Exchange of Gramicidin between Lipid Bilayers: Implications for the Mechanism of Channel Formation.

Abstract:

:The canonical mechanism of gramicidin (gA) channel formation is transmembrane dimerization of nonconducting subunits that reside in opposite bilayer leaflets. The channels do not open and close; they appear and disappear due to subunit association and dissociation. Many different types of experiments support this monomer ↔ dimer mechanism. Recently, however, this mechanism was challenged, based on experiments with lipid vesicle-incorporated gA under conditions where vesicle fusion could be controlled. In these experiments, sustained channel activity was observed long after fusion had been terminated, which led to the proposal that gA single-channel current transitions result from closed-open transitions in long-lived bilayer-spanning dimers. This proposal is at odds with 40 years of experiments, but involves the key assumption that gA monomers do not exchange between bilayers. We tested the possibility of peptide exchange between bilayers using three different types of experiments. First, we demonstrated the exchange of gA between 1,2-dierucoyl-sn-glycero-3-phosphocholine (DC22:1PC) or 1,2-dioleoyl-sn-glycero-3-phosphocholine (DC18:1PC) lipid vesicles using a fluorescence assay for gA channel activity. Second, we added gA-free DC22:1PC vesicles to both sides of planar DC18:1PC bilayers preincubated with gA, which reduced channel activity up to 10-fold. Third, we added gA-containing DC22:1PC vesicles to one or both sides of DC18:1PC planar bilayers, which produced much higher channel activity when the gA-containing vesicles were added to both sides of the bilayer, as compared to one side only. All three types of experiments show that gA subunits can exchange between lipid bilayers. The exchange of subunits between bilayers thus is firmly established, which becomes a crucial consideration with respect to the mechanism of channel formation.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Lum K,Ingólfsson HI,Koeppe RE 2nd,Andersen OS

doi

10.1016/j.bpj.2017.08.049

subject

Has Abstract

pub_date

2017-10-17 00:00:00

pages

1757-1767

issue

8

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(17)30973-6

journal_volume

113

pub_type

杂志文章
  • Characterization of the azide-dependent bacteriorhodopsin-like photocycle of salinarum halorhodopsin.

    abstract::The photocycle of salinarum halorhodopsin was investigated in the presence of azide. The azide binds to the halorhodopsin with 150 mM binding constant in the absence of chloride and with 250 mM binding constant in the presence of 1 M chloride. We demonstrate that the azide-binding site is different from that of chlori...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(02)75521-5

    authors: Lakatos M,Groma GI,Ganea C,Lanyi JK,Váró G

    更新日期:2002-04-01 00:00:00

  • Fiber interaction in a nerve trunk.

    abstract::This paper is concerned with the nature of the transmembrane potential induced in an inactive nerve fiber lying in an impressed potential field within a nerve trunk. The impressed potential field is assumed to be produced by the synchronous activity of other fibers within the trunk; an expression for the induced trans...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(71)86214-8

    authors: Clark JW Jr,Plonsey R

    更新日期:1971-03-01 00:00:00

  • Variable symmetry in Salmonella typhimurium flagellar motors.

    abstract::Electron cryomicroscopy of rotor complexes of the Salmonella typhimurium flagellar motor, overproduced in a nonmotile Escherichia coli host, has revealed a variation in subunit symmetry of the cytoplasmic ring (C ring) module. C rings with subunit symmetries ranging from 31 to 38 were found. They formed a Gaussian dis...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(03)74877-2

    authors: Young HS,Dang H,Lai Y,DeRosier DJ,Khan S

    更新日期:2003-01-01 00:00:00

  • Solvation free energy of the peptide group: its model dependence and implications for the additive-transfer free-energy model of protein stability.

    abstract::The group-additive decomposition of the unfolding free energy of a protein in an osmolyte solution relative to that in water poses a fundamental paradox: whereas the decomposition describes the experimental results rather well, theory suggests that a group-additive decomposition of free energies is, in general, not va...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2013.08.011

    authors: Tomar DS,Asthagiri D,Weber V

    更新日期:2013-09-17 00:00:00

  • Interaction of antiinflammatory drugs with EPC liposomes: calorimetric study in a broad concentration range.

    abstract::Isothermal titration calorimetry was used to characterize and quantify the partition of indomethacin and acemetacin between the bulk aqueous phase and the membrane of egg phosphatidylcholine vesicles. Significant electrostatic effects were observed due to binding of the charged drugs to the membrane, which implied the...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(04)74170-3

    authors: Matos C,Lima JL,Reis S,Lopes A,Bastos M

    更新日期:2004-02-01 00:00:00

  • Area Compressibility Moduli of the Monolayer Leaflets of Asymmetric Bilayers from Simulations.

    abstract::Extraction from simulations of the area compressibility moduli of the monolayers in a bilayer is considered theoretically. A statistical mechanical derivation shows that the bilayer modulus is the sum of the two monolayer moduli, as is often supposed but contrary to a recent study. Seemingly plausible assumptions rega...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2019.08.016

    authors: Nagle JF

    更新日期:2019-09-17 00:00:00

  • Electrostatic coupling between retinal isomerization and the ionization state of Glu-204: a general mechanism for proton release in bacteriorhodopsin.

    abstract::The pKa values of ionizable groups that lie between the active site region of bacteriorhodopsin (bR) and the extracellular surface of the protein are reported. Glu-204 is found to have an elevated pKa in the resting state of bR, suggesting that it corresponds to the proton-releasing group in bR. Its elevated pKa is pr...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(96)79320-7

    authors: Sampogna RV,Honig B

    更新日期:1996-09-01 00:00:00

  • Comparison between whole distribution- and average-based approaches to the determination of fluorescence resonance energy transfer efficiency in ensembles of proteins in living cells.

    abstract::Current methods for analysis of data from studies of protein-protein interactions using fluorescence resonance energy transfer (FRET) emerged from several decades of research using wide-field microscopes and spectrofluorometers to measure fluorescence from individual cells or cell populations. Inherent to most measure...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2010.01.048

    authors: Singh DR,Raicu V

    更新日期:2010-05-19 00:00:00

  • DNA Nanostructures on Membranes as Tools for Synthetic Biology.

    abstract::Over the last decade, functionally designed DNA nanostructures applied to lipid membranes prompted important achievements in the fields of biophysics and synthetic biology. Taking advantage of the universal rules for self-assembly of complementary oligonucleotides, DNA has proven to be an extremely versatile biocompat...

    journal_title:Biophysical journal

    pub_type: 杂志文章,评审

    doi:10.1016/j.bpj.2016.03.015

    authors: Czogalla A,Franquelim HG,Schwille P

    更新日期:2016-04-26 00:00:00

  • Stochastic interdigitation as a toughening mechanism at the interface between tendon and bone.

    abstract::Reattachment and healing of tendon to bone poses a persistent clinical challenge and often results in poor outcomes, in part because the mechanisms that imbue the uninjured tendon-to-bone attachment with toughness are not known. One feature of typical tendon-to-bone surgical repairs is direct attachment of tendon to s...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2014.09.049

    authors: Hu Y,Birman V,Deymier-Black A,Schwartz AG,Thomopoulos S,Genin GM

    更新日期:2015-01-20 00:00:00

  • Background Suppression in Imaging Gold Nanorods through Detection of Anti-Stokes Emission.

    abstract::Metallic nanoparticles have opened the possibility of imaging, tracking, and manipulating biological samples without time limitations. Their low photoluminescence quantum yield, however, makes them hard to detect under high background conditions. In this study we show that it is possible to image gold nanorods by dete...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.10.035

    authors: Carattino A,Keizer VIP,Schaaf MJM,Orrit M

    更新日期:2016-12-06 00:00:00

  • Cell growth and division. I. A mathematical model with applications to cell volume distributions in mammalian suspension cultures.

    abstract::A mathematical model is formulated for the development of a population of cells in which the individual members may grow and divide or die. A given cell is characterized by its age and volume, and these parameters are assumed to determine the rate of volume growth and the probability per unit time of division or death...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(67)86592-5

    authors: Bell GI,Anderson EC

    更新日期:1967-07-01 00:00:00

  • Identification of the scattering elements responsible for lens opacification in cold cataracts.

    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:

    authors: Delaye M,Clark JI,Benedek GB

    更新日期:1982-03-01 00:00:00

  • Microtubule assembly of isotypically purified tubulin and its mixtures.

    abstract::Numerous isotypes of the structural protein tubulin have now been characterized in various organisms and their expression offers a plausible explanation for observed differences affecting microtubule function in vivo. While this is an attractive hypothesis, there are only a handful of studies demonstrating a direct in...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.108.132233

    authors: Rezania V,Azarenko O,Jordan MA,Bolterauer H,Ludueña RF,Huzil JT,Tuszynski JA

    更新日期:2008-08-01 00:00:00

  • Theoretical analysis of the significance of whether or not enzymes or transport systems in structured media follow Michaelis-Menten kinetics.

    abstract::Pure Michaelis-Menten enzymes have been studied (i.e., enzymes with a hyperbolic (S, V) behavior in a well-stirred solution). When such enzymes are associated with a structure in vitro, even in the simplest conceivable form (immobilization in a homogeneous gel), they can produce enzymic or transport reactions with man...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(83)84401-4

    authors: Vincent JC,Thellier M

    更新日期:1983-01-01 00:00:00

  • Gating of the mechanosensitive channel protein MscL: the interplay of membrane and protein.

    abstract::The mechanosensitive channel of large conductance (MscL) belongs to a family of transmembrane channel proteins in bacteria and functions as a safety valve that relieves the turgor pressure produced by osmotic downshock. MscL gating can be triggered solely by stretching of the membrane. This work reports an effort to u...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.107.109850

    authors: Jeon J,Voth GA

    更新日期:2008-05-01 00:00:00

  • The 3-hydroxy group and 4,5-trans double bond of sphingomyelin are essential for modulation of galactosylceramide transmembrane asymmetry.

    abstract::The structural features of SPM that control the transbilayer distribution of beta-GalCer in POPC vesicles were investigated by (13)C- and (31)P-NMR spectroscopy using lipid analogs that share physical similarities with GalCer or SPM. The SPM analogs included N-palmitoyl-4,5-dihydro-SPM, 3-deoxy-SPM, 1-alkyl-2-amidopho...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.104.057059

    authors: Malewicz B,Valiyaveettil JT,Jacob K,Byun HS,Mattjus P,Baumann WJ,Bittman R,Brown RE

    更新日期:2005-04-01 00:00:00

  • From Gene to Function: Cell-Free Electrophysiological and Optical Analysis of Ion Pumps in Nanodiscs.

    abstract::Nanodiscs that hold a lipid bilayer surrounded by a boundary of scaffold proteins have emerged as a powerful tool for membrane protein solubilization and analysis. By combining nanodiscs and cell-free expression technologies, even completely detergent-free membrane protein characterization protocols can be designed. N...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2017.03.026

    authors: Henrich E,Sörmann J,Eberhardt P,Peetz O,Mezhyrova J,Morgner N,Fendler K,Dötsch V,Wachtveitl J,Bernhard F,Bamann C

    更新日期:2017-09-19 00:00:00

  • Two-dimensional nanoscale structural and functional imaging in individual collagen type I fibrils.

    abstract::The piezoelectric properties of single collagen type I fibrils in fascia were imaged with sub-20 nm spatial resolution using piezoresponse force microscopy. A detailed analysis of the piezoresponse force microscopy signal in controlled tip-fibril geometry revealed shear piezoelectricity parallel to the fibril axis. Th...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2010.02.047

    authors: Harnagea C,Vallières M,Pfeffer CP,Wu D,Olsen BR,Pignolet A,Légaré F,Gruverman A

    更新日期:2010-06-16 00:00:00

  • Bathoproducts of rhodopsin, isorhodopsin I, and isorhodopsin II.

    abstract::Bathorhodopsins were prepared by partially (10--15%) photoconverting bovine rhodopsin (11-cis chromophore) or isorhodopsin I (9-cis chromophore) at 77 degrees K; care was taken to avoid establishing photostationary states. The absorption spectra calculated for the bathorhodopsins derived from the two parent pigments a...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(80)85129-0

    authors: Mao B,Ebrey TG,Crouch R

    更新日期:1980-02-01 00:00:00

  • A simplified model of local structure in aqueous proline amino acid revealed by first-principles molecular dynamics simulations.

    abstract::Aqueous proline solutions are deceptively simple as they can take on complex roles such as protein chaperones, cryoprotectants, and hydrotropic agents in biological processes. Here, a molecular level picture of proline/water mixtures is developed. Car-Parrinello ab initio molecular dynamics (CPAIMD) simulations of aqu...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.108.134916

    authors: Troitzsch RZ,Tulip PR,Crain J,Martyna GJ

    更新日期:2008-12-01 00:00:00

  • Macromolecular size-and-shape distributions by sedimentation velocity analytical ultracentrifugation.

    abstract::Sedimentation velocity analytical ultracentrifugation is an important tool in the characterization of macromolecules and nanoparticles in solution. The sedimentation coefficient distribution c(s) of Lamm equation solutions is based on the approximation of a single, weight-average frictional coefficient of all particle...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.106.081372

    authors: Brown PH,Schuck P

    更新日期:2006-06-15 00:00:00

  • Inhibition of lactoperoxidase by its own catalytic product: crystal structure of the hypothiocyanate-inhibited bovine lactoperoxidase at 2.3-A resolution.

    abstract::To the best of our knowledge, this is the first report on the structure of product-inhibited mammalian peroxidase. Lactoperoxidase is a heme containing an enzyme that catalyzes the inactivation of a wide range of microorganisms. In the presence of hydrogen peroxide, it preferentially converts thiocyanate ion into a to...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2008.09.019

    authors: Singh AK,Singh N,Sharma S,Shin K,Takase M,Kaur P,Srinivasan A,Singh TP

    更新日期:2009-01-01 00:00:00

  • Preformed oligomeric epidermal growth factor receptors undergo an ectodomain structure change during signaling.

    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

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(02)75585-9

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

    更新日期:2002-05-01 00:00:00

  • The electronic structure of Fe2+ in reaction centers from Rhodopseudomonas sphaeroides. I. Static magnetization measurements.

    abstract::We have measured the static magnetization of unreduced and reduced reaction centers that vary in their quinone content. Measurements were performed in the temperature range 0.7 degrees K less than T less than 200 degrees K and magnetic fields of up to 10 kG. The electronic g-value, crystal field parameters D, E, and t...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(80)85030-2

    authors: Butler WF,Johnston DC,Shore HB,Fredkin DR,Okamura MY,Feher G

    更新日期:1980-12-01 00:00:00

  • Polyphosphoinositide inclusion in artificial lipid bilayer vesicles promotes divalent cation-dependent membrane fusion.

    abstract::Recent studies suggest that phosphoinositide kinases may participate in intracellular trafficking or exocytotic events. Because both of these events ultimately require fusion of biological membranes, the susceptibility of membranes containing polyphosphoinositides (PPIs) to divalent cation-induced fusion was investiga...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(96)79513-9

    authors: Summers SA,Guebert BA,Shanahan MF

    更新日期:1996-12-01 00:00:00

  • Motor-like Properties of Nonmotor Enzymes.

    abstract::Molecular motors are thought to generate force and directional motion via nonequilibrium switching between energy surfaces. Because all enzymes can undergo such switching, we hypothesized that the ability to generate rotary motion and torque is not unique to highly adapted biological motor proteins but is instead a co...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2018.02.008

    authors: Slochower DR,Gilson MK

    更新日期:2018-05-08 00:00:00

  • X-rays and nitrogen mustard: independent action in Chinese hamster cells.

    abstract::We have studied the combined effects of X-irradiation and nitrogen mustard treatment on the colony-forming ability of Chinese hamster cells. In contrast to X-irradiation, nitrogen mustard acting by itself yields an exponential dose-effect relationship. Moreover, whether delivered in immediate sequence or after varying...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(69)86439-8

    authors: Sakamoto K,Elkind MM

    更新日期:1969-09-01 00:00:00

  • Cartilage aggrecan can undergo self-adhesion.

    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

    authors: Han L,Dean D,Daher LA,Grodzinsky AJ,Ortiz C

    更新日期:2008-11-15 00:00:00

  • Electrostatic model of S4 motion in voltage-gated ion channels.

    abstract::The S4 transmembrane domain of the family of voltage-gated ion channels is generally thought to be the voltage sensor, whose translocation by an applied electric field produces the gating current. Experiments on hSkMI Na(+) channels and both Shaker and EAG K(+) channels indicate which S4 residues cross the membrane-so...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(03)74708-0

    authors: Lecar H,Larsson HP,Grabe M

    更新日期:2003-11-01 00:00:00