Abstract:
:This paper examines "realistic" pores, i.e., ones that are neither symmetric nor of uniform diameter. Methods are described that permit estimation of the image potential for an ion in an aqueous pore spanning a lipid membrane and for the electric field produced in such a pore when a transmembrane potential is applied. They are used to model features of the delayed rectifier potassium channel. Constraints on the geometry of the exterior mouth, the dielectric properties of the narrow part of the pore and the conduction mechanism are determined for this channel.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Jordan PCdoi
10.1016/s0006-3495(84)84258-7subject
Has Abstractpub_date
1984-06-01 00:00:00pages
1101-7issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(84)84258-7journal_volume
45pub_type
杂志文章abstract::A recipe is given for designing theoretical models for donor-acceptor systems in which fluorescence energy transfer and motion takes place simultaneously. This recipe is based on the idea that a system exhibiting both motion and fluorescence energy transfer can be modeled by specifying a number of "states" and the rat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81490-5
更新日期:1993-04-01 00:00:00
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
更新日期:2009-11-18 00:00:00
abstract::The structure of polyamines-DNA precipitates was studied by x-ray diffraction. Precise measurements of the interhelix distance a(H) were obtained at different NaCl, polyamine, and DNA concentrations. Most of the results were obtained using spermine and few others using spermidine. The precipitates are liquid crystalli...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.040113
更新日期:2005-01-01 00:00:00
abstract::We revisit a heteropolymer collapse theory originally introduced to explore how the balance between hydrophobic interactions and configurational entropy determines the thermal stability of globular proteins at ambient pressure. We generalize the theory by introducing a basic statistical mechanical treatment for how pr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.081802
更新日期:2006-10-01 00:00:00
abstract::A dynamic model of smooth muscle contraction is presented and is compared with the mechanical properties of vascular smooth muscle in the rat portal vein. The model is based on the sliding filament theory and the assumption that force is produced by cross-bridges extending from the myosin to the actin filaments. Thus,...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(86)83448-8
更新日期:1986-07-01 00:00:00
abstract::Fiber orientation and ventricular geometry are incorporated in a mathematical model for ejection fraction of the human left ventricle. The inadequacy of circularly oriented or "constrictor" fibers to explain high ejection fractions of cylindrical, spherical, or ellipsoidal reference ventricles is demonstrated. A class...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(69)86429-5
更新日期:1969-07-01 00:00:00
abstract::Previous mathematical modeling of beta cell electrical activity has involved single cells or, recently, clusters of identical cells. Here we model clusters of heterogeneous cells that differ in size, channel density, and other parameters. We use gap-junctional electrical coupling, with conductances determined by an ex...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81539-X
更新日期:1993-06-01 00:00:00
abstract::Moesin, a protein of the ezrin, radixin, and moesin family, which links the plasma membrane to the cytoskeleton, is involved in multiple physiological and pathological processes, including viral budding and infection. Its interaction with the plasma membrane occurs via a key phosphoinositide, the phosphatidyl(4,5)inos...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.10.041
更新日期:2018-01-09 00:00:00
abstract::Cholesterol is essential to the formation of phase-separated lipid domains in membranes. Lipid domains can exist in different thermodynamic phases depending on the molecular composition and play significant roles in determining structure and function of membrane proteins. We investigate the role of cholesterol in the ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.10.011
更新日期:2018-12-04 00:00:00
abstract::We study the stochastic dynamics of growth and shrinkage of single actin filaments taking into account insertion, removal, and ATP hydrolysis of subunits either according to the vectorial mechanism or to the random mechanism. In a previous work, we developed a model for a single actin or microtubule filament where hyd...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.12.4306
更新日期:2010-04-21 00:00:00
abstract::We investigate lateral organization of lipid domains in vesicles versus supported membranes and monolayers. The lipid mixtures used are predominantly DOPC/DPPC/Chol and DOPC/BSM/Chol, which have been previously shown to produce coexisting liquid phases in vesicles and monolayers. In a monolayer at an air-water interfa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74345-3
更新日期:2004-05-01 00:00:00
abstract::Molecular chaperone Hsp70 plays important roles in the pathology of amyloid diseases by inhibiting aberrant aggregation of proteins. However, the biophysical mechanism of the interaction of Hsp70 with the intrinsically disordered proteins (IDPs) is unclear. Here, we report that Hsp70 inhibits aggregation of islet amyl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.12.019
更新日期:2021-01-06 00:00:00
abstract::The binding mechanism of sweet proteins to their receptor, a G-protein-coupled receptor, is not supported by direct structural information. In principle, the key groups responsible for biological activity (glucophores) can be localized on a small structural unit (sweet finger) or spread on a larger surface area. A rec...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.073171
更新日期:2006-05-01 00:00:00
abstract::A 10-ns molecular dynamics simulation of mouse acetylcholinesterase was analyzed, with special attention paid to the fluctuation in the width of the gorge and opening events of the back door. The trajectory was first verified to ensure its stability. We defined the gorge proper radius as the measure for the extent of ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75736-0
更新日期:2001-08-01 00:00:00
abstract::Red blood cell membrane exhibits a large resistance to changes in surface area. This resistance is characterized by the area expansivity modulus K, which relates the isotropic membrane force resultant, T, to the fractional change in membrane surface area delta A/Ao. The experimental technique commonly used to determin...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82607-2
更新日期:1990-04-01 00:00:00
abstract::Here it is reported that aggrecan, the highly negatively charged macromolecule in the cartilage extracellular matrix, undergoes Ca(2+)-mediated self-adhesion after static compression even in the presence of strong electrostatic repulsion in physiological-like solution conditions. Aggrecan was chemically end-attached o...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.128389
更新日期:2008-11-15 00:00:00
abstract::Actin polymerization is typically initiated at specific sites in a cell by membrane-bound protein complexes, and the resulting structures are involved in specialized cellular functions, such as migration, particle uptake, or mitotic division. Here we analyze the potential of the actin system to self-organize into wave...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2008.12.3942
更新日期:2009-04-08 00:00:00
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
更新日期:1994-05-01 00:00:00
abstract::mRNAs are involved in complicated supramolecular complexes with human 40S and 80S ribosomes responsible for the protein synthesis. In this work, a derivative of nonaribonucleotide pUUCGUAAAA with nitroxide spin labels attached to the 5'-phosphate and to the C8 atom of the adenosine in sixth position (mRNA analog) was ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.10.042
更新日期:2015-12-15 00:00:00
abstract::Filopodia perform cellular functions such as environmental sensing or cell motility, but they also grab for particles and withdraw them leading to an increased efficiency of phagocytic uptake. Remarkably, withdrawal of micron-sized particles is also possible without noticeable movements of the filopodia. Here, we demo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.02.029
更新日期:2015-05-05 00:00:00
abstract::We performed pressure-tuning hole-burning experiments on a modified cytochrome c protein in a glycerol/buffer glass. The shift and the broadening of the holes were investigated for various frequencies within the inhomogeneous band. On the basis of a simple model, we were able to estimate the interaction range between ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74124-7
更新日期:2004-01-01 00:00:00
abstract::Fusion is a crucial event in the infection of animal cells by enveloped viruses (e.g., HIV or influenza). Viral fusion is mediated by glycoproteins, spanning the viral envelope, which attach to a membrane surface and induce fusion of the viral envelope to the cellular membrane. Influenza fusion protein (hemagglutinin)...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78175-X
更新日期:1997-09-01 00:00:00
abstract::Recent NMR structural characterization studies showed that a seven-residue segment (FKKGERL) from the src SH3 domain adopts the nativelike diverging type II beta-turn in aqueous solution in support of the prediction based on the I-sites library of sequence structural motifs. We study the conformational variability and...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74966-2
更新日期:2003-03-01 00:00:00
abstract::Hydrophobic interactions between a bilayer and its embedded membrane proteins couple protein conformational changes to changes in the packing of the surrounding lipids. The energetic cost of a protein conformational change therefore includes a contribution from the associated bilayer deformation energy (DeltaGdef0), w...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77252-8
更新日期:1999-02-01 00:00:00
abstract::The bovine eye lens protein, alpha L crystallin, has been studied with photon correlation spectroscopy and statical light scattering in the concentration range up to 200 g/l in different solvent conditions. At higher concentration (c greater than 70 g/l) the scattering behavior is quite complicated, which results in n...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83955-2
更新日期:1985-05-01 00:00:00
abstract::Mislocalization and aggregation of the huntingtin protein are related to Huntington's disease. Its first exon-more specifically the first 17 amino acids (Htt17)-is crucial for the physiological and pathological functions of huntingtin. It regulates huntingtin's activity through posttranslational modifications and serv...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.02.001
更新日期:2015-03-10 00:00:00
abstract::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 Prot...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.01.027
更新日期:2013-03-05 00:00:00
abstract::To assess if membrane diffusion could affect the kinetics of receptor recruitment at adhesive contacts, we transfected neurons with green fluorescent protein-tagged immunoglobin cell adhesion molecules of varying length (25-180 kD), and measured the lateral mobility of single quantum dots bound to those receptors at t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.071688
更新日期:2005-11-01 00:00:00
abstract::We apply fluorescence lifetime imaging to the membrane phase-sensing dye di-4-ANEPPDHQ in model membranes and live cells. We show that the 1700 ps lifetime shift between liquid-disordered and liquid-ordered phases offers greater contrast than the 60 nm spectral shift previously reported. Detection of cholesterol-rich ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.084673
更新日期:2006-06-01 00:00:00
abstract::Specific proteins and lipids sequester to regions of cell membranes called rafts. Due to their high content of sphingomyelin (SM) and cholesterol, raft bilayers are thicker than nonraft bilayers and, at least at 4 degrees C, are resistant to Triton X-100 extraction. It has been postulated that rafts concentrate protei...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74595-0
更新日期:2003-09-01 00:00:00