Abstract:
:A continuum model is provided of the free energy terms that contribute to the molecular association of ricin A-chain (RTA) with the rRNA substrate and several small ligands. The model for RTA interactions with the RNA was taken from a previously proposed complex containing a 29-mer oligonucleotide hairpin (. Proteins 27:80-95), and models for the ligands were constructed from x-ray crystallographic structures. The calculated absolute free energies of complex formation for the RTA-RNA assembly and several single-residue substitutions are in good agreement with experimental data, given the approximations of evaluating the strain energy and conformational entropy. The free energy terms were found to resemble those of protein-protein complexes, with the net unfavorable electrostatic contribution offset by the favorable nonspecific hydrophobic effect. Decomposition of the RTA-RNA binding free energy into individual contributions revealed the electrostatic "hot" spots arising from charge-charge complementarity of the interfacial arginines with the RNA phosphate backbone. Base interactions of the GAGA loop structure dominate the hydrophobic complementarity. A linear-scaling model was parametrized for evaluating the binding of small ligands against the rRNA substrate and illustrates the free energy determinant required for designing specific RTA inhibitors.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Olson MA,Cuff Ldoi
10.1016/S0006-3495(99)77175-4subject
Has Abstractpub_date
1999-01-01 00:00:00pages
28-39issue
1 Pt 1eissn
0006-3495issn
1542-0086pii
S0006-3495(99)77175-4journal_volume
76pub_type
杂志文章abstract::The quantitation of human granulocyte movement using a stochastic differential equation is described. The method has the potential to distinguish both positive and negative chemotaxis. Analysis and information concerning cell movements can be obtained for any point in time and distance for the duration of the experime...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(76)85685-8
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abstract::Catch force in molluscan smooth muscle requires little, if any, energy input and is controlled by the phosphorylation state of the thick filament-associated mini-titin, twitchin. The kinetic parameters of myosin cross-bridge turnover in permeabilized catch muscle, and how they are potentially modified by the catch mec...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.105577
更新日期:2007-07-15 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:2004-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77846-4
更新日期:1998-03-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.05.041
更新日期:2011-07-06 00:00:00
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journal_title:Biophysical journal
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:2005-11-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章,评审
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更新日期:2020-05-19 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: 信件
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更新日期:2008-01-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.112730
更新日期:2008-06-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77751-3
更新日期:1998-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)70065-4
更新日期:2003-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.113241
更新日期:2008-06-01 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:1974-06-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.06.007
更新日期:2020-07-21 00:00:00
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journal_title:Biophysical journal
pub_type: 信件
doi:10.1529/biophysj.107.120261
更新日期:2008-02-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.03.025
更新日期:2010-06-16 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:2007-06-01 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:2010-12-01 00:00:00
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journal_title:Biophysical journal
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更新日期:2006-08-01 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:1972-08-01 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:1980-12-01 00:00:00
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pub_type: 杂志文章
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更新日期:2013-07-16 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:2005-08-01 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:2003-03-01 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
doi:10.1016/S0006-3495(81)84724-8
更新日期:1981-10-01 00:00:00