Charge Interactions in a Highly Charge-Depleted Protein
(2021) In Journal of the American Chemical Society 143(6). p.2500-2508- Abstract
Electrostatic forces are important for protein folding and are favored targets of protein engineering. However, interactions between charged residues are difficult to study because of the complex network of interactions found in most proteins. We have designed a purposely simple system to investigate this problem by systematically introducing individual and pairs of charged and titratable residues in a protein otherwise free of such residues. We used constant pH molecular dynamics simulations, NMR spectroscopy, and thermodynamic double mutant cycles to probe the structure and energetics of the interaction between the charged residues. We found that the partial burial of surface charges contributes to a shift in pKa value, causing an... (More)
Electrostatic forces are important for protein folding and are favored targets of protein engineering. However, interactions between charged residues are difficult to study because of the complex network of interactions found in most proteins. We have designed a purposely simple system to investigate this problem by systematically introducing individual and pairs of charged and titratable residues in a protein otherwise free of such residues. We used constant pH molecular dynamics simulations, NMR spectroscopy, and thermodynamic double mutant cycles to probe the structure and energetics of the interaction between the charged residues. We found that the partial burial of surface charges contributes to a shift in pKa value, causing an aspartate to titrate in the neutral pH range. Additionally, the interaction between pairs of residues was found to be highly context dependent, with some pairs having no apparent preferential interaction, while other pairs would engage in coupled titration forming a highly stabilized salt bridge. We find good agreement between experiments and simulations and use the simulations to rationalize our observations and to provide a detailed mechanistic understanding of the electrostatic interactions.
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- author
- Hervø-Hansen, Stefan LU ; Højgaard, Casper ; Johansson, Kristoffer Enøe ; Wang, Yong ; Wahni, Khadija ; Young, David ; Messens, Joris ; Teilum, Kaare LU ; Lindorff-Larsen, Kresten and Winther, Jakob Rahr
- organization
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of the American Chemical Society
- volume
- 143
- issue
- 6
- pages
- 2500 - 2508
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85100628328
- pmid:33529004
- ISSN
- 0002-7863
- DOI
- 10.1021/jacs.0c10789
- language
- English
- LU publication?
- yes
- id
- 3bee2b9f-ff5e-4c85-a192-1e4a9a24c152
- date added to LUP
- 2021-02-26 09:19:58
- date last changed
- 2024-08-22 14:40:40
@article{3bee2b9f-ff5e-4c85-a192-1e4a9a24c152,
abstract = {{<p>Electrostatic forces are important for protein folding and are favored targets of protein engineering. However, interactions between charged residues are difficult to study because of the complex network of interactions found in most proteins. We have designed a purposely simple system to investigate this problem by systematically introducing individual and pairs of charged and titratable residues in a protein otherwise free of such residues. We used constant pH molecular dynamics simulations, NMR spectroscopy, and thermodynamic double mutant cycles to probe the structure and energetics of the interaction between the charged residues. We found that the partial burial of surface charges contributes to a shift in pKa value, causing an aspartate to titrate in the neutral pH range. Additionally, the interaction between pairs of residues was found to be highly context dependent, with some pairs having no apparent preferential interaction, while other pairs would engage in coupled titration forming a highly stabilized salt bridge. We find good agreement between experiments and simulations and use the simulations to rationalize our observations and to provide a detailed mechanistic understanding of the electrostatic interactions. </p>}},
author = {{Hervø-Hansen, Stefan and Højgaard, Casper and Johansson, Kristoffer Enøe and Wang, Yong and Wahni, Khadija and Young, David and Messens, Joris and Teilum, Kaare and Lindorff-Larsen, Kresten and Winther, Jakob Rahr}},
issn = {{0002-7863}},
language = {{eng}},
number = {{6}},
pages = {{2500--2508}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Journal of the American Chemical Society}},
title = {{Charge Interactions in a Highly Charge-Depleted Protein}},
url = {{http://dx.doi.org/10.1021/jacs.0c10789}},
doi = {{10.1021/jacs.0c10789}},
volume = {{143}},
year = {{2021}},
}