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High-Efficiency Expression and Purification of DNAJB6b Based on the pH-Modulation of Solubility and Denaturant-Modulation of Size

Linse, Sara LU (2022) In Molecules 27(2).
Abstract

The chaperone DNAJB6b delays amyloid formation by suppressing the nucleation of amyloid fibrils and increases the solubility of amyloid-prone proteins. These dual effects on kinetics and equilibrium are related to the unusually high chemical potential of DNAJB6b in solution. As a consequence, the chaperone alone forms highly polydisperse oligomers, whereas in a mixture with an amyloid-forming protein or peptide it may form co-aggregates to gain a reduced chemical potential, thus enabling the amyloid peptide to increase its chemical potential leading to enhanced solubility of the peptide. Understanding such action at the level of molecular driving forces and detailed structures requires access to highly pure and sequence homogeneous... (More)

The chaperone DNAJB6b delays amyloid formation by suppressing the nucleation of amyloid fibrils and increases the solubility of amyloid-prone proteins. These dual effects on kinetics and equilibrium are related to the unusually high chemical potential of DNAJB6b in solution. As a consequence, the chaperone alone forms highly polydisperse oligomers, whereas in a mixture with an amyloid-forming protein or peptide it may form co-aggregates to gain a reduced chemical potential, thus enabling the amyloid peptide to increase its chemical potential leading to enhanced solubility of the peptide. Understanding such action at the level of molecular driving forces and detailed structures requires access to highly pure and sequence homogeneous DNAJB6b with no sequence extension. We therefore outline here an expression and purification protocol of the protein “as is” with no tags leading to very high levels of pure protein based on its physicochemical properties, including size and charge. The versatility of the protocol is demonstrated through the expression of an isotope labelled protein and seven variants, and the purification of three of these. The activity of the protein is bench-marked using aggregation assays. Two of the variants are used to produce a palette of fluorescent DNAJB6b labelled at an engineered N-or C-terminal cysteine.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Extraction, Self-assembly, Solubilization
in
Molecules
volume
27
issue
2
article number
418
publisher
MDPI AG
external identifiers
  • pmid:35056736
  • scopus:85122535648
ISSN
1420-3049
DOI
10.3390/molecules27020418
language
English
LU publication?
yes
additional info
Publisher Copyright: © 2022 by the author. Licensee MDPI, Basel, Switzerland.
id
890d79b9-5979-4efb-a4fe-dd4582d9ec0a
date added to LUP
2022-02-11 16:19:32
date last changed
2024-05-07 23:23:03
@article{890d79b9-5979-4efb-a4fe-dd4582d9ec0a,
  abstract     = {{<p>The chaperone DNAJB6b delays amyloid formation by suppressing the nucleation of amyloid fibrils and increases the solubility of amyloid-prone proteins. These dual effects on kinetics and equilibrium are related to the unusually high chemical potential of DNAJB6b in solution. As a consequence, the chaperone alone forms highly polydisperse oligomers, whereas in a mixture with an amyloid-forming protein or peptide it may form co-aggregates to gain a reduced chemical potential, thus enabling the amyloid peptide to increase its chemical potential leading to enhanced solubility of the peptide. Understanding such action at the level of molecular driving forces and detailed structures requires access to highly pure and sequence homogeneous DNAJB6b with no sequence extension. We therefore outline here an expression and purification protocol of the protein “as is” with no tags leading to very high levels of pure protein based on its physicochemical properties, including size and charge. The versatility of the protocol is demonstrated through the expression of an isotope labelled protein and seven variants, and the purification of three of these. The activity of the protein is bench-marked using aggregation assays. Two of the variants are used to produce a palette of fluorescent DNAJB6b labelled at an engineered N-or C-terminal cysteine.</p>}},
  author       = {{Linse, Sara}},
  issn         = {{1420-3049}},
  keywords     = {{Extraction; Self-assembly; Solubilization}},
  language     = {{eng}},
  month        = {{01}},
  number       = {{2}},
  publisher    = {{MDPI AG}},
  series       = {{Molecules}},
  title        = {{High-Efficiency Expression and Purification of DNAJB6b Based on the pH-Modulation of Solubility and Denaturant-Modulation of Size}},
  url          = {{http://dx.doi.org/10.3390/molecules27020418}},
  doi          = {{10.3390/molecules27020418}},
  volume       = {{27}},
  year         = {{2022}},
}