The pH-induced release of iron from transferrin investigated with a continuum electrostatic model.

Abstract:

:A reduction in pH induces the release of iron from transferrin in a process that involves a conformational change in the protein from a closed to an open form. Experimental evidence suggests that there must be changes in the protonation states of certain, as yet not clearly identified, residues in the protein accompanying this conformational change. Such changes in protonation states of residues and the consequent changes in electrostatic interactions are assumed to play a large part in the mechanism of release of iron from transferrin. Using the x-ray crystal structures of human ferri- and apo-lactoferrin, we calculated the pKa values of the titratable residues in both the closed (iron-loaded) and open (iron-free) conformations with a continuum electrostatic model. With the knowledge of a residue's pKa value, its most probable protonation state at any specified pH may be determined. The preliminary results presented here are in good agreement with the experimental observation that the binding of ferric iron and the synergistic anion bicarbonate/carbonate results in the release of approximately three H+ ions. It is suggested that the release of these three H+ ions may be accounted for, in most part, by the deprotonation of the bicarbonate and residues Tyr-92, Lys-243, Lys-282, and Lys-285 together with the protonation of residues Asp-217 and Lys-277.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Lee DA,Goodfellow JM

doi

10.1016/S0006-3495(98)77983-4

subject

Has Abstract

pub_date

1998-06-01 00:00:00

pages

2747-59

issue

6

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(98)77983-4

journal_volume

74

pub_type

杂志文章
  • THE ARRANGEMENTS OF NUCLEOTIDE SEQUENCES IN T2 AND T5 BACTERIOPHAGE DNA MOLECULES.

    abstract::The genetic map of T4 (and T2) bacteriophage is circular but the DNA molecule that is liberated by phenol extraction is a linear duplex of polynucleotide chains. If the genetic map is related to the physical structure of the DNA molecule, the problem arises as to how a linear molecule can give rise to a circular map. ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/s0006-3495(64)86771-0

    authors: THOMAS CA Jr,RUBENSTEIN I

    更新日期:1964-03-01 00:00:00

  • Study of anisotropy in nuclear magnetic resonance relaxation times of water protons in skeletal muscle.

    abstract::The anisotropy of the spin-lattice relaxation time (T1) and the spin-spin relaxation times (T2) of water protons in skeletal muscle tissue have been studied by the spin-echo technique. Both T1 and T2 have been measured for the water protons of the tibialis anterior muscle of mature male rats for theta = 0, 55, and 90 ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(80)85102-2

    authors: Kasturi SR,Chang DC,Hazlewood CF

    更新日期:1980-06-01 00:00:00

  • Use of protein database for the computation of the dipole moments of normal and abnormal hemoglobins.

    abstract::Previously, we discussed the calculation of the dipole moments of small proteins using the three-dimensional protein data-base. Our results demonstrate that the calculated dipole moments are in acceptable agreement with measured values. We, however, noted the difficulty of the calculation with larger proteins, in part...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(93)81524-8

    authors: Takashima S

    更新日期:1993-05-01 00:00:00

  • Destabilizing the AXH Tetramer by Mutations: Mechanisms and Potential Antiaggregation Strategies.

    abstract::The AXH domain of protein Ataxin 1 is thought to play a key role in the misfolding and aggregation pathway responsible for Spinocerebellar ataxia 1. For this reason, a molecular level understanding of AXH oligomerization pathway is crucial to elucidate the aggregation mechanism, which is thought to trigger the disease...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2017.11.025

    authors: Grasso G,Morbiducci U,Massai D,Tuszynski JA,Danani A,Deriu MA

    更新日期:2018-01-23 00:00:00

  • Model for Bundling of Keratin Intermediate Filaments.

    abstract::Keratin intermediate filaments form dynamic intracellular networks, which span the entire cytoplasm and provide mechanical strength to the cell. The mechanical resilience of the keratin intermediate filament network itself is determined by filament bundling. The bundling process can be reproduced in artificial conditi...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2020.05.024

    authors: Haimov E,Windoffer R,Leube RE,Urbakh M,Kozlov MM

    更新日期:2020-07-07 00:00:00

  • Measuring the Refractive Index of Bovine Corneal Stromal Cells Using Quantitative Phase Imaging.

    abstract::The cornea is the primary refractive lens in the eye and transmits >90% of incident visible light. It has been suggested that the development of postoperative corneal haze could be due to an increase in light scattering from activated corneal stromal cells. Quiescent keratocytes are thought to produce crystallins that...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2015.08.046

    authors: Gardner SJ,White N,Albon J,Knupp C,Kamma-Lorger CS,Meek KM

    更新日期:2015-10-20 00:00:00

  • Solid phase DNA amplification: a Brownian dynamics study of crowding effects.

    abstract::Solid phase amplification (SPA), a new method to amplify DNA, is characterized by the use of surface-bound primers. This limits the amplification to two-dimensional surfaces and therefore allows the easy parallelization of DNA amplification in a single system. SPA leads to the formation of small but dense DNA brushes,...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.104.051904

    authors: Mercier JF,Slater GW

    更新日期:2005-07-01 00:00:00

  • The first extracellular loop domain is a major determinant of charge selectivity in connexin46 channels.

    abstract::Intercellular channels formed of members of the gene family of connexins (Cxs) vary from being substantially cation selective to being anion selective. We took advantage of the ability of Cx46 to function as an unopposed hemichannel to examine the basis of Cx charge selectivity. Previously we showed Cx46 hemichannels ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(00)76539-8

    authors: Trexler EB,Bukauskas FF,Kronengold J,Bargiello TA,Verselis VK

    更新日期:2000-12-01 00:00:00

  • Quantifying Instrumental Artifacts in Folding Kinetics Measured by Single-Molecule Force Spectroscopy.

    abstract::Force spectroscopy is commonly used to measure the kinetics of processes occurring in single biological molecules. These measurements involve attaching the molecule of interest to micron-sized or larger force probes via compliant linkers. Recent theoretical work has described how the properties of the probes and linke...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.06.011

    authors: Neupane K,Woodside MT

    更新日期:2016-07-26 00:00:00

  • Behavior of supercoiled DNA.

    abstract::We study DNA supercoiling in a quantitative fashion by micromanipulating single linear DNA molecules with a magnetic field gradient. By anchoring one end of the DNA to multiple sites on a magnetic bead and the other end to multiple sites on a glass surface, we were able to exert torsional control on the DNA. A rotatin...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(98)77908-1

    authors: Strick TR,Allemand JF,Bensimon D,Croquette V

    更新日期:1998-04-01 00:00:00

  • Redox Modulation of Oligomeric State in Proline Utilization A.

    abstract::Homooligomerization of proline utilization A (PutA) bifunctional flavoenzymes is intimately tied to catalytic function and substrate channeling. PutA from Bradyrhizobium japonicum (BjPutA) is unique among PutAs in that it forms a tetramer in solution. Curiously, a dimeric BjPutA hot spot mutant was previously shown to...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2018.04.046

    authors: Korasick DA,Campbell AC,Christgen SL,Chakravarthy S,White TA,Becker DF,Tanner JJ

    更新日期:2018-06-19 00:00:00

  • Conformations of an adenine bulge in a DNA octamer and its influence on DNA structure from molecular dynamics simulations.

    abstract::Molecular dynamics simulations have been applied to the DNA octamer d(GCGCA-GAAC). d(GTTCGCGC), which has an adenine bulge at the center to determine the pathway for interconversion between the stacked and extended forms. These forms are known to be important in the molecular recognition of bulges. From a total of ~35...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(01)75705-0

    authors: Feig M,Zacharias M,Pettitt BM

    更新日期:2001-07-01 00:00:00

  • Oxygen permeability of the limiting layers of the cornea.

    abstract::Using polarography and suitable mathematical analysis, the oxygen permeability of an individual layer of a bilayered tissue may be determined if the oxygen consumption and permeability of the other layer are known. Results obtained on rabbit cornea indicate that the permeability of the epithelium is about four times t...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(72)86083-1

    authors: Freeman RD,Fatt I

    更新日期:1972-03-01 00:00:00

  • Lanthanides Report Calcium Sensor in the Vestibule of Ryanodine Receptor.

    abstract::Ca2+ regulates ryanodine receptor's (RyR) activity through an activating and an inhibiting Ca2+-binding site located on the cytoplasmic side of the RyR channel. Their altered sensitivity plays an important role in the pathology of malignant hyperthermia and heart failure. We used lanthanide ions (Ln3+) as probes to in...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2017.03.023

    authors: Sárközi S,Komáromi I,Jóna I,Almássy J

    更新日期:2017-05-23 00:00:00

  • Microrheology for Hi-C Data Reveals the Spectrum of the Dynamic 3D Genome Organization.

    abstract::The one-dimensional information of genomic DNA is hierarchically packed inside the eukaryotic cell nucleus and organized in a three-dimensional (3D) space. Genome-wide chromosome conformation capture (Hi-C) methods have uncovered the 3D genome organization and revealed multiscale chromatin domains of compartments and ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2020.02.020

    authors: Shinkai S,Sugawara T,Miura H,Hiratani I,Onami S

    更新日期:2020-05-05 00:00:00

  • The association of polar residues in the DAP12 homodimer: TOXCAT and molecular dynamics simulation studies.

    abstract::Dimerization of the transmembrane (TM) adaptor protein DAP12 plays a key role in mediating activation signals through TM-TM association with cell-surface receptors. Herein, we apply the TOXCAT assay and molecular dynamics simulation to analyze dynamics and dimerization of the TM helix of DAP12 in the membrane bilayer....

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2013.01.054

    authors: Wei P,Zheng BK,Guo PR,Kawakami T,Luo SZ

    更新日期:2013-04-02 00:00:00

  • Voltage-dependent hydration and conduction properties of the hydrophobic pore of the mechanosensitive channel of small conductance.

    abstract::A detailed picture of water and ion properties in small pores is important for understanding the behavior of biological ion channels. Several recent modeling studies have shown that small, hydrophobic pores exclude water and ions even if they are physically large enough to accommodate them, a mechanism called hydropho...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.080432

    authors: Spronk SA,Elmore DE,Dougherty DA

    更新日期:2006-05-15 00:00:00

  • Molecular distances from dipolar coupled spin-labels: the global analysis of multifrequency continuous wave electron paramagnetic resonance data.

    abstract::For immobilized nitroxide spin-labels with a well-defined interprobe geometry, resolved dipolar splittings can be observed in continuous wave electron paramagnetic resonance (CW-EPR) spectra for interelectron distances as large as 30 A using perdeuterated probes. In this work, algorithms are developed for calculating ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(97)78832-5

    authors: Hustedt EJ,Smirnov AI,Laub CF,Cobb CE,Beth AH

    更新日期:1997-04-01 00:00:00

  • Inferring the cellular origin of voltage and calcium alternans from the spatial scales of phase reversal during discordant alternans.

    abstract::Beat-to-beat alternation of the action potential duration (APD) in paced cardiac cells has been linked to the onset of lethal arrhythmias. Both experimental and theoretical studies have shown that alternans at the single cell level can be caused by unstable membrane voltage (V(m)) dynamics linked to steep APD-restitut...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.106.100982

    authors: Sato D,Shiferaw Y,Qu Z,Garfinkel A,Weiss JN,Karma A

    更新日期:2007-02-15 00:00:00

  • Antagonistic effects of cofilin, beryllium fluoride complex, and phalloidin on subdomain 2 and nucleotide-binding cleft in F-actin.

    abstract::Cofilin/ADF, beryllium fluoride complex (BeFx), and phalloidin have opposing effects on actin filament structure and dynamics. Cofilin/ADF decreases the stability of F-actin by enhancing disorder in subdomain 2, and by severing and accelerating the depolymerization of the filament. BeFx and phalloidin stabilize the su...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.106.087767

    authors: Muhlrad A,Ringel I,Pavlov D,Peyser YM,Reisler E

    更新日期:2006-12-15 00:00:00

  • Low frequency sounds from sustained contraction of human skeletal muscle.

    abstract::Low frequency audible vibrations are produced by human skeletal muscles undergoing sustained contraction. The effect is easily demonstrable with an electronic stethoscope which amplifies sound below 50 Hz. Autocorrelation analysis of the signal shows that it is periodic with a frequency 25 +/- 2.5 Hz. The quality of t...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(80)85080-6

    authors: Oster G,Jaffe JS

    更新日期:1980-04-01 00:00:00

  • Direct Observation of the Intrinsic Backbone Torsional Mobility of Disordered Proteins.

    abstract::The fundamental backbone dynamics of unfolded proteins arising due to intrinsic ϕ-ψ dihedral angle fluctuations dictate the course of protein folding, binding, assembly, and function. These internal fluctuations are also critical for protein misfolding associated with a range of human diseases. However, direct observa...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.07.023

    authors: Jain N,Narang D,Bhasne K,Dalal V,Arya S,Bhattacharya M,Mukhopadhyay S

    更新日期:2016-08-23 00:00:00

  • Orientation and dynamics of synthetic transbilayer polypeptides containing GpATM dimerization motifs.

    abstract::Deuterium NMR spectroscopy was used to study how the positioning of a dimerization motif within a transbilayer polypeptide influences its orientation and dynamics in bilayers. Three polypeptide variants comprising glycophorin A transmembrane (GpATM) dimerization motifs incorporated into lysine-terminated poly-leucine-...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2010.12.3725

    authors: McDonald MC,Booth V,Morrow MR

    更新日期:2011-02-02 00:00:00

  • Potassium ion accumulation at the external surface of the nodal membrane in frog myelinated fibers.

    abstract::Potassium accumulation associated with outward membrane potassium current was investigated experimentally in myelinated fibers and analyzed in terms of two models-three-compartment and diffusion in an unstirred layer. In the myelinated fibers, as in squid giant axons, the three-compartment model satisfactorily describ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(80)85028-4

    authors: Moran N,Palti Y,Levitan E,Stämpfli R

    更新日期:1980-12-01 00:00:00

  • Subdiffraction-limit two-photon fluorescence microscopy for GFP-tagged cell imaging.

    abstract::We report applications of two-photon excitation fluorescence (2PEF) microscopy with subdiffraction-limit resolution for green-fluorescent-protein-tagged cell imaging. The microscope integrates 2PEF microscopy and stimulated emission depletion microscopy in one microscope that has the benefits of both techniques: intri...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2009.09.038

    authors: Li Q,Wu SS,Chou KC

    更新日期:2009-12-16 00:00:00

  • Transition states in protein folding kinetics: modeling phi-values of small beta-sheet proteins.

    abstract::Small single-domain proteins often exhibit only a single free-energy barrier, or transition state, between the denatured and the native state. The folding kinetics of these proteins is usually explored via mutational analysis. A central question is which structural information on the transition state can be derived fr...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.107.109868

    authors: Weikl TR

    更新日期:2008-02-01 00:00:00

  • Molecular motions within the pore of voltage-dependent sodium channels.

    abstract::The pores of ion channel proteins are often modeled as static structures. In this view, selectivity reflects rigidly constrained backbone orientations. Such a picture is at variance with the generalization that biological proteins are flexible, capable of major internal motions on biologically relevant time scales. We...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(97)78096-2

    authors: Bénitah JP,Ranjan R,Yamagishi T,Janecki M,Tomaselli GF,Marban E

    更新日期:1997-08-01 00:00:00

  • Diffusion of extracellular K+ can synchronize bursting oscillations in a model islet of Langerhans.

    abstract::Electrical bursting oscillations of mammalian pancreatic beta-cells are synchronous among cells within an islet. While electrical coupling among cells via gap junctions has been demonstrated, its extent and topology are unclear. The beta-cells also share an extracellular compartment in which oscillations of K+ concent...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(93)81092-0

    authors: Stokes CL,Rinzel J

    更新日期:1993-08-01 00:00:00

  • VDAC channels mediate and gate the flow of ATP: implications for the regulation of mitochondrial function.

    abstract::The mitochondrial channel, VDAC, forms large (3 nm in diameter) aqueous pores through membranes. We measured ATP flow (using the luciferin/luciferase method) through these channels after reconstitution into planar phospholipid membranes. In the open state of VDAC, as many as 2 x 10(6) ATP molecules can flow through on...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(97)78841-6

    authors: Rostovtseva T,Colombini M

    更新日期:1997-05-01 00:00:00

  • Influence of chain ordering on the selectivity of dipalmitoylphosphatidylcholine bilayer membranes for permeant size and shape.

    abstract::The effects of lipid chain packing and permeant size and shape on permeability across lipid bilayers have been investigated in gel and liquid crystalline dipalmitoylphosphatidylcholine (DPPC) bilayers by a combined NMR line-broadening/dynamic light scattering method using seven short-chain monocarboxylic acids (formic...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(98)77711-2

    authors: Xiang TX,Anderson BD

    更新日期:1998-12-01 00:00:00