Abstract:
:The published reports of flash-induced absorbance changes in the 680-690 nm spectral region, which have been attributed to bleaching of the primary reaction center chlorophyll of photosystem II (PSII) P-680, are discussed in light of what is known about the primary electron acceptor of PSII, C-550. The question of whether the fluorescence yield changes, which accompany the photoreduction of C-550, might influence the measurements of chlorophyll bleaching is examined. The responses attributed to P-680 and their relationship to C-550 indicate that, if the absorbance measurements are valid, P-680 probably functions as the primary electron donor to PSII rather than as a photochemical sensitizer of the primary redox reaction.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Butler WLdoi
10.1016/S0006-3495(72)86128-9subject
Has Abstractpub_date
1972-07-01 00:00:00pages
851-7issue
7eissn
0006-3495issn
1542-0086pii
S0006-3495(72)86128-9journal_volume
12pub_type
杂志文章abstract::Recent suggestions of nanoscale heat confinement on the surface of synthetic and biogenic magnetic nanoparticles during heating by radio frequency-alternating magnetic fields have generated intense interest because of the potential utility of this phenomenon for noninvasive control of biomolecular and cellular functio...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.01.028
更新日期:2020-03-24 00:00:00
abstract::Cell motion is driven by interplay between the actin cytoskeleton and the cell adhesions in the front part of the cell. The actin network segregates into lamellipodium and lamellum, whereas the adhesion complexes are characteristically distributed underneath the actin system. Here, we suggest a computational model for...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.03.006
更新日期:2012-04-18 00:00:00
abstract::A simple theoretical analysis shows that specificity of double-stranded DNA (dsDNA) targeting by homopyrimidine peptide nucleic acids (hpyPNAs) is a kinetically controlled phenomenon. Our computations give the optimum conditions for sequence-specific targeting of dsDNA by hpyPNAs. The analysis shows that, in agreement...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78918-5
更新日期:1997-06-01 00:00:00
abstract::Structural transition can be induced in charged micelles by increasing the ionic strength of the medium. We have monitored the organization and dynamics of the functionally important tryptophan residues of gramicidin in spherical and rod-shaped sodium dodecyl sulfate micelles utilizing a combination of wavelength-sele...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.060798
更新日期:2005-11-01 00:00:00
abstract::Raman spectroscopic data indicate that the conformations of the two hydrocarbon chains of dipalmitoyl phosphatidylcholine in aqueous dispersions of the lipid differ signficantly. The compounds 1-palmitoyl, 2-palmitoyl-d31-3-sn-phosphatidylcholine and 1-palmitoyl-d31, 2-palmitoyl-3-sn-phosphatidylcholine were synthesiz...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(78)85413-7
更新日期:1978-12-01 00:00:00
abstract::We developed a kinetic model for a single-substrate trimolecular enzymatic system, where a receptor binds and stretches a substrate to expose its cleavage site, allowing an enzyme to bind and cleave it into product. We demonstrated that the general kinetics of the trimolecular enzymatic system is more complex than the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.01.020
更新日期:2010-05-19 00:00:00
abstract::To map the binding sites involved in channel formation, synthetic peptides representing sequences of connexin 32 were tested for their ability to inhibit cell-cell channel formation. Both large peptides representing most of the two presumed extracellular loops of connexin32 and shorter peptides representing subsets of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(94)80663-0
更新日期:1994-11-01 00:00:00
abstract::Cellular membranes are laterally organized into domains of distinct structures and compositions by the differential interaction affinities between various membrane lipids and proteins. A prominent example of such structures are lipid rafts, which are ordered, tightly packed domains that have been widely implicated in ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.03.020
更新日期:2018-04-24 00:00:00
abstract::We have used identified neurons from the abdominal ganglion of the mollusc Aplysia to construct and analyze two circuits in vitro. Each of these circuits was capable of producing two patterns of persistent activity; that is, they had bistable output states. The output could be switched between the stable states by a b...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82591-1
更新日期:1990-04-01 00:00:00
abstract::The excitation of the squid giant axon that had been perfused intra- and extracellularly with solutions containing a high concentration of glycerol could be observed below 0 degree C. The action potential could be elicited at normal strengths of electrical stimuli. The time-course of the action potential was slowed, w...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(81)84785-6
更新日期:1981-07-01 00:00:00
abstract::We are interested in modeling the membrane-spanning domain of the serotonin 5-HT1A G-protein coupled receptor. This superfamily of proteins is predicted to share the topology of the seven transmembrane helices of bacteriorhodopsin (BR), even though no significant sequence homology had been identified. We found signifi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81794-0
更新日期:1992-04-01 00:00:00
abstract::Fluorescence fluctuation spectroscopy has become an important measurement tool for investigating molecular dynamics, molecular interactions, and chemical kinetics in biological systems. Although the basic theory of fluctuation spectroscopy is well established, it is not widely recognized that saturation of the fluores...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.052779
更新日期:2005-09-01 00:00:00
abstract::A simple method of generating electric field-induced concentration gradients in planar supported bilayers has been developed. Gradients of charged, fluorescently labeled probes were visualized by epifluorescence microscopy and could be observed at field strengths as low as 1 V/cm. Steady-state concentration gradients ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80067-6
更新日期:1995-11-01 00:00:00
abstract::Reconstruction of genome-scale metabolic networks is now possible using multiple different data types. Constraint-based modeling is an approach to interrogate capabilities of reconstructed networks by constraining possible cellular behavior through the imposition of physicochemical laws. As a result, a steady-state fl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.043000
更新日期:2004-10-01 00:00:00
abstract::The molecular basis of the activation of G-proteins by the G-protein coupled receptor for parathyroid hormone (PTH) is unknown. Employing a combination of NMR methods and computer-based structural refinement, structural features involved in the activation of Galpha(s) by the PTH receptor (PTH1R) have been determined. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.094813
更新日期:2007-01-15 00:00:00
abstract::Specific amino acid sequence segments have been assigned to locations in the structural map of bacteriorhodopsin using two-dimensional neutron diffraction data and a model building analysis. Models are constructed computationally by building specific regions of the amino acid sequence as alpha helices and then positio...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84391-4
更新日期:1983-06-01 00:00:00
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
更新日期:1997-05-01 00:00:00
abstract::The effect of electric fields on dry oriented multibilayers of dimyristoylphosphatidylcholine (DMPC) was investigated by transmission Fourier transform infrared electric field modulated excitation (E-ME) spectroscopy. A periodic rectangular electric potential (0-150 V, 1.25 Hz, 28.4 degrees C +/- 0.2 degrees C) was ap...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74104-1
更新日期:2004-01-01 00:00:00
abstract::A sample preparation method using spherical glass ampoules has been used to achieve 1.5-Hz resolution in 1H magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of aqueous multilamellar dispersions of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (P...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77205-X
更新日期:1999-01-01 00:00:00
abstract::Molecular dynamics simulations in simplified models allow one to study the scaling properties of folding times for many proteins together under a controlled setting. We consider three variants of the Go models with different contact potentials and demonstrate scaling described by power laws and no correlation with the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74867-X
更新日期:2003-01-01 00:00:00
abstract::Lateral organization of cholesterol in dioleoyl-phosphatidylcholine (DOPC) lipid bilayers at high cholesterol concentration (>45 mol%) was investigated using steady-state fluorescence anisotropy and fluorescent resonance energy transfer techniques. The recently devised Low Temperature Trap method was used to prepare c...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74221-6
更新日期:2004-03-01 00:00:00
abstract::Many cell cytoskeletons include an aster of microtubules, with the centrosome serving as the focal point. The position of the centrosome within the cell is important in such directional activities as wound closure and interactions of immune cells. Here we analyzed the centrosome positioning as it is dictated by microt...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.09.017
更新日期:2010-11-03 00:00:00
abstract::The giant protein titin is responsible for the elasticity of nonactivated muscle sarcomeres. Titin-based passive stiffness in myocardium is modulated by titin-isoform switching and protein-kinase (PK)A- or PKG-dependent titin phosphorylation. Additional modulatory effects on titin stiffness may arise from disulfide bo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.05.037
更新日期:2009-08-05 00:00:00
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
更新日期:2010-04-21 00:00:00
abstract::The effect of a transmembrane peptide on the domain structure of a two-component, two-phase lipid bilayer composed of dimyristoyl phosphatidylcholine (DMPC) and distearoyl phosphatidylcholine (DSPC) was examined by spin label electron spin resonance (ESR) spectroscopy. The peptide, pOmpA, is the hydrophobic, 25-residu...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(94)80989-0
更新日期:1994-06-01 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::The formulation of Lorente de Nó for the potential distribution in a volume conductor due to a contained bioelectric source is reviewed. The aforementioned formula is based on data taken from the bioelectric source in air (excised). This work is extended to the derivation of a formula which depends upon quantities ava...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(64)86785-0
更新日期:1964-07-01 00:00:00
abstract::Structure factor amplitudes and phases can be computed directly from electron cryomicroscopy images. Inherent aberrations of the electromagnetic lenses and other instrumental factors affect the structure factors, however, resulting in decreased accuracy in the determined three-dimensional reconstruction. In contrast, ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77381-9
更新日期:1999-04-01 00:00:00
abstract::Analyses of receptor-ligand interactions are important to the understanding of cellular adhesion. Traditional methods of measuring the three-dimensional (3D) dissociation constant (Kd) require at least one of the molecular species in solution and hence cannot be directly applied to the case of cell adhesion. We descri...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77807-5
更新日期:1998-01-01 00:00:00
abstract::The development of scanning probe techniques has made it possible to examine protein-protein interactions at the level of individual molecular pairs. A calibrated optical tweezers, along with immunoglobulin G (IgG)-coated polystyrene microspheres, has been used to detect individual surface-linked Staphylococcus protei...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76263-7
更新日期:2001-06-01 00:00:00