Abstract:
:Diffusional encounters between a dumbbell model of a cleft enzyme and a dumbbell model of an elongated ligand are simulated by Brownian dynamics. The simulations take into account electrostatic and hydrodynamic interactions between the molecules. It is shown that the primary effect of inclusion of hydrodynamic interactions into the simulation is an overall decrease in the rate constant. Hydrodynamic orientational effects are of modest size for the systems considered here. They are manifested when changes in the rate constants for diffusional encounters favored by hydrodynamic interactions are compared with those favored by electrostatic interactions as functions of the overall strength of electrostatic interactions. The electrostatic interactions modify the hydrodynamic torques by modifying the drift velocity of the substrate toward the enzyme. We conclude that simulations referring only to electrostatic interactions between an enzyme and its ligand may yield rate constants that are somewhat (e.g., 20%) too high, but provide realistic descriptions of the orientational steering effects in the enzyme-ligand encounters.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Antosiewicz J,McCammon JAdoi
10.1016/S0006-3495(95)79874-5subject
Has Abstractpub_date
1995-07-01 00:00:00pages
57-65issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(95)79874-5journal_volume
69pub_type
杂志文章abstract::The partition coefficients (K(P)) of a series of single-chain and double-chain fluorescent amphiphiles, between solid ordered (P(beta') and L(beta)) and liquid disordered (L(alpha) of the type l(d)) lipid phases coexisting in the same lipid bilayer, was studied using steady-state fluorescence emission anisotropy. The ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76840-8
更新日期:2000-06-01 00:00:00
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journal_title:Biophysical journal
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journal_title:Biophysical journal
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更新日期:1989-08-01 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:1964-03-01 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:1997-02-01 00:00:00
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pub_type: 杂志文章
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journal_title:Biophysical journal
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更新日期:2004-04-01 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:1981-06-01 00:00:00
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pub_type: 杂志文章
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更新日期:2015-03-24 00:00:00
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pub_type: 杂志文章
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更新日期:2013-03-05 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.134569
更新日期:2008-12-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.08.059
更新日期:2011-11-16 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.02.047
更新日期:2010-06-16 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79929-5
更新日期:1995-08-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77507-1
更新日期:1998-07-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.102681
更新日期:2007-07-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(84)84051-5
更新日期:1984-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:2000-11-01 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:2006-12-15 00:00:00
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更新日期:1996-01-01 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:2014-03-18 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:1989-03-01 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:2012-07-03 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)73915-5
更新日期:2002-09-01 00:00:00
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journal_title:Biophysical journal
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更新日期:2015-08-04 00:00:00
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journal_title:Biophysical journal
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更新日期:2005-05-01 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:2020-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.01.012
更新日期:2017-10-03 00:00:00
abstract::Lateral mobility of molecules on cell membranes has been recently studied by fluorescence photobleaching recovery (FPR) techniques. The interpretation of these results in terms of diffusion along the membranes is based on the assumption that the surface is planar, although biological membranes may have blebs and micro...
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pub_type: 杂志文章
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更新日期:1982-06-01 00:00:00