Abstract:
:Adaptation of the attractant response in Escherichia coli is attributable to the methylation of its transmembrane chemotactic receptors by the methyltransferase CheR. This protein contains two binding domains, one for the sites of methylation themselves and the other for a flexible tether at the C terminus of the receptor. We have explored the theoretical consequences of this binding geometry for a CheR molecule associated with a cluster of chemotactic receptors. Calculations show that the CheR molecule will bind with high net affinity to the receptor lattice, having a high probability of being attached by one or both of its domains at any instant of time. Because of the relatively low affinity of its individual domains and the close proximity of neighboring receptors, it is likely that when one domain unbinds it will reattach to the array before the other domain unbinds. Stochastic simulations show that the enzyme will move through the receptor cluster in a hand-over-hand fashion, like a gibbon swinging through the branches of a tree. We explore the possible consequences of this motion, which we term "molecular brachiation", for chemotactic adaptation and suggest that a similar mechanism may be operative in other large assemblies of protein molecules.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Levin MD,Shimizu TS,Bray Ddoi
10.1016/S0006-3495(02)75531-8subject
Has Abstractpub_date
2002-04-01 00:00:00pages
1809-17issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(02)75531-8journal_volume
82pub_type
杂志文章abstract::A two-dimensional stochastic model for the dynamics of microtubules in gliding-assay experiments is presented here, which includes the viscous drag acting on the moving fiber and the interaction with the kinesins. For this purpose, we model kinesin as a spring, and explicitly use parameter values to characterize the m...
journal_title:Biophysical journal
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更新日期:2001-06-01 00:00:00
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journal_title:Biophysical journal
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更新日期:1996-09-01 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:2005-02-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2002-06-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/j.bpj.2015.02.016
更新日期:2015-03-24 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:1998-02-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(65)86740-6
更新日期:1965-09-01 00:00:00
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pub_type: 杂志文章
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更新日期:1992-05-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83788-7
更新日期:1985-08-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82444-9
更新日期:1990-10-01 00:00:00
abstract::Xenopus melanophores have pigment organelles or melanosomes which, in response to hormones, disperse in the cytoplasm or aggregate in the perinuclear region. Melanosomes are transported by microtubule motors, kinesin-2 and cytoplasmic dynein, and an actin motor, myosin-V. We explored the regulation of melanosome trans...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.067843
更新日期:2006-01-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(76)85769-4
更新日期:1976-10-01 00:00:00
abstract::The relative contributions of the allosteric and affinity factors toward the change in p50 have been calculated for a series of effectors of hemoglobin (Hb). Shifts in the ligand affinity of deoxy Hb and the values for 50% ligand saturation (p50) were obtained from oxygen equilibrium data. Because the high-affinity pa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82556-X
更新日期:1990-03-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77952-4
更新日期:1998-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77159-6
更新日期:1999-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(80)85078-8
更新日期:1980-04-01 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:1992-05-01 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:2017-09-05 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(86)83692-X
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(94)80715-5
更新日期:1994-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79415-8
更新日期:1996-10-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(75)85823-1
更新日期:1975-04-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.08.029
更新日期:2011-10-05 00:00:00
abstract::In the first issue, on the first page of the Biophysical Journal in 1960, Cole and Moore provided the first confirmation of the Hodgkin and Huxley formulation of the sodium and potassium conductances that underlie the action potential. In addition, working with the squid giant axon, Cole and Moore noted that strong hy...
journal_title:Biophysical journal
pub_type: 历史文章,杂志文章
doi:10.1016/j.bpj.2015.07.052
更新日期:2015-10-06 00:00:00
abstract::Dielectrophoresis and electrorotation are commonly used to measure dielectric properties and membrane electrical parameters of biological cells. We have derived quantitative relationships for several critical points, defined in Fig. A 1, which characterize the dielectrophoretic spectrum and the electrorotational spect...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82109-9
更新日期:1991-10-01 00:00:00
abstract::A sequence determinant of reduction potentials is reported for bacterial [4Fe-4S]-type ferredoxins. The residue that is four residues C-terminal to the fourth ligand of either cluster is generally an alanine or a cysteine. In five experimental ferredoxin structures, the cysteine has the same structural orientation rel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(01)75726-8
更新日期:2001-08-01 00:00:00
abstract::We study theoretically the feasibility of using transverse electronic transport within a nanopore for rapid DNA sequencing. Specifically, we examine the effects of the environment and detection probes on the distinguishability of the DNA bases. We find that the intrinsic measurement bandwidth of the electrodes helps t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.102269
更新日期:2007-10-01 00:00:00
abstract::Loss of myelin in the central nervous system (CNS) leads to debilitating neurological deficits. High-resolution optical imaging of myelin in the CNS of animal models is limited by a lack of in vivo myelin labeling strategies. We demonstrated that third harmonic generation (THG) microscopy-a coherent, nonlinear, dye-fr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.01.031
更新日期:2011-03-02 00:00:00
abstract::We have constructed a model of the upper part of the glycolysis in the pancreatic beta-cell. The model comprises the enzymatic reactions from glucokinase to glyceraldehyde-3-phosphate dehydrogenase (GAPD). Our results show, for a substantial part of the parameter space, an oscillatory behavior of the glycolysis for a ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74460-9
更新日期:2003-07-01 00:00:00