Abstract:
:A lattice relaxation algorithm is developed to solve the Poisson-Nernst-Planck (PNP) equations for ion transport through arbitrary three-dimensional volumes. Calculations of systems characterized by simple parallel plate and cylindrical pore geometries are presented in order to calibrate the accuracy of the method. A study of ion transport through gramicidin A dimer is carried out within this PNP framework. Good agreement with experimental measurements is obtained. Strengths and weaknesses of the PNP approach are discussed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Kurnikova MG,Coalson RD,Graf P,Nitzan Adoi
10.1016/S0006-3495(99)77232-2subject
Has Abstractpub_date
1999-02-01 00:00:00pages
642-56issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(99)77232-2journal_volume
76pub_type
杂志文章abstract::Diphtheria toxin (DT) contains separate domains for receptor-specific binding, translocation, and enzymatic activity. After binding to cells, DT is taken up into endosome-like acidic compartments where the translocation domain inserts into the endosomal membrane and releases the catalytic domain into the cytosol. The ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.113498
更新日期:2008-03-15 00:00:00
abstract::The effect of weak, nonspecific interaction between molecules confined within restricted elements of volume ("pores") and the boundary surfaces of the pore, upon the reactivity and physical state of the confined molecules, is explored by means of simple models. A confined molecule is represented by a rectangular paral...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80304-8
更新日期:1995-04-01 00:00:00
abstract::The retinal Na+:Ca2+, K+exchanger cDNA was transiently expressed in human embryonic kidney (HEK 293) cells by transfection with plasmid DNA. The correct targeting of the expressed protein to the plasma membrane was confirmed by immunocytochemistry. The reverse exchange offrent (Ca2+ imported per Na+ extruded) was meas...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78046-9
更新日期:1997-07-01 00:00:00
abstract::Rhodobacter sphaeroides can swim toward a wide range of attractants (a process known as taxis), propelled by a single rotating flagellum. The reversals of motor direction that cause tumbles in Eschericia coli taxis are replaced by brief motor stops, and taxis is controlled by a complex sensory system with multiple hom...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76678-1
更新日期:2000-03-01 00:00:00
abstract::The aggregation of amyloid-β (Aβ) peptides plays a crucial role in the etiology of Alzheimer's disease (AD). Recently, it has been reported that an A2T mutation in Aβ can protect against AD. Interestingly, a nonpolar A2V mutation also has been found to offer protection against AD in the heterozygous state, although it...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2014.12.013
更新日期:2015-02-03 00:00:00
abstract::Laurdan fluorescence, novel spectral fitting, and dynamic light scattering were combined to determine lateral lipid organization in mixed lipid membranes of the oxidized lipid, 1-palmitoyl-2-glutaryl-sn-glycero-3-phosphocholine (PGPC), and each of the three bilayer lipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.03.009
更新日期:2020-04-21 00:00:00
abstract::Nuclear transport receptors (NTRs) mediate nucleocytoplasmic transport via their affinity for unstructured proteins (polymers) in the nuclear pore complex (NPC). Here, we have modeled the effect of NTRs on polymeric structure in the nanopore confinement of the NPC central conduit. The model explicitly takes into accou...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.11.013
更新日期:2013-12-17 00:00:00
abstract::Two mechanisms for the interaction of alternating electrical fields with biological tissue are the development of heat, via i(2)R losses, and field-induced force effects, via differences in passive electrical properties. It has been shown that for continuous wave (CW) fields in media of physiologic electrical conducti...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(70)86346-9
更新日期:1970-10-01 00:00:00
abstract::The mechanical properties of cross-linked microtubule bundles were measured from outer pillar cells isolated from the mammalian inner ear. Measurements were made using a three-point bending test and were incorporated into a mathematical model designed to distinguish between the stiffness contributions from microtubule...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78255-9
更新日期:1997-10-01 00:00:00
abstract::O-acetylserine sulfhydrylase, a homo-dimeric enzyme from Salmonella typhimurium, covalently binds one pyridoxal 5'-phosphate molecule per subunit as a fluorescent coenzyme. Different tautomers of the Schiff base between the coenzyme and lysine 41 generate structured absorption and fluorescence spectra upon one-photon ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76167-X
更新日期:2001-04-01 00:00:00
abstract::Structural rearrangements of the myosin upper-50 kD subdomain are thought to play a key role in coordinating actin binding with nucleotide hydrolysis during the myosin ATPase cycle. Such rearrangements could open and close the active site in opposition to the actin-binding cleft, helping explain the opposing affinitie...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.059840
更新日期:2005-09-01 00:00:00
abstract::Bovine brain phosphatidylserine (BBPS) vesicles were prepared with traces of dioleoylglycerol (18:1, 18:1 DAG) or hexadecane (HD) to determine the influence of changes in headgroup or acyl chain packing on divalent cation-induced lipid mixing rates. A stopped-flow apparatus was used to combine vesicles with 3 mM Ca2+ ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(94)80786-6
更新日期:1994-02-01 00:00:00
abstract::The accurate prediction of membrane-insertion probability for arbitrary protein sequences is a critical challenge to identifying membrane proteins and determining their folded structures. Although algorithms based on sequence statistics have had moderate success, a complete understanding of the energetic factors that ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.01.021
更新日期:2012-02-22 00:00:00
abstract::Structural changes in frog skeletal muscle were studied using x-ray diffraction with a time resolution of 0.53-1.02 ms after a single electrical stimulus at 8 degrees C. Tension began to drop at 6 ms (latency relaxation), reached a minimum at 8 ms, and then twitch tension developed. The intensity of the meridional ref...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74925-X
更新日期:2003-02-01 00:00:00
abstract::Enterococcus hirae V1-ATPase is a molecular motor composed of the A3B3 hexamer ring and the central stalk. In association with ATP hydrolysis, three catalytic AB pairs in the A3B3 ring undergo conformational changes, which lead to a 120° rotation of the central stalk. To understand how the conformational changes of th...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.01.029
更新日期:2017-03-14 00:00:00
abstract::Observation of cell membrane buckling and cell folding in micropipette aspiration experiments was used to evaluate the bending rigidity of the red blood cell membrane. The suction pressure required to buckle the membrane surface initially was found to be about one-half to two-thirds of the pressure that caused the cel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84319-7
更新日期:1983-07-01 00:00:00
abstract::Large bottlebrush complexes formed from the polysaccharide hyaluronan (HA) and the proteoglycan aggrecan contribute to cartilage compression resistance and are necessary for healthy joint function. A variety of mechanical forces act on these complexes in the cartilage extracellular matrix, motivating the need for a qu...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.08.016
更新日期:2020-10-06 00:00:00
abstract::The intracellular and interstitial potentials associated with each cell or fiber in multicellular preparations carrying a uniformly propagating wave are important for characterizing the electrophysiological behavior of the preparation and in particular, for evaluating the source contributed by each fiber. The aforemen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(88)83172-2
更新日期:1988-06-01 00:00:00
abstract::This study reports the solid-state NMR spectroscopic characterization of the amino-proximate transmembrane domain (TM-A) of a diverged microsomal delta12-desaturase (CREP-1) in a phospholipid bilayer. A series of TM-A peptides were synthesized with 2H-labeled side chains (Ala-53, -56, and -63, Leu-62, Val-50), and the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.067884
更新日期:2006-02-15 00:00:00
abstract::An analytical electromechanical model of a spherical cell exposed to an alternating electric field was used to calculate shear stress generated in the cellular membrane. Shape deformation of Neurospora crassa (slime) spheroplasts was measured. Statistical analysis permitted empirical evaluation of creep of the cellula...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81866-0
更新日期:1992-03-01 00:00:00
abstract::Using both quasi-elastic light scattering spectroscopy and angular dissymmetry in the intensity of the scattered light, we examined the onset of turbidity for intact calf lenses and for isolated nuclear cytoplasm. In the case of the nuclear cytoplasm these measurements demonstrate the presence of two kinds of scattere...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:
更新日期:1982-03-01 00:00:00
abstract::Understanding how polypeptides can efficiently and reproducibly attain a self-entangled conformation is a compelling biophysical challenge that might shed new light on our general knowledge of protein folding. Complex lassos, namely self-entangled protein structures characterized by a covalent loop sealed by a cystein...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.05.025
更新日期:2019-07-23 00:00:00
abstract::Under the assumption that vesicles are the anatomic correlate of quantal release, the forces governing the movement of synaptic vesicles inside neurons are analyzed. Semiquantitative calculations are presented to show that a diffuse layer field penetrates a few Debye lengths into the axoplasm. This field binds tightly...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(73)85973-9
更新日期:1973-02-01 00:00:00
abstract::The solution-scattering profiles of macromolecules are significantly affected by the thermal motions of their atoms, especially at wide scattering angles, even when only a single conformational state is significantly populated in solution. Here it is shown that the impact thermal motions have on the molecular componen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2014.02.016
更新日期:2014-04-01 00:00:00
abstract::Nonlinear optical Stokes ellipsometric (NOSE) microscopy was demonstrated for the analysis of collagen-rich biological tissues. NOSE is based on polarization-dependent second harmonic generation imaging. NOSE was used to access the molecular-level distribution of collagen fibril orientation relative to the local fiber...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.05.055
更新日期:2016-10-04 00:00:00
abstract::The yolk granule is the most abundant membrane-bound organelle present in sea urchin eggs and embryos. The major protein component of this organelle, toposome, accounts for approximately 50% of the total yolk protein and has been shown to be localized to the embryonic cell surface. Extensive characterization in severa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.089979
更新日期:2006-12-15 00:00:00
abstract::We have established a quantum mechanics (QM)/molecular mechanics (MM) hybrid method for calculating the Raman spectra of protein-bound cofactors using the alpha-subunit of C-phycocyanin containing a phycocyanobilin (PCB) chromophore as a test case. The PCB cofactor was described with density functional theory, whereas...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.108878
更新日期:2007-09-15 00:00:00
abstract::In dialyzed Myxicola axons substitution of heavy water (D2O) externally and internally slows both sodium and potassium kinetics and decreases the maximum conductances. Furthermore, this effect is strongly temperature dependent, the magnitude of the slowing produced by D2O substitution decreasing with increasing temper...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(79)85211-X
更新日期:1979-08-01 00:00:00
abstract::In high light conditions, cyanobacteria dissipate excess absorbed energy as heat in the light-harvesting phycobilisomes (PBs) to protect the photosynthetic system against photodamage. This process requires the binding of the red active form of the Orange Carotenoid Protein (OCP(r)), which can effectively quench the ex...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.03.008
更新日期:2012-04-04 00:00:00
abstract::The photocycle of the photophobic receptor from Natronobacterium pharaonis, NpSRII, is studied by static and time-resolved step-scan Fourier transform infrared spectroscopy. Both low-temperature static and time-resolved spectra resolve a K-like intermediate, and the corresponding spectra show little difference within ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74935-2
更新日期:2003-02-01 00:00:00