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On the complexation of proteins and polyelectrolytes

da Silva, FLB ; Lund, Mikael LU orcid ; Jönsson, Bo LU and Åkesson, Torbjörn LU (2006) In The Journal of Physical Chemistry Part B 110(9). p.4459-4464
Abstract
Both natural and synthetic polyelectrolytes form strong complexes with a variety of proteins. One peculiar phenomenon is that association can take place even when the protein and the polyelectrolyte carry the same charge. This has been interpreted as if the ion-dipole interaction can overcome the repulsive ion-ion interaction. On the basis of Monte Carlo simulations and perturbation theory, we propose a different explanation for the association, namely, charge regulation. We have investigated three different protein-polymer complexes and found that the induced ionization of amino acid residues due to the polyelectrolyte leads to a surprisingly strong attractive interaction between the protein and the polymer. The extra attraction from this... (More)
Both natural and synthetic polyelectrolytes form strong complexes with a variety of proteins. One peculiar phenomenon is that association can take place even when the protein and the polyelectrolyte carry the same charge. This has been interpreted as if the ion-dipole interaction can overcome the repulsive ion-ion interaction. On the basis of Monte Carlo simulations and perturbation theory, we propose a different explanation for the association, namely, charge regulation. We have investigated three different protein-polymer complexes and found that the induced ionization of amino acid residues due to the polyelectrolyte leads to a surprisingly strong attractive interaction between the protein and the polymer. The extra attraction from this charge-induced charge interaction can be several kT and is for the three cases studied here, lysozyme, alpha-lactalbumin, and beta-lactoglobulin, of the same magnitude or stronger than the ion-dipole interaction. The magnitude of the induced charge is governed by a response function, the protein charge capacitance < Z(2)> - < Z >(2). This fluctuation term can easily be calculated in a simulation or measured in a titration experiment. (Less)
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author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
The Journal of Physical Chemistry Part B
volume
110
issue
9
pages
4459 - 4464
publisher
The American Chemical Society (ACS)
external identifiers
  • wos:000235944500089
  • scopus:33645693842
  • pmid:16509749
ISSN
1520-5207
DOI
10.1021/jp054880l
language
English
LU publication?
yes
additional info
The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)
id
86900078-e09b-4192-9e9e-7bc302d8e8a8 (old id 416396)
date added to LUP
2016-04-01 15:51:40
date last changed
2023-01-04 19:40:12
@article{86900078-e09b-4192-9e9e-7bc302d8e8a8,
  abstract     = {{Both natural and synthetic polyelectrolytes form strong complexes with a variety of proteins. One peculiar phenomenon is that association can take place even when the protein and the polyelectrolyte carry the same charge. This has been interpreted as if the ion-dipole interaction can overcome the repulsive ion-ion interaction. On the basis of Monte Carlo simulations and perturbation theory, we propose a different explanation for the association, namely, charge regulation. We have investigated three different protein-polymer complexes and found that the induced ionization of amino acid residues due to the polyelectrolyte leads to a surprisingly strong attractive interaction between the protein and the polymer. The extra attraction from this charge-induced charge interaction can be several kT and is for the three cases studied here, lysozyme, alpha-lactalbumin, and beta-lactoglobulin, of the same magnitude or stronger than the ion-dipole interaction. The magnitude of the induced charge is governed by a response function, the protein charge capacitance &lt; Z(2)&gt; - &lt; Z &gt;(2). This fluctuation term can easily be calculated in a simulation or measured in a titration experiment.}},
  author       = {{da Silva, FLB and Lund, Mikael and Jönsson, Bo and Åkesson, Torbjörn}},
  issn         = {{1520-5207}},
  language     = {{eng}},
  number       = {{9}},
  pages        = {{4459--4464}},
  publisher    = {{The American Chemical Society (ACS)}},
  series       = {{The Journal of Physical Chemistry Part B}},
  title        = {{On the complexation of proteins and polyelectrolytes}},
  url          = {{http://dx.doi.org/10.1021/jp054880l}},
  doi          = {{10.1021/jp054880l}},
  volume       = {{110}},
  year         = {{2006}},
}