Evidence map›Paper›PMID 21081085›Full record

ArticleBiophysical journal2010

pK(a) values for the unfolded state under native conditions explain the pH-dependent stability of PGB1.

Stina Lindman, Mikael C Bauer, Mikael Lund, Carl Diehl, Frans A A Mulder, Mikael Akke, Sara Linse

Abstract read
In one paragraph

Article in Biophysical journal, 2010. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed.

  1. Comparative Performance of High-Throughput Methods for Protein pJournal of chemical information and modeling · 2023
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Stina LindmanCenter for Molecular Protein Science, Lund University, Lund, Sweden.
Mikael C Bauer
Mikael Lund
Carl Diehl
Frans A A Mulder
Mikael Akke
Sara Linse

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Understanding the role of electrostatics in protein stability requires knowledge of these interactions in both the folded and unfolded states. Electrostatic interactions can be probed experimentally by characterizing ionization equilibria of titrating groups, parameterized as pK(a) values. However, pK(a) values of the unfolded state are rarely accessible under native conditions, where the unfolded state has a very low population. Here, we report pK(a) values under nondenaturing conditions for two unfolded fragments of the protein G B1 domain that mimic the unfolded state of the intact protein. pK(a) values were determined for carboxyl groups by monitoring their pH-dependent (13)C chemical shifts. Monte Carlo simulations using a Gaussian chain model provide corrections for changes in electrostatic interactions that arise from fragmentation of the protein. Most pK(a) values for the unfolded state agree well with model values, but some residues show significant perturbations that can be rationalized by local electrostatic interactions. The pH-dependent stability was calculated from the experimental pK(a) values of the folded and unfolded states and compared to experimental stability data. The use of experimental pK(a) values for the unfolded state results in significantly improved agreement with experimental data, as compared to calculations based on model data alone.

Indexed as

Protein UnfoldingAmino AcidsAmino Acid SequenceBacterial ProteinsHydrogen-Ion ConcentrationMolecular Dynamics SimulationMolecular Sequence DataMutant ProteinsNuclear Magnetic Resonance, BiomolecularProtein StabilityProtein Structure, TertiaryProtonsThermodynamicsTitrimetryAmino AcidsBacterial ProteinsIgG Fc-binding protein, StreptococcusMutant ProteinsProtons

Identifiers

PMID21081085
PMCPMC2980744

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.