 0.3 A3/molecule) and is obse...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Zhang D,Mauzerall D

    更新日期:1996-07-01 00:00:00

  • An intramolecular hydrogen bond with large proton polarizability within the head group of phosphatidylserine. An infrared investigation.

    abstract::Films of O-phospho-L-serine-P-ethylester (PSE) were studied by infrared spectroscopy. PSE films were studied pure and as 1:1 mixture with LiOH, NaOH, KOH, and Ca(OH)2 as a function of the degree of hydration. The same investigations were performed if (L-glu)n was added to the system (ratio 1:1, PSE/glu residue). In th...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Leberle K,Kempf I,Zundel G

    更新日期:1989-04-01 00:00:00

  • Neuronal SNAREs do not trigger fusion between synthetic membranes but do promote PEG-mediated membrane fusion.

    abstract::At low surface concentrations that permit formation of impermeable membranes, neuronal soluble N-ethyl maleimide sensitive factor attachment protein receptor (SNARE) proteins form a stable, parallel, trans complex when vesicles are brought into contact by a low concentration of poly(ethylene glycol) (PEG). Surprisingl...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Dennison SM,Bowen ME,Brunger AT,Lentz BR

    更新日期:2006-03-01 00:00:00

  • Purification of the small mechanosensitive channel of Escherichia coli (MscS): the subunit structure, conduction, and gating characteristics in liposomes.

    abstract::The small mechanosensitive channel, MscS, is a part of the turgor-driven solute efflux system that protects bacteria from lysis in the event of osmotic downshift. It has been identified in Escherichia coli as a product of the orphan yggB gene, now called mscS (Levina et al., 1999, EMBO J. 18:1730). Here I show that th...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Sukharev S

    更新日期:2002-07-01 00:00:00

  • High-resolution conformation and backbone dynamics of a soluble aggregate of apomyoglobin119.

    abstract::The structure and dynamics of soluble misfolded aggregates are poorly understood, despite their importance in protein science and disease. Water-soluble self-associated species that do not become insoluble over time are invaluable tools for high-resolution conformational studies aimed at dissecting the determinants of...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Rajagopalan S,Kurt N,Cavagnero S

    更新日期:2011-02-02 00:00:00

  • Reversing nerve cell pathology by optimizing modulatory action on target ion channels.

    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

    pub_type: 杂志文章


    authors: Tigerholm J,Fransén E

    更新日期:2011-10-19 00:00:00

  • 1H and (13)C NMR of multilamellar dispersions of polyunsaturated (22:6) phospholipids.

    abstract::The polyunsaturated fatty acid docosahexaenoic acid (DHA) makes up approximately 50% of the lipid chains in the retinal rod outer segment disk membranes and a large fraction of the lipid chains in the membranes of neuronal tissues. There is an extensive literature concerned with the dietary requirements for essential ...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Everts S,Davis JH

    更新日期:2000-08-01 00:00:00

  • Fibril formation of the rabbit/human/bovine prion proteins.

    abstract::Prion diseases are infectious fatal neurodegenerative diseases including Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy in cattle. The misfolding and conversion of cellular PrP in such mammals into pathogenic PrP is believed to be the key procedure. Rabbits are among the few mammalian species...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Zhou Z,Yan X,Pan K,Chen J,Xie ZS,Xiao GF,Yang FQ,Liang Y

    更新日期:2011-09-21 00:00:00

  • Functional properties of the Drosophila melanogaster inositol 1,4,5-trisphosphate receptor mutants.

    abstract::The inositol (1,4,5)-trisphosphate receptor (InsP(3)R) is an intracellular calcium (Ca(2+)) release channel that plays a crucial role in cell signaling. In Drosophila melanogaster a single InsP(3)R gene (itpr) encodes a protein (DmInsP(3)R) that is approximately 60% conserved with mammalian InsP(3)Rs. A number of itpr...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Srikanth S,Wang Z,Tu H,Nair S,Mathew MK,Hasan G,Bezprozvanny I

    更新日期:2004-06-01 00:00:00

  • The temperature dependence of lipid membrane permeability, its quantized nature, and the influence of anesthetics.

    abstract::We investigate the permeability of lipid membranes for fluorescence dyes and ions. We find that permeability reaches a maximum close to the chain melting transition of the membranes. Close to transitions, fluctuations in area and compressibility are high, leading to an increased likelihood of spontaneous lipid pore fo...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Blicher A,Wodzinska K,Fidorra M,Winterhalter M,Heimburg T

    更新日期:2009-06-03 00:00:00

  • Multiple channels mediate calcium leakage in the A7r5 smooth muscle-derived cell line.

    abstract::Ca2+ entry under resting conditions may be important for contraction of vascular smooth muscle, but little is known about the mechanisms involved. Ca2+ leakage was studied in the A7r5 smooth muscle-derived cell line by patch-clamp techniques. Two channels that could mediate calcium influx at resting membrane potential...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Obejero-Paz CA,Jones SW,Scarpa A

    更新日期:1998-09-01 00:00:00

  • Transfer of rolf S3-S4 linker to HERG eliminates activation gating but spares inactivation.

    abstract::Studies in Shaker, a voltage-dependent potassium channel, suggest a coupling between activation and inactivation. This coupling is controversial in hERG, a fast-inactivating voltage-dependent potassium channel. To address this question, we transferred to hERG the S3-S4 linker of the voltage-independent channel, rolf, ...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Choveau FS,El Harchi A,Rodriguez N,Louérat-Oriou B,Baró I,Demolombe S,Charpentier F,Loussouarn G

    更新日期:2009-09-02 00:00:00

  • Continuous allosteric regulation of a viral packaging motor by a sensor that detects the density and conformation of packaged DNA.

    abstract::We report evidence for an unconventional type of allosteric regulation of a biomotor. We show that the genome-packaging motor of phage ϕ29 is regulated by a sensor that detects the density and conformation of the DNA packaged inside the viral capsid, and slows the motor by a mechanism distinct from the effect of a dir...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Berndsen ZT,Keller N,Smith DE

    更新日期:2015-01-20 00:00:00

  • Interruptions in single strands of the DNA in slime mold and other organisms.

    abstract::The molecular weight of single-stranded DNA from the slime mold Physarum polycephalum has been determined by alkaline gradient centrifugation. The average molecular weight during DNA synthesis ( approximately 1.5 x 10(7) D) is less than that observed in nonsynthetic periods ( approximately 4 x 10(7) D). On the basis o...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: McGrath RA,Williams RW

    更新日期:1967-05-01 00:00:00

  • Three-dimensional dynamic structure of the liquid-ordered domain in lipid membranes as examined by pulse-EPR oxygen probing.

    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

    pub_type: 杂志文章


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

    更新日期:2007-03-01 00:00:00

  • Synchronization of pancreatic islet oscillations by intrapancreatic ganglia: a modeling study.

    abstract::Plasma insulin measurements from mice, rats, dogs, and humans indicate that insulin levels are oscillatory, reflecting pulsatile insulin secretion from individual islets. An unanswered question, however, is how the activity of a population of islets is coordinated to yield coherent oscillations in plasma insulin. Here...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Fendler B,Zhang M,Satin L,Bertram R

    更新日期:2009-08-05 00:00:00

  • An approach for time-resolved x-ray scattering.

    abstract::Recent biological optical spectroscopic studies have correlated discrete spectroscopic states with biological function in several systems. One of the challenges of molecular biophysics is to correlate structural changes with these spectroscopic states. From small-angle x-ray scattering one can obtain a key structural ...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Stamatoff J

    更新日期:1979-05-01 00:00:00

  • Electrochemical healing similarities between animals and plants.

    abstract::A brief summary of the major results in enhanced wound healing by electrolysis in animals and humans is presented along with the results of enhanced growth by electrolysis in plants. Hypotheses of normal and enhanced wound healing in animal and plants are reviewed. A comparison of the experimental results indicates st...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Gensler W

    更新日期:1979-09-01 00:00:00

  • Analytic binding isotherms describing competitive interactions of a protein ligand with specific and nonspecific sites on the same DNA oligomer.

    abstract::Many studies of specific protein-nucleic acid binding use short oligonucleotides or restriction fragments, in part to minimize the potential for nonspecific binding of the protein. However, when the specificity ratio is low, multiple nonspecifically bound proteins may occupy the region of DNA corresponding to one spec...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Tsodikov OV,Holbrook JA,Shkel IA,Record MT Jr

    更新日期:2001-10-01 00:00:00

  • Confocal FRET microscopy to measure clustering of ligand-receptor complexes in endocytic membranes.

    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

    pub_type: 杂志文章


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

    更新日期:2003-07-01 00:00:00

  • The transmembrane domain peptide of vesicular stomatitis virus promotes both intermediate and pore formation during PEG-mediated vesicle fusion.

    abstract::We propose mechanisms by which the transmembrane domain of vesicular stomatitis virus (VSV-TMD) promotes both initiation of fusion and formation of a fusion pore. Time courses of polyethyleneglycol (PEG)-mediated fusion of 25 nm small unilamellar vesicles composed of dioleoylphosphatidylcholine, dioleoylphosphatidylet...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Sengupta T,Chakraborty H,Lentz BR

    更新日期:2014-09-16 00:00:00

  • Analytical description of the activation of multi-state receptors by continuous neurotransmitter signals at brain synapses.

    abstract::Chemical synaptic transmission is a fundamental component of interneuronal communications in the central nervous system (CNS). Discharge of a presynaptic vesicle containing a few thousand molecules (a quantum) of neurotransmitter into the synaptic cleft generates a transmitter concentration signal that drives postsyna...

    journal_title:Biophysical journal

    pub_type: 杂志文章


    authors: Uteshev VV,Pennefather PS

    更新日期:1997-03-01 00:00:00