32 results match your criteria PMC Biophysics [Journal]

  • Page 1 of 1

Combined use of steady-state fluorescence emission and anisotropy of merocyanine 540 to distinguish crystalline, gel, ripple, and liquid crystalline phases in dipalmitoylphosphatidylcholine bilayers.

PMC Biophys 2010 Nov 5;3(1):14. Epub 2010 Nov 5.

Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah 84602, USA.

The various lamellar phases of dipalmitoylphosphadtidylcholine bilayers with and without cholesterol were used to assess the versatility of the fluorescent probe merocyanine 540 through simultaneous measurements of emission intensity, spectral shape, and steady-state anisotropy. Induction of the crystalline phase (Lc') by pre-incubation at 4°C produced a wavelength dependence of anisotropy which was strong at 15 and 25°C, weak at 38°C, and minimal above the main transition (>~41.5°C) or after returning the temperature from 46 to 25°C. Read More

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http://dx.doi.org/10.1186/1757-5036-3-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2993649PMC
November 2010
10 Reads

Tubulohelical membrane arrays: From the initial observation to the elucidation of nanophysical properties and cellular function.

PMC Biophys 2010 Jun 28;3(1):13. Epub 2010 Jun 28.

Department of Biochemistry and Cell Biology, Max F, Perutz Laboratories, University of Vienna, Dr, Bohrgasse 9, A-1030 Vienna, Austria.

Lipids undergo self-assembly to form ordered nonlamellar, nanoperiodic arrays both in vitro and in vivo. While engineering of such membrane arrays for technical devices is envisaged, we know little about their cellular function. Do they represent building blocks of an inherent cellular nanotechnology? Prospects for answering this question could be improved if the nanophysical properties of the membrane arrays could be studied in the context of specific cellular functions. Read More

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http://dx.doi.org/10.1186/1757-5036-3-13DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2917399PMC
June 2010
2 Reads

Bistability in the actin cortex.

Authors:
Carsten Beta

PMC Biophys 2010 Jun 24;3(1):12. Epub 2010 Jun 24.

Institut für Physik und Astronomie, Universität Potsdam, 14476 Potsdam, Germany.

Multi-color fluorescence imaging experiments of wave forming Dictyostelium cells have revealed that actin waves separate two domains of the cell cortex that differ in their actin structure and phosphoinositide composition. We propose a bistable model of actin dynamics to account for these experimental observation. The model is based on the simplifying assumption that the actin cytoskeleton is composed of two distinct network types, a dendritic and a bundled network. Read More

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http://dx.doi.org/10.1186/1757-5036-3-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907310PMC
June 2010
2 Reads

Monte Carlo Simulations indicate that Chromati: Nanostructure is accessible by Light Microscopy.

PMC Biophys 2010 Jun 10;3:11. Epub 2010 Jun 10.

Institut für Theoretische Physik Universität Heidelberg Philosophenweg 19 D-69120 Heidelberg Germany.

A long controversy exists about the structure of chromatin. Theoretically, this structure could be resolved by scattering experiments if one determines the scattering function - or equivalently the pair distribution function - of the nucleosomes. Unfortunately, scattering experiments with live cells are very difficult and limited to only a couple of nucleosomes. Read More

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http://dx.doi.org/10.1186/1757-5036-3-11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2911407PMC
June 2010
2 Reads

Combined molecular dynamics and continuum solvent studies of the pre-pore Cry4Aa trimer suggest its stability in solution and how it may form pore.

PMC Biophys 2010 May 13;3(1):10. Epub 2010 May 13.

Theoretical and Computational Biophysics Laboratory, Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.

Cry4Aa toxin is one of the highly specific mosquito-larvicidal proteins produced by the bacterium Bacillus thuringiensis subspecies israelensis. It is thought to form pores in the larval midgut membrane that cause membrane leakage and subsequent insect death. Therefore, Cry4Aa and other Cry toxins have been used as efficient and safe bacterial insecticides to control the disease-carrying mosquitoes such as Aedes, Anopheles, and Culex. Read More

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http://dx.doi.org/10.1186/1757-5036-3-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3239330PMC
May 2010
1 Read

Live cell flattening - traditional and novel approaches.

PMC Biophys 2010 Apr 19;3(1). Epub 2010 Apr 19.

Max-Planck-Institut für Dynamik und Selbstorganisation, 37077 Göttingen, Germany.

Eukaryotic cell flattening is valuable for improving microscopic observations, ranging from bright field (BF) to total internal reflection fluorescence (TIRF) microscopy. Fundamental processes, such as mitosis and in vivo actin polymerization, have been investigated using these techniques. Here, we review the well known agar overlayer protocol and the oil overlay method. Read More

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http://dx.doi.org/10.1186/1757-5036-3-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873278PMC
April 2010
7 Reads

Probing the folding of mini-protein Beta3s by two-dimensional infrared spectroscopy; simulation study.

PMC Biophys 2010 Mar 19;3(1). Epub 2010 Mar 19.

Graduate Program in Biochemistry and Structural Biology, State University of New York at Stony Brook, New York, 11794-3400, USA.

We propose to use infrared coherent two-dimensional correlation spectroscopy (2DCS) to characterize the folding mechanism of the mini-protein Beta3s. In this study Beta3s was folded by molecular dynamics (MD) simulation and intermediate conformational ensembles were identified. The one and two-dimensional correlation spectrum was calculated for the intermediate and native states of the mini-protein. Read More

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http://dx.doi.org/10.1186/1757-5036-3-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851665PMC
March 2010
2 Reads

Self-organizing actin waves that simulate phagocytic cup structures.

Authors:
Günther Gerisch

PMC Biophys 2010 Mar 18;3(1). Epub 2010 Mar 18.

Max-Planck-Institut für Biochemie, Am Klopferspitz 18, D-82152 Martinsried, Germany.

This report deals with actin waves that are spontaneously generated on the planar, substrate-attached surface of Dictyostelium cells. These waves have the following characteristics. (1) They are circular structures of varying shape, capable of changing the direction of propagation. Read More

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http://dx.doi.org/10.1186/1757-5036-3-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2851664PMC
March 2010
5 Reads

Geometric constrains for detecting short actin filaments by cryogenic electron tomography.

PMC Biophys 2010 Mar 5;3(1). Epub 2010 Mar 5.

Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, D-69120 Heidelberg, Germany.

Polymerization of actin into filaments can push membranes forming extensions like filopodia or lamellipodia, which are important during processes such as cell motility and phagocytosis. Similarly, small organelles or pathogens can be moved by actin polymerization. Such actin filaments can be arranged in different patterns and are usually hundreds of nanometers in length as revealed by various electron microscopy approaches. Read More

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http://dx.doi.org/10.1186/1757-5036-3-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2844354PMC
March 2010
1 Read

Nanoscopy of the cellular response to hypoxia by means of fluorescence resonance energy transfer (FRET) and new FRET software.

PMC Biophys 2010 Mar 5;3(1). Epub 2010 Mar 5.

Institut für Physiologie, Universität Duisburg-Essen, D-45122 Essen, Germany.

Background: Cellular oxygen sensing is fundamental to all mammalian cells to adequately respond to a shortage of oxygen by increasing the expression of genes that will ensure energy homeostasis. The transcription factor Hypoxia-Inducible-Factor-1 (HIF-1) is the key regulator of the response because it coordinates the expression of hypoxia inducible genes. The abundance and activity of HIF-1 are controlled through posttranslational modification by hydroxylases, the cellular oxygen sensors, of which the activity is oxygen dependent. Read More

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http://dx.doi.org/10.1186/1757-5036-3-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2846870PMC
March 2010
11 Reads

Two-color STED microscopy reveals different degrees of colocalization between hexokinase-I and the three human VDAC isoforms.

PMC Biophys 2010 Mar 5;3(1). Epub 2010 Mar 5.

Max Planck Institute for Biophysical Chemistry, Department of NanoBiophotonics, Am Fassberg 11, 37077 Göttingen, Germany.

The voltage-dependent anion channel (VDAC, also known as mitochondrial porin) is the major transport channel mediating the transport of metabolites, including ATP, across the mitochondrial outer membrane. Biochemical data demonstrate the binding of the cytosolic protein hexokinase-I to VDAC, facilitating the direct access of hexokinase-I to the transported ATP. In human cells, three hVDAC isoforms have been identified. Read More

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http://dx.doi.org/10.1186/1757-5036-3-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2838807PMC
March 2010
4 Reads

Assembly dynamics of PML nuclear bodies in living cells.

PMC Biophys 2010 Mar 5;3(1). Epub 2010 Mar 5.

Leibniz-Institute of Age Research, Fritz-Lipman-Institute, Beutenbergstr, 11, 07745 Jena, Germany.

The mammalian cell nucleus contains a variety of organelles or nuclear bodies which contribute to key nuclear functions. Promyelocytic leukemia nuclear bodies (PML NBs) are involved in the regulation of apoptosis, antiviral responses, the DNA damage response and chromatin structure, but their precise biochemical function in these nuclear pathways is unknown. One strategy to tackle this problem is to assess the biophysical properties of the component parts of these macromolecular assemblies in living cells. Read More

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http://dx.doi.org/10.1186/1757-5036-3-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2854101PMC
March 2010
23 Reads

Conformational preference of ChaK1 binding peptides: a molecular dynamics study.

PMC Biophys 2010 Jan 21;3(1). Epub 2010 Jan 21.

Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.

TRPM7/ChaK1 is a recently discovered atypical protein kinase that has been suggested to selectively phosphorylate the substrate residues located in alpha-helices. However, the actual structure of kinase-substrate complex has not been determined experimentally and the recognition mechanism remains unknown. In this work we explored possible kinase-substrate binding modes and the likelihood of an alpha-helix docking interaction, within a kinase active site, using molecular modeling. Read More

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http://dx.doi.org/10.1186/1757-5036-3-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831825PMC
January 2010
2 Reads

Kinetics of diffusion-controlled enzymatic reactions with charged substrates.

PMC Biophys 2010 Jan 18;3. Epub 2010 Jan 18.

State Key Laboratory of Scientific/Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China.

The Debye-Hückel limiting law (DHL) has often been used to estimate rate constants of diffusion-controlled reactions under different ionic strengths. Two main approximations are adopted in DHL: one is that the solution of the linearized Poisson-Boltzmann equation for a spherical cavity is used to estimate the excess electrostatic free energy of a solution; the other is that details of electrostatic interactions of the solutes are neglected. This makes DHL applicable only at low ionic strengths and dilute solutions (very low substrate/solute concentrations). Read More

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http://dx.doi.org/10.1186/1757-5036-3-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2821377PMC
January 2010
1 Read

Inverse tuning of metal binding affinity and protein stability by altering charged coordination residues in designed calcium binding proteins.

PMC Biophys 2009 Dec 21;2:11. Epub 2009 Dec 21.

Department of Chemistry, Center for Drug Design and Biotechnology, Georgia State University, Atlanta, GA 30303, USA.

Ca(2+ )binding proteins are essential for regulating the role of Ca(2+ )in cell signaling and maintaining Ca(2+ )homeostasis. Negatively charged residues such as Asp and Glu are often found in Ca(2+ )binding proteins and are known to influence Ca(2+ )binding affinity and protein stability. In this paper, we report a systematic investigation of the role of local charge number and type of coordination residues in Ca(2+ )binding and protein stability using de novo designed Ca(2+ )binding proteins. Read More

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http://dx.doi.org/10.1186/1757-5036-2-11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2816670PMC
December 2009
3 Reads

Amplitude distribution of stochastic oscillations in biochemical networks due to intrinsic noise.

PMC Biophys 2009 Nov 17;2(1):10. Epub 2009 Nov 17.

Institute for Systems Theory and Automatic Control, Universität Stuttgart, Pfaffenwaldring 9, 70569 Stuttgart, Germany.

Intrinsic noise is a common phenomenon in biochemical reaction networks and may affect the occurence and amplitude of sustained oscillations in the states of the network. To evaluate properties of such oscillations in the time domain, it is usually required to conduct long-term stochastic simulations, using for example the Gillespie algorithm. In this paper, we present a new method to compute the amplitude distribution of the oscillations without the need for long-term stochastic simulations. Read More

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http://dx.doi.org/10.1186/1757-5036-2-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796987PMC
November 2009
2 Reads

Two-dimensional nanosecond electric field mapping based on cell electropermeabilization.

PMC Biophys 2009 Nov 11;2(1). Epub 2009 Nov 11.

Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA.

Nanosecond, megavolt-per-meter electric pulses cause permeabilization of cells to small molecules, programmed cell death (apoptosis) in tumor cells, and are under evaluation as a treatment for skin cancer. We use nanoelectroporation and fluorescence imaging to construct two-dimensional maps of the electric field associated with delivery of 15 ns, 10 kV pulses to monolayers of the human prostate cancer cell line PC3 from three different electrode configurations: single-needle, five-needle, and flat-cut coaxial cable. Influx of the normally impermeant fluorescent dye YO-PRO-1 serves as a sensitive indicator of membrane permeabilization. Read More

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http://dx.doi.org/10.1186/1757-5036-2-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2779789PMC
November 2009
2 Reads

Simple modeling of FtsZ polymers on flat and curved surfaces: correlation with experimental in vitro observations.

PMC Biophys 2009 Oct 22;2(1). Epub 2009 Oct 22.

Instituto de Catálisis y Petroleoquímica, CSIC C/Marie Curie, 2, Cantoblanco, Madrid, E-28049, Spain.

FtsZ is a GTPase that assembles at midcell into a dynamic ring that constricts the membrane to induce cell division in the majority of bacteria, in many archea and several organelles. In vitro, FtsZ polymerizes in a GTP-dependent manner forming a variety of filamentous flexible structures. Based on data derived from the measurement of the in vitro polymerization of Escherichia coli FtsZ cell division protein we have formulated a model in which the fine balance between curvature, flexibility and lateral interactions accounts for structural and dynamic properties of the FtsZ polymers observed with AFM. Read More

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http://dx.doi.org/10.1186/1757-5036-2-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2776577PMC
October 2009
3 Reads

The influence of membrane physical properties on microvesicle release in human erythrocytes.

PMC Biophys 2009 Aug 24;2(1). Epub 2009 Aug 24.

Department of Physiology and Developmental Biology, Brigham Young University Provo, Utah 84602, USA.

Exposure of human erythrocytes to elevated intracellular calcium causes fragments of the cell membrane to be shed as microvesicles. This study tested the hypothesis that microvesicle release depends on microscopic membrane physical properties such as lipid order, fluidity, and composition. Membrane properties were manipulated by varying the experimental temperature, membrane cholesterol content, and the activity of the trans-membrane phospholipid transporter, scramblase. Read More

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http://dx.doi.org/10.1186/1757-5036-2-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2739839PMC
August 2009
8 Reads

Zwanzig-Mori projection operators and EEG dynamics: deriving a simple equation of motion.

PMC Biophys 2009 Jul 13;2(1). Epub 2009 Jul 13.

Department of Neurology, University of Wisconsin, Madison WI, USA.

We present a macroscopic theory of electroencephalogram (EEG) dynamics based on the laws of motion that govern atomic and molecular motion. The theory is an application of Zwanzig-Mori projection operators. The result is a simple equation of motion that has the form of a generalized Langevin equation (GLE), which requires knowledge only of macroscopic properties. Read More

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http://dx.doi.org/10.1186/1757-5036-2-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728514PMC
July 2009
2 Reads

Structural and functional implications of p53 missense cancer mutations.

Authors:
Yuhong Tan Ray Luo

PMC Biophys 2009 Jun 26;2(1). Epub 2009 Jun 26.

Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA.

Most human cancers contain mutations in the transcription factor p53 and majority of these are missense and located in the DNA binding core domain. In this study, the stabilities of all core domain missense mutations are predicted and are used to infer their likely inactivation mechanisms. Overall, 47. Read More

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http://dx.doi.org/10.1186/1757-5036-2-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2709103PMC
June 2009
1 Read

Three-dimensional studies of pathogenic peptides from the c-terminal of Trypanosoma cruzi ribosomal P proteins and their interaction with a monoclonal antibody structural model.

PMC Biophys 2009 May 27;2(1). Epub 2009 May 27.

Instituto de Matemática Aplicada de San Luis, CONICET, Ejército de los Andes 950, primer piso, 5700, San Luis, Argentina.

The acidic C-terminal peptides from Trypanosoma cruzi ribosomal P proteins are the major target of the antibody response in patients suffering Chagas chronic heart disease. It has been proposed that the disease is triggered by the cross-reaction of these antibodies with the second extra cellular loop of the beta1-adrenoreceptor, brought about by the molecular mimicry between the acidic C-terminal peptides and the receptor's loop. To improve the understanding of the structural basis of the autoimmune response against heart receptors, the 3-dimensional structure of the C-terminal peptides of Trypanosoma cruzi ribosomal proteins P0 (EDDDDDFGMGALF) and P2beta (EEEDDDMGFGLFD) were solved using the Electrostaticaly Driven MonteCarlo method. Read More

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http://dx.doi.org/10.1186/1757-5036-2-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2704175PMC
May 2009
3 Reads

The multiple faces of self-assembled lipidic systems.

PMC Biophys 2009 Apr 17;2(1). Epub 2009 Apr 17.

Laboratoire de Physique des Solides, Université Paris-Sud, CNRS, UMR 8502, F-91405 Orsay Cedex, France.

Lipids, the building blocks of cells, common to every living organisms, have the propensity to self-assemble into well-defined structures over short and long-range spatial scales. The driving forces have their roots mainly in the hydrophobic effect and electrostatic interactions. Membranes in lamellar phase are ubiquitous in cellular compartments and can phase-separate upon mixing lipids in different liquid-crystalline states. Read More

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http://dx.doi.org/10.1186/1757-5036-2-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2695813PMC
April 2009
3 Reads

An effective all-atom potential for proteins.

PMC Biophys 2009 Apr 8;2(1). Epub 2009 Apr 8.

Computational Biology & Biological Physics, Department of Theoretical Physics, Lund University, Sölvegatan 14A, SE-223 62 Lund, Sweden.

We describe and test an implicit solvent all-atom potential for simulations of protein folding and aggregation. The potential is developed through studies of structural and thermodynamic properties of 17 peptides with diverse secondary structure. Results obtained using the final form of the potential are presented for all these peptides. Read More

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http://dx.doi.org/10.1186/1757-5036-2-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2696411PMC
April 2009
5 Reads

Membrane protein dynamics: limited lipid control.

PMC Biophys 2009 Feb 6;2(1). Epub 2009 Feb 6.

Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, H-6701 Szeged, Temesvári krt, 62, P,O,B, 521, Hungary.

Correlation of lipid disorder with membrane protein dynamics has been studied with infrared spectroscopy, by combining data characterizing lipid phase, protein structure and, via hydrogen-deuterium (H/D) exchange, protein dynamics. The key element was a new measuring scheme, by which the combined effects of time and temperature on the H/D exchange could be separated. Cyanobacterial and plant thylakoid membranes, mammalian mitochondria membranes, and for comparison, lysozyme were investigated. Read More

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http://dx.doi.org/10.1186/1757-5036-2-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666629PMC
February 2009
4 Reads

Robustness, dissipations and coherence of the oscillation of circadian clock: potential landscape and flux perspectives.

PMC Biophys 2008 Dec 30;1(1). Epub 2008 Dec 30.

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, PR China.

Finding the global probabilistic nature of a non-equilibrium circadian clock is essential for addressing important issues of robustness and function. We have uncovered the underlying potential energy landscape of a simple cyanobacteria biochemical network, and the corresponding flux which is the driving force for the oscillation. We found that the underlying potential landscape for the oscillation in the presence of small statistical fluctuations is like an explicit ring valley or doughnut shape in the three dimensional protein concentration space. Read More

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http://dx.doi.org/10.1186/1757-5036-1-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667439PMC
December 2008
2 Reads

Resolution of complex fluorescence spectra of lipids and nicotinic acetylcholine receptor by multivariate analysis reveals protein-mediated effects on the receptor's immediate lipid microenvironment.

PMC Biophys 2008 Dec 18;1(1). Epub 2008 Dec 18.

UNESCO Chair of Biophysics and Molecular Neurobiology and Instituto de Investigaciones Bioquímicas de Bahía Blanca, B8000FWB Bahía Blanca, Argentina.

Analysis of fluorescent spectra from complex biological systems containing various fluorescent probes with overlapping emission bands is a challenging task. Valuable information can be extracted from the full spectra, however, by using multivariate analysis (MA) of measurements at different wavelengths. We applied MA to spectral data of purified Torpedo nicotinic acetylcholine receptor (AChR) protein reconstituted into liposomes made up of dioleoylphosphatidic acid (DOPA) and dioleoylphosphatidylcholine (DOPC) doped with two extrinsic fluorescent probes (NBD-cholesterol/pyrene-PC). Read More

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http://dx.doi.org/10.1186/1757-5036-1-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666634PMC
December 2008
2 Reads

Stochastic reconstruction of protein structures from effective connectivity profiles.

PMC Biophys 2008 Nov 26;1(1). Epub 2008 Nov 26.

Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstrasse 6, 64289 Darmstadt, Germany.

We discuss a stochastic approach for reconstructing the native structures of proteins from the knowledge of the "effective connectivity", which is a one-dimensional structural profile constructed as a linear combination of the eigenvectors of the contact map of the target structure. The structural profile is used to bias a search of the conformational space towards the target structure in a Monte Carlo scheme operating on a Calpha-chain of uniform, finite thickness. Structure information thus enters the folding dynamics via the effective connectivity, but the interaction is not restricted to pairs of amino acids that form native contacts, resulting in a free energy landscape which does not rely on the assumption of minimal frustration. Read More

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http://dx.doi.org/10.1186/1757-5036-1-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666633PMC
November 2008
2 Reads

Label-free electrical quantification of the dielectrophoretic response of DNA.

PMC Biophys 2008 Nov 5;1(1). Epub 2008 Nov 5.

Fraunhofer Institute for Biomedical Engineering, Am Mühlenberg 13, 14476 Potsdam-Golm, Germany.

A purely electrical sensing scheme is presented that determines the concentration of macromolecules in solution by measuring the capacitance between planar microelectrodes. Concentrations of DNA in the ng/mL range have been used in samples of 1 muL volume. The method has been applied to the characterisation of the dielectrophoretic response of DNA without the need for any chemical modifications. Read More

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http://dx.doi.org/10.1186/1757-5036-1-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666632PMC
November 2008
1 Read

ATR-FTIR spectroscopy detects alterations induced by organotin(IV) carboxylates in MCF-7 cells at sub-cytotoxic/-genotoxic concentrations.

PMC Biophys 2008 Nov 5;1(1). Epub 2008 Nov 5.

Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA1 4YQ, UK.

The environmental impact of metal complexes such as organotin(IV) compounds is of increasing concern. Genotoxic effects of organotin(IV) compounds (0.01 mug/ml, 0. Read More

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http://dx.doi.org/10.1186/1757-5036-1-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666631PMC
November 2008
3 Reads

On the electrostatic component of protein-protein binding free energy.

PMC Biophys 2008 Nov 5;1(1). Epub 2008 Nov 5.

Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634, USA.

Calculations of electrostatic properties of protein-protein complexes are usually done within framework of a model with a certain set of parameters. In this paper we present a comprehensive statistical analysis of the sensitivity of the electrostatic component of binding free energy (DeltaDeltaGel) with respect with different force fields (Charmm, Amber, and OPLS), different values of the internal dielectric constant, and different presentations of molecular surface (different values of the probe radius). The study was done using the largest so far set of entries comprising 260 hetero and 2148 homo protein-protein complexes extracted from a previously developed database of protein complexes (ProtCom). Read More

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http://dx.doi.org/10.1186/1757-5036-1-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2666630PMC
November 2008
1 Read

The debut of PMC Biophysics.

Authors:
Huan-Xiang Zhou

PMC Biophys 2008 Nov 5;1(1). Epub 2008 Nov 5.

Editor-in-Chief, PMC Biophysics, Department of Physics and Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA.

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http://dx.doi.org/10.1186/1757-5036-1-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2605105PMC
November 2008
2 Reads
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