Cooperative structural transitions induced by non-homogeneous intramolecular interactions in compact globular proteins.

abstract：:We have used admittance analysis together with the black lipid membrane technique to analyze electrogenic reactions within the Na(+) branch of the reaction cycle of the Na(+)/K(+)-ATPase. ATP release by flash photolysis of caged ATP induced changes in the admittance of the compound membrane system that are associated ...

journal_title：Biophysical journal

authors： Babes A,Fendler K

更新日期：2000-11-01 00:00:00

abstract：:Small angle x-ray and neutron scattering are techniques that give solution structures for large macromolecules. The creation of physically realistic atomistic models from known high-resolution structures to determine joint x-ray and neutron scattering best-fit structures offers a, to our knowledge, new method that sig...

journal_title：Biophysical journal

authors： Wright DW,Elliston ELK,Hui GK,Perkins SJ

更新日期：2019-12-03 00:00:00

abstract：:The effect of peptides, corresponding to sequences in the skeletal muscle dihydropyridine receptor II-III loop, on Ca(2+) release from sarcoplasmic reticulum (SR) and on ryanodine receptor (RyR) calcium release channels have been compared in preparations from normal and malignant hyperthermia (MH)-susceptible pigs. Pe...

journal_title：Biophysical journal

authors： Gallant EM,Curtis S,Pace SM,Dulhunty AF

更新日期：2001-04-01 00:00:00

abstract：:In cardiac tissue, during partial blockade of the membrane sodium channels, or at high frequencies of excitation, inexcitable obstacles with sharp edges may destabilize the propagation of electrical excitation waves, causing the formation of self-sustained vortices and turbulent cardiac electrical activity. The format...

journal_title：Biophysical journal

authors： Cabo C,Pertsov AM,Davidenko JM,Baxter WT,Gray RA,Jalife J

更新日期：1996-03-01 00:00:00

abstract：:We modeled two different mechanisms, a shunting conductance and a slow sodium inactivation, to test whether they could modulate the active propagation of a train of action potentials in a dendritic tree. Computer simulations, using a compartmental model of a pyramidal neuron, suggest that each of these two mechanisms ...

journal_title：Biophysical journal

authors： Migliore M

更新日期：1996-11-01 00:00:00

abstract：:Apparent diffusion coefficient (ADC) measurement in the lung using gas magnetic resonance imaging is a promising technique with potential for reflecting changes in lung microstructure. Despite some recent impressive human applications, full interpretation of ADC measures remains an elusive goal, due to a lack of detai...

journal_title：Biophysical journal

authors： Pérez-Sánchez JM,Rodríguez I,Ruiz-Cabello J

更新日期：2009-07-22 00:00:00

abstract：:Previous studies have demonstrated a calcium-dependent interaction of calmodulin (CaM) and Fas that is regulated during Fas-induced apoptosis in several cell lines, including cholangiocarcinoma, Jurkat cells, and osteoclasts. The binding of CaM and Fas has been identified on residues 231-254 of Fas; the V254N point mu...

journal_title：Biophysical journal

authors： Suever JD,Chen Y,McDonald JM,Song Y

更新日期：2008-12-15 00:00:00

abstract：:Using a model for catalysis of a dynamic equilibrium, the role of constraint in catalysis is quantified. The intrinsic rigidity of proteins is shown to be insufficient to constrain the activated complexes of enzymes, irrespective of the mechanism. However, when minimization of the surface excess free energy of water s...

journal_title：Biophysical journal

authors： Vanselow DG

更新日期：2002-05-01 00:00:00

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

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

abstract：:The general formalism required to treat two-state sliding filament models of muscle contraction, including free energy considerations, is first reviewed and amplified. This formalism is then used to examine, and modify as needed, three models studied previously by Podolsky and Nolan, in which cross-bridge attachment-d...

journal_title：Biophysical journal

authors： Hill TL,Eisenberg E,Chen YD,Podolsky RJ

更新日期：1975-04-01 00:00:00

abstract：:ATP synthase (F-ATPase) operates as an electrochemical-to-mechanical-to-chemical energy transducer with an astounding 360 degrees rotary motion of subunits epsilongammac(10-14) (rotor) against delta(alphabeta)(3)ab(2) (stator). The enzyme's torque as a function of the angular reaction coordinate in relation to ATP-syn...

journal_title：Biophysical journal

authors： Cherepanov DA,Junge W

更新日期：2001-09-01 00:00:00

abstract：:We present a simple two-parameter model for surface charge directly associated with ion channels. A spherically symmetric "charged shell" models a distribution of surface charge arrayed about the channel entrance, with a corresponding set of image charges behind the plane of the membrane. The transition between a regi...

journal_title：Biophysical journal

authors： Naranjo D,Latorre R,Cherbavaz D,McGill P,Schumaker MF

更新日期：1994-01-01 00:00:00

abstract：:Atomic force microscopy (AFM) is used to study mechanical properties of biological materials at submicron length scales. However, such samples are often structurally heterogeneous even at the local level, with different regions having distinct mechanical properties. Physical or chemical disruption can isolate individu...

journal_title：Biophysical journal

authors： Lee JJ,Rao S,Kaushik G,Azeloglu EU,Costa KD

更新日期：2018-06-05 00:00:00

abstract：:Protein splicing is an autocatalytic reaction where an intervening element (intein) is excised and the remaining two flanking sequences (exteins) are joined. The reaction requires specific conserved residues, and activity may be affected by both the intein and the extein sequence. Predicting how sequence will affect a...

journal_title：Biophysical journal

authors： Shemella PT,Topilina NI,Soga I,Pereira B,Belfort G,Belfort M,Nayak SK

更新日期：2011-05-04 00:00:00

abstract：:Gaining information about receptor profiles on cells, and subsequently finding the most efficient ligands for these signaling receptors, remain challenging tasks in stem cell and cancer research as well as drug development. We introduce a live-cell method with great potential in both screening for surface receptors an...

journal_title：Biophysical journal

authors： Wienken U,Gaub HE

更新日期：2013-12-17 00:00:00

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

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

abstract：:Two modes of behavior of single human red cells in a shear field have been described. It is known that in low viscosity media and at shear rates less than 20 s-1, the cells rotate with a periodically varying angular velocity, in accord with the theory of Jeffery (1922) for oblate spheroids. In media of viscosity great...

journal_title：Biophysical journal

authors： Bitbol M

更新日期：1986-05-01 00:00:00

abstract：:We investigate the validity of continuum electrostatics in the gramicidin A channel using a recently determined high-resolution structure. The potential and electric field acting on ions in and around the channel are computed by solving Poisson's equation. These are then used in Brownian dynamics simulations to obtain...

journal_title：Biophysical journal

authors： Edwards S,Corry B,Kuyucak S,Chung SH

更新日期：2002-09-01 00:00:00

abstract：:We have attempted to link the solution actomyosin ATPase with the mechanical properties of in vitro actin filament sliding over heavy meromyosin. To accomplish this we perturbed the system by altering the substrate with various NTPs and divalent cations, and by altering ionic strength. A wide variety of enzymatic and ...

journal_title：Biophysical journal

authors： Amitani I,Sakamoto T,Ando T

更新日期：2001-01-01 00:00:00

abstract：:Aggregated Markov models are a widely used tool to model patch clamp data measured from single ion channels. These channels must obey the principle of detailed balance in thermodynamic equilibrium; otherwise, the channel is driven by an external source of energy. We investigate the power of a likelihood ratio test for...

journal_title：Biophysical journal

authors： Wagner M,Timmer J

更新日期：2000-12-01 00:00:00

abstract：:Axonal beading, or the formation of a series of swellings along the axon, and retraction are commonly observed shape transformations that precede axonal atrophy in Alzheimer's disease, Parkinson's disease, and other neurodegenerative conditions. The mechanisms driving these morphological transformations are poorly und...

journal_title：Biophysical journal

authors： Datar A,Ameeramja J,Bhat A,Srivastava R,Mishra A,Bernal R,Prost J,Callan-Jones A,Pullarkat PA

更新日期：2019-09-03 00:00:00

abstract：:To record post synaptic potentials or electrical activity from processes of single cells in a central nervous system (CNS) preparation in situ, voltage sensitive dyes can be injected intracellularly, thereby staining only the cell under investigation. We report the structure, evaluation, and synthesis of 11 fluorescen...

journal_title：Biophysical journal

authors： Grinvald A,Salzberg BM,Lev-Ram V,Hildesheim R

更新日期：1987-04-01 00:00:00

abstract：:On the basis of its role in the analysis of mammillary compartmental systems, a matrix with non-zero elements in the first row, first column, and along the main diagonal and with zero elements elsewhere is called a mammillary matrix. It is pointed out that such matrices occur in a variety of biological problems includ...

journal_title：Biophysical journal

authors： Hearon JZ

更新日期：1964-01-01 00:00:00

abstract：:Fluorescence resonance energy transfer (FRET) was used to reveal aspects of the mechanism of signal transduction by epidermal growth factor receptors (EGFR). The superpositions of epidermal growth factor (EGF), transforming growth factor-alpha (TGFalpha) and an antibody fragment (29.1) to the carbohydrate extremity of...

journal_title：Biophysical journal

authors： Martin-Fernandez M,Clarke DT,Tobin MJ,Jones SV,Jones GR

更新日期：2002-05-01 00:00:00

abstract：:The regulated ability of integrin alphaIIbbeta3 to bind fibrinogen plays a crucial role in platelet aggregation and hemostasis. We have developed a model system based on laser tweezers, enabling us to measure specific rupture forces needed to separate single receptor-ligand complexes. First of all, we performed a thor...

journal_title：Biophysical journal

authors： Litvinov RI,Bennett JS,Weisel JW,Shuman H

更新日期：2005-10-01 00:00:00

abstract：:As double-stranded DNA is stretched to its B-form contour length, models of polymer elasticity can describe the dramatic increase in measured force. When the molecule is stretched beyond this contour length, it shows a highly cooperative overstretching transition. We have measured the elasticity and overstretching tra...

journal_title：Biophysical journal

authors： Wenner JR,Williams MC,Rouzina I,Bloomfield VA

更新日期：2002-06-01 00:00:00

abstract：:We developed a kinetic model for a single-substrate trimolecular enzymatic system, where a receptor binds and stretches a substrate to expose its cleavage site, allowing an enzyme to bind and cleave it into product. We demonstrated that the general kinetics of the trimolecular enzymatic system is more complex than the...

journal_title：Biophysical journal

authors： Chen W,Zhu C

更新日期：2010-05-19 00:00:00

abstract：:Despite the recognition that actin filaments are important for numerous cellular processes, and decades of investigation, the dynamics of in vitro actin filaments are still not completely understood. Here, we follow the time evolution of the length distribution of labeled actin reporter filaments in an unlabeled F-act...

journal_title：Biophysical journal

authors： Schmoller KM,Niedermayer T,Zensen C,Wurm C,Bausch AR

更新日期：2011-08-17 00:00:00

abstract：:The functional organization of prokaryotic cell membranes, which is essential for many cellular processes, has been challenging to analyze due to the small size and nonflat geometry of bacterial cells. Here, we use single-molecule fluorescence microscopy and three-dimensional quantitative analyses in live Escherichia ...

journal_title：Biophysical journal

authors： Oswald F,Varadarajan A,Lill H,Peterman EJ,Bollen YJ

更新日期：2016-03-08 00:00:00

abstract：:Genomics is a sequence-based informatics science and a three-dimensional-structure-based material science. However, in practice, most genomics researchers utilize sequence-based informatics approaches or three-dimensional-structure-based material science techniques, not both. This division is, at least in part, the re...

journal_title：Biophysical journal

authors： Li Z,Sun R,Bishop TC

更新日期：2020-05-05 00:00:00