The dependence of the shapes of fluorescence induction curves in chloroplasts on the duration of illumination pulses.

Abstract:

:The shapes of fluorescence induction curves in spinach chloroplasts, measured using double-flash pump-probe techniques, are shown to depend on the duration of the actinic flashes. For flash durations tau(0) /= 50 mus, the shapes of the F(nu) vs. J curves are sigmoidal, and R > 3.2. Overall, the experimentally observed trends suggest that, as the duration tau(0) of the actinic pulses is increased, the degree of sigmoidicity, the deduced values of the interunit excitation transfer parameter p, and the fluorescence induction ratios R, also tend to increase. These results can be accounted for in terms of a simple double-photon hit model in which a dark lag time tau(1) = 0.4-10 mus between the two hits is necessary for the observance of sigmoidal fluorescence induction curves and relatively high R ratios. It is shown that, in principle, such a model can account for the exponential and sigmoidal shapes of the fluorescence induction curves either within the context of a lake model of the photosynthetic antenna bed (free transfer of excitation between photosynthetic units) or the isolated (puddle) model of photosystem II reaction centers. However, from the known values of the R ratio measured with actinic pulses of different durations, or under continuous illumination, the lake model offers a better description of the experimental phenomena than the puddle model.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Valkunas L,Geacintov NE,France L,Breton J

doi

10.1016/S0006-3495(91)82233-0

subject

Has Abstract

pub_date

1991-02-01 00:00:00

pages

397-408

issue

2

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(91)82233-0

journal_volume

59

pub_type

杂志文章
  • On the mechanism of ATP hydrolysis in F1-ATPase.

    abstract::Most of the cellular ATP in living organisms is synthesized by the enzyme F(1)F(o)-ATP synthase. The water soluble F(1) part of the enzyme can also work in reverse and utilize the chemical energy released during ATP hydrolysis to generate mechanical motion. Despite the availability of a large amount of biochemical dat...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(03)74650-5

    authors: Dittrich M,Hayashi S,Schulten K

    更新日期:2003-10-01 00:00:00

  • Ca channel gating during cardiac action potentials.

    abstract::How do Ca channels conduct Ca ions during the cardiac action potential? We attempt to answer this question by applying a two-microelectrode technique, previously used for Na and K currents, in which we record the patch current and the action potential at the same time (Mazzanti, M., and L. J. DeFelice. 1987. Biophys. ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(90)82448-6

    authors: Mazzanti M,DeFelice LJ

    更新日期:1990-10-01 00:00:00

  • Events leading to the opening and closing of the exocytotic fusion pore have markedly different temperature dependencies. Kinetic analysis of single fusion events in patch-clamped mouse mast cells.

    abstract::The earliest event in exocytosis is the formation of a fusion pore, an aqueous channel that connects the lumen of a secretory granule with the extracellular space. We can observe the formation of individual fusion pores and their subsequent dilation or closure by measuring the changes in the admittance of patch-clampe...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(92)81884-2

    authors: Oberhauser AF,Monck JR,Fernandez JM

    更新日期:1992-03-01 00:00:00

  • Molecular mechanisms of how mercury inhibits water permeation through aquaporin-1: understanding by molecular dynamics simulation.

    abstract::Aquaporin (AQP) functions as a water-conducting pore. Mercury inhibits the water permeation through AQP. Although site-directed mutagenesis has shown that mercury binds to Cys189 during the inhibition process, it is not fully understood how this inhibits the water permeation through AQP1. We carried out 40 ns molecula...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2009.12.4310

    authors: Hirano Y,Okimoto N,Kadohira I,Suematsu M,Yasuoka K,Yasui M

    更新日期:2010-04-21 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

  • Force versus axial deflection of pipette-aspirated closed membranes.

    abstract::The axial deformation of a pipette-pressurized fluid membrane bag produces minuscule yet well-defined, reproducible forces. The stiffness of this ultrasensitive force transducer is tunable and largely independent of the constitutive membrane behavior. Based on a rigorous variational treatment, we present both numerica...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.107.104091

    authors: Heinrich V,Ounkomol C

    更新日期:2007-07-15 00:00:00

  • The effect of a variable dielectric coefficient and finite ion size on Poisson-Boltzmann calculations of DNA-electrolyte systems.

    abstract::The results of variable dielectric coefficient Poisson-Boltzmann calculations of the counter-ion concentration in the vicinity of an all-atom model of the B-form of DNA are presented with an emphasis on the importance of spatial variations in the dielectric properties of the solvent, particularly at the macro-ion-solv...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(93)81187-1

    authors: Pack GR,Garrett GA,Wong L,Lamm G

    更新日期:1993-10-01 00:00:00

  • Subconductance states in single-channel activity of skeletal muscle ryanodine receptors after removal of FKBP12.

    abstract::FKBP12 was removed from ryanodine receptors (RyRs) by incubation of rabbit skeletal muscle terminal cisternae membranes with rapamycin. The extent of FKBP12 removal was estimated by immunostaining Western blots of terminal cisternae proteins. Single FKBP12-depleted RyR channels, incorporated into planar lipid bilayers...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(97)78654-5

    authors: Ahern GP,Junankar PR,Dulhunty AF

    更新日期:1997-01-01 00:00:00

  • Molecular dynamics simulation of carboxy-myoglobin embedded in a trehalose-water matrix.

    abstract::We report on a molecular dynamics (MD) simulation of carboxy-myoglobin (MbCO) embedded in a water-trehalose system. The mean square fluctuations of protein atoms, calculated at different temperatures in the 100-300 K range, are compared with those from a previous MD simulation on an H2O-solvated MbCO and with experime...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(01)76072-9

    authors: Cottone G,Cordone L,Ciccotti G

    更新日期:2001-02-01 00:00:00

  • Local oxygen gradients near isolated mitochondria.

    abstract::The oxygen concentration in tissue can vary on several length scales. The basic scale of variation is determined by capillary spacing. It is this scale that is manifest in the simplest Krogh cylinder model. A second, smaller scale of variation is associated with the consumption of oxygen by mitochondria. This paper gi...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(85)83856-X

    authors: Clark A Jr,Clark PA

    更新日期:1985-12-01 00:00:00

  • Helical conformation of the SEVI precursor peptide PAP248-286, a dramatic enhancer of HIV infectivity, promotes lipid aggregation and fusion.

    abstract::In previous in vivo studies, amyloid fibers formed from a peptide ubiquitous in human seminal fluid (semen-derived enhancer of viral infection (SEVI)) were found to dramatically enhance the infectivity of the HIV virus (3-5 orders of magnitude by some measures). To complement those studies, we performed in vitro assay...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2009.08.034

    authors: Brender JR,Hartman K,Gottler LM,Cavitt ME,Youngstrom DW,Ramamoorthy A

    更新日期:2009-11-04 00:00:00

  • Reconstruction of a kinetic model of the chromatophore vesicles from Rhodobacter sphaeroides.

    abstract::We present a molecular model of a chromatophore vesicle from Rhodobacter sphaeroides. These vesicles are ideal benchmark systems for molecular and systemic simulations, because they have been well studied, they are small, and they are naturally separated from their cellular environment. To set up a photosynthetic chai...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.067561

    authors: Geyer T,Helms V

    更新日期:2006-08-01 00:00:00

  • Effects of bath resistance on action potentials in the squid giant axon: myocardial implications.

    abstract::This study presents a simplified version of the quasi-one-dimensional theory (Wu, J., E. A. Johnson, and J. M. Kootsey. 1996. A quasi-one-dimensional theory for anisotropic propagation of excitation in cardiac muscle. Biophys. J. 71:2427-2439) with two components of the extracellular current, along and perpendicular t...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(97)78265-1

    authors: Wu J,Wikswo JP Jr

    更新日期:1997-11-01 00:00:00

  • Near-infrared spectra of Scapharca homodimeric hemoglobin: characterization of the deoxy and photodissociated derivatives.

    abstract::The near-infrared charge transfer band at 760 nm (band III) has been investigated in deoxy and photodissociated dimeric Scapharca hemoglobin. At 300 K, the 10-ns spectrum of the carbonmonoxy derivative photoproduct is shifted by about 6 nm toward longer wavelengths with respect to the deoxy spectrum, both in buffer an...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(96)79862-4

    authors: Huang J,Leone M,Boffi A,Friedman JM,Chiancone E

    更新日期:1996-06-01 00:00:00

  • An anionic phospholipid enables the hydrophobic surfactant proteins to alter spontaneous curvature.

    abstract::The hydrophobic surfactant proteins, SP-B and SP-C, greatly accelerate the adsorption of the surfactant lipids to an air/water interface. Previous studies of factors that affect curvature suggest that vesicles may adsorb via a rate-limiting structure with prominent negative curvature, in which the hydrophilic face of ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2012.12.041

    authors: Chavarha M,Loney RW,Rananavare SB,Hall SB

    更新日期:2013-02-05 00:00:00

  • Propagation speed in myelinated nerve. I. Experimental dependence on external Na and on temperature.

    abstract::Conduction speed (theta) in single myelinated Rana pipiens sciatic nerve fibers has been precisely measured using intracellular recording and on-line digital computer techniques. The dependence of relative speed on external Na concentration at 15 degrees C has been found to be ln(theta(1)/theta(2)) = 0.524 (+/-0.018) ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(73)86045-X

    authors: Hardy WL

    更新日期:1973-10-01 00:00:00

  • Rates and Equilibrium of CuA to heme a electron transfer in Paracoccus denitrificans cytochrome c oxidase.

    abstract::Intramolecular electron transfer between CuA and heme a in solubilized bacterial (Paracoccus denitrificans) cytochrome c oxidase was investigated by pulse radiolysis. CuA, the initial electron acceptor, was reduced by 1-methylnicotinamide radicals in a diffusion-controlled reaction, as monitored by absorption changes ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.075440

    authors: Farver O,Grell E,Ludwig B,Michel H,Pecht I

    更新日期:2006-03-15 00:00:00

  • Molecular heterogeneity of O-acetylserine sulfhydrylase by two-photon excited fluorescence fluctuation spectroscopy.

    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

    authors: Chirico G,Bettati S,Mozzarelli A,Chen Y,Müller JD,Gratton E

    更新日期:2001-04-01 00:00:00

  • Endocytosis Is a Key Mode of Interaction between Extracellular β-Amyloid and the Cell Membrane.

    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

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2020.07.035

    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

  • Phospholipid-dependent regulation of cytochrome c3-mediated electron transport across membranes.

    abstract::Cytochrome c3 (cyt c3) can mediate electron transport across phosphatidylcholine (PC)/cardiolipin (CL) and PC/phosphatidylglycerol (PG) membranes. A two-molecule process is involved in the electron transport across PC/CL membranes in the liquid-crystalline state. In contrast, a single-molecule process dominates the el...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.105.065359

    authors: Kim SM,Yamamoto T,Todokoro Y,Takayama Y,Fujiwara T,Park JS,Akutsu H

    更新日期:2006-01-15 00:00:00

  • Comparison of the dynamics of the primary events of bacteriorhodopsin in its trimeric and monomeric states.

    abstract::In this paper, femtosecond pump-probe spectroscopy in the visible region of the spectrum has been used to examine the ultrafast dynamics of the retinal excited state in both the native trimeric state and the monomeric state of bacteriorhodopsin (bR). It is found that the excited state lifetime (probed at 490 nm) incre...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(02)73925-8

    authors: Wang J,Link S,Heyes CD,El-Sayed MA

    更新日期:2002-09-01 00:00:00

  • Integral protein linkage and the bilayer-skeletal separation energy in red blood cells.

    abstract::Stabilization of the lipid bilayer membrane in red blood cells by its association with an underlying membrane-associated cytoskeleton has long been recognized as critical for proper red blood cell function. One of the principal connections between skeleton and bilayer is via linkages between band 3, the integral membr...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.108.129163

    authors: Butler J,Mohandas N,Waugh RE

    更新日期:2008-08-01 00:00:00

  • Sodium dodecyl sulfate-resistant complexes of Alzheimer's amyloid beta-peptide with the N-terminal, receptor binding domain of apolipoprotein E.

    abstract::Immunocytochemical, biochemical, and molecular genetic studies indicate that apolipoprotein E (apoE) plays an important role in the process of amyloidogenesis-beta. However, there is still no clear translation of these data into the pathogenesis of amyloidosis-beta. Previous studies demonstrated sodium dodecyl sulfate...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(00)76354-5

    authors: Golabek AA,Kida E,Walus M,Perez C,Wisniewski T,Soto C

    更新日期:2000-08-01 00:00:00

  • The nature of rhodopsin-triggered photocurrents in Chlamydomonas. II. Influence of monovalent ions.

    abstract::Chlamydomonas exhibits a sequence of a photoreceptor current and two flagellar currents upon stimulation with bright green flashes. The currents are thought to be a prerequisite for the well-known photophobic responses. In the preceding paper, we analyzed the kinetics of these currents and their dependence on extracel...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/S0006-3495(96)79636-4

    authors: Nonnengässer C,Holland EM,Harz H,Hegemann P

    更新日期:1996-02-01 00:00:00

  • Comparative Study of the Condensing Effects of Ergosterol and Cholesterol.

    abstract::Cholesterol, due to its condensing effect, is considered an important regulator of membrane thickness. Other sterols, due to their structural similarities to cholesterol, are often assumed to have a universal effect on membrane properties similar to the condensing effect of cholesterol, albeit possibly to different de...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2016.04.003

    authors: Hung WC,Lee MT,Chung H,Sun YT,Chen H,Charron NE,Huang HW

    更新日期:2016-05-10 00:00:00

  • Tropomyosins Regulate the Severing Activity of Gelsolin in Isoform-Dependent and Independent Manners.

    abstract::The actin cytoskeleton fulfills numerous key cellular functions, which are tightly regulated in activity, localization, and temporal patterning by actin binding proteins. Tropomyosins and gelsolin are two such filament-regulating proteins. Here, we investigate how the effects of tropomyosins are coupled to the binding...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2017.11.3812

    authors: Kis-Bicskei N,Bécsi B,Erdődi F,Robinson RC,Bugyi B,Huber T,Nyitrai M,Talián GC

    更新日期:2018-02-27 00:00:00

  • Optical band splitting and electronic perturbations of the heme chromophore in cytochrome C at room temperature probed by visible electronic circular dichroism spectroscopy.

    abstract::We have measured the electronic circular dichroism (ECD) of the ferri- and ferro-states of several natural cytochrome c derivatives (horse heart, chicken, bovine, and yeast) and the Y67F mutant of yeast in the region between 300 and 750 nm. Thus, we recorded the ECD of the B- and Q-band region as well as the charge-tr...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1529/biophysj.106.095976

    authors: Dragomir I,Hagarman A,Wallace C,Schweitzer-Stenner R

    更新日期:2007-02-01 00:00:00

  • Directional persistence of cell migration coincides with stability of asymmetric intracellular signaling.

    abstract::It has long been appreciated that spatiotemporal dynamics of cell migration are under the control of intracellular signaling pathways, which are mediated by adhesion receptors and other transducers of extracellular cues. Further, there is ample evidence that aspects of cell migration are stochastic: how else could it ...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2009.09.051

    authors: Weiger MC,Ahmed S,Welf ES,Haugh JM

    更新日期:2010-01-06 00:00:00

  • Nanomechanical mapping of hydrated rat tail tendon collagen I fibrils.

    abstract::Collagen fibrils play an important role in the human body, providing tensile strength to connective tissues. These fibrils are characterized by a banding pattern with a D-period of 67 nm. The proposed origin of the D-period is the internal staggering of tropocollagen molecules within the fibril, leading to gap and ove...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2014.09.003

    authors: Baldwin SJ,Quigley AS,Clegg C,Kreplak L

    更新日期:2014-10-21 00:00:00

  • Coupled folding-binding in a hydrophobic/polar protein model: impact of synergistic folding and disordered flanks.

    abstract::Coupled folding-binding is central to the function of many intrinsically disordered proteins, yet not fully understood. With a continuous three-letter protein model, we explore the free-energy landscape of pairs of interacting sequences and how it is impacted by 1), variations in the binding mechanism; and 2), the add...

    journal_title:Biophysical journal

    pub_type: 杂志文章

    doi:10.1016/j.bpj.2011.12.008

    authors: Bhattacherjee A,Wallin S

    更新日期:2012-02-08 00:00:00