Advanced

Protein self-association in solution: the bovine beta-lactoglobulin dimer and octamer

Gottschalk, Michael LU ; Nilsson, Hanna LU ; Roos, Helena and Halle, Bertil LU (2003) In Protein Science 12(11). p.2404-2411
Abstract
We have used proton magnetic relaxation dispersion (MRD) to study the self-association of bovine ß-lactoglobulin variant A (BLG-A) as a function of temperature at pH 4.7 (dimer–octamer equilibrium) and as a function of NaCl concentration at pH 2.5 (monomer–dimer equilibrium). The MRD method identifies coexisting oligomers from their rotational correlation times and determines their relative populations from the associated dispersion amplitudes. From MRD-derived correlation times and hydrodynamic model calculations, we confirm that BLG-A dimers associate to octamers below room temperature. The tendency for BLG-A dimers to assemble into octamers is found to be considerably weaker than in previous light scattering studies in the presence of... (More)
We have used proton magnetic relaxation dispersion (MRD) to study the self-association of bovine ß-lactoglobulin variant A (BLG-A) as a function of temperature at pH 4.7 (dimer–octamer equilibrium) and as a function of NaCl concentration at pH 2.5 (monomer–dimer equilibrium). The MRD method identifies coexisting oligomers from their rotational correlation times and determines their relative populations from the associated dispersion amplitudes. From MRD-derived correlation times and hydrodynamic model calculations, we confirm that BLG-A dimers associate to octamers below room temperature. The tendency for BLG-A dimers to assemble into octamers is found to be considerably weaker than in previous light scattering studies in the presence of buffer salt. At pH 2.5, the MRD data are consistent with an essentially complete transition from monomers in the absence of salt to dimers in 1 M NaCl. Because of an interfering relaxation dispersion from nanosecond water exchange, we cannot determine the oligomer populations at intermediate salt concentrations. This nanosecond dispersion may reflect intersite exchange of water molecules trapped inside the large binding cavity of BLG-A. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Protein Science
volume
12
issue
11
pages
2404 - 2411
publisher
The Protein Society
external identifiers
  • wos:000186333800002
  • pmid:14573854
  • scopus:0042532737
ISSN
1469-896X
DOI
10.1110/ps.0305903
language
English
LU publication?
yes
id
0dfa176f-c4db-4561-8d36-3770e9f1bde1 (old id 128034)
date added to LUP
2007-06-29 10:06:24
date last changed
2018-08-26 03:32:48
@article{0dfa176f-c4db-4561-8d36-3770e9f1bde1,
  abstract     = {We have used proton magnetic relaxation dispersion (MRD) to study the self-association of bovine ß-lactoglobulin variant A (BLG-A) as a function of temperature at pH 4.7 (dimer–octamer equilibrium) and as a function of NaCl concentration at pH 2.5 (monomer–dimer equilibrium). The MRD method identifies coexisting oligomers from their rotational correlation times and determines their relative populations from the associated dispersion amplitudes. From MRD-derived correlation times and hydrodynamic model calculations, we confirm that BLG-A dimers associate to octamers below room temperature. The tendency for BLG-A dimers to assemble into octamers is found to be considerably weaker than in previous light scattering studies in the presence of buffer salt. At pH 2.5, the MRD data are consistent with an essentially complete transition from monomers in the absence of salt to dimers in 1 M NaCl. Because of an interfering relaxation dispersion from nanosecond water exchange, we cannot determine the oligomer populations at intermediate salt concentrations. This nanosecond dispersion may reflect intersite exchange of water molecules trapped inside the large binding cavity of BLG-A.},
  author       = {Gottschalk, Michael and Nilsson, Hanna and Roos, Helena and Halle, Bertil},
  issn         = {1469-896X},
  language     = {eng},
  number       = {11},
  pages        = {2404--2411},
  publisher    = {The Protein Society},
  series       = {Protein Science},
  title        = {Protein self-association in solution: the bovine beta-lactoglobulin dimer and octamer},
  url          = {http://dx.doi.org/10.1110/ps.0305903},
  volume       = {12},
  year         = {2003},
}