Abstract:
:The effect of the presence of a minor antenna component in light-harvesting complexes of photosynthetic bacteria is investigated with numerical simulation employing the transition probability matrix method. A model antenna system of hexagonal symmetry is adopted, using as a working hypothesis that the minor component forms a ring around the trap. Three cases have been considered: (a) the minor component is isoenergetic with the trap, which is at lower energy than the antennas (the "supertrap"), (b) the minor component is at lower energy than the trap, which is at lower energy than the antennas (the "asymmetric gutter"), (c) the minor component is at lower energy than the trap, which is isoenergetic with the antennas (the "gutter"). It is found that the supertrap speeds up the fluorescence decay and enhances the trapping efficiency, whereas the gutter slows down the fluorescence decay and decreases the trapping efficiency. It is concluded that, in contrast to a recent suggestion (Bergström, H., R. van Grondelle, and V. Sundström. 1989. FEBS (Fed. Eur. Biochem. Soc.) Lett. 250:503-508), concentrating excitations in the vicinity of the trap by the so-called long-wavelength minor antenna component purportedly present in Rhodobacter sphaeroides and Rhodospirillum rubrum instead of improving trapping actually impedes trapping.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Fischer MR,Hoff AJdoi
10.1016/S0006-3495(92)81689-2subject
Has Abstractpub_date
1992-10-01 00:00:00pages
911-6issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(92)81689-2journal_volume
63pub_type
杂志文章abstract::Cysteine residues introduced by site-directed mutagenesis have been used to probe the conformation and dynamics of two receptors in the E. coli chemotaxis pathway. (a) Thermal motions of the polypeptide backbone were investigated in the periplasmic D-galactose and D-glucose receptor, a globular protein of known struct...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81806-4
更新日期:1992-04-01 00:00:00
abstract::Excised inside-out membrane patches are useful for studying the cGMP-activated ion channels that generate the electrical response to light in retinal rod cells. We show that strong ionic current across a patch changes the driving force on the current by altering the ionic concentration near the surface membrane, an ef...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(88)82966-7
更新日期:1988-08-01 00:00:00
abstract::The current-voltage (I-V) relation of the background current, IK1, was studied in isolated canine cardiac Purkinje myocytes using the whole-cell, patch-clamp technique. Since Ba2+ and Cs+ block IK1, these cations were used to separate the I-V relation of IK1 from that of the whole cell. The I-V relation of IK1 was mea...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(87)83241-1
更新日期:1987-10-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.01.031
更新日期:2016-03-29 00:00:00
abstract::A recent thermodynamic model describes a reversible reaction between cholesterol (C) and phospholipid (P) to form a condensed complex C(nq)P(np). Here q and p are relatively prime integers used to define the stoichiometric composition, and n is a measure of cooperativity. The present study applies this model to the sc...
journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2001-11-01 00:00:00
abstract::Downstream processes that discriminate between DNA adducts of a third generation platinum antitumor drug oxaliplatin and conventional cisplatin are believed to be responsible for the differences in their biological effects. These different biological effects are explained by the ability of oxaliplatin to form DNA addu...
journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2007-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.01.006
更新日期:2009-04-08 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81343-2
更新日期:1993-01-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.084673
更新日期:2006-06-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1979-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2010-04-07 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.11.011
更新日期:2010-03-03 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78155-4
更新日期:1997-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82746-8
更新日期:1989-11-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.138685
更新日期:2008-11-15 00:00:00
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pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82316-5
更新日期:1991-05-01 00:00:00
abstract::Clathrin-coated membranes are precursors to coated vesicles in the receptor-mediated endocytic pathway. In this paper we present a physical model for the first steps of the transformation of a clathrin-coated membrane into a coated vesicle. The theory is based on in vitro cytoplasmic acidification experiments of Heuse...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77993-7
更新日期:1998-06-01 00:00:00
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
更新日期:1980-02-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1994-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:1993-06-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2007-05-15 00:00:00
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更新日期:2009-06-17 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1998-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1995-10-01 00:00:00
abstract::Two T = 1 and one T = 3 plant viruses, along with a protein, were crystallized in microgravity during the International Microgravity Laboratory-2 (IML-2) mission in July of 1994. The method used was liquid-liquid diffusion in the European Space Agency's Advanced Protein Crystallization Facility (APCF). Distinctive alt...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79890-3
更新日期:1995-07-01 00:00:00
abstract::The conformation of mononucleosome complexes reconstituted with recombinant core histones on a 614-basepair-long DNA fragment containing the Xenopus borealis 5S rRNA nucleosome positioning sequence was studied by scanning/atomic force microscopy in the absence or presence of linker histone H1. Imaging without prior fi...
journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2003-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1967-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2009-01-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.050203
更新日期:2005-02-01 00:00:00
abstract::The effect of antibodies to glycophorin A on the rotational diffusion of band 3 in human erythrocyte membranes was investigated by transient dichrosim. Three antibodies that recognize different epitopes on the exofacial domain of glycophorin A all strongly reduce the rotational mobility of band 3. The effect is at mos...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80365-6
更新日期:1995-05-01 00:00:00