The effects of ionic strength on protein stability: the cold shock protein family.


Continuum electrostatic models are used to examine in detail the mechanism of protein stabilization and destabilization due to salt near physiological concentrations. Three wild-type cold shock proteins taken from mesophilic, thermophilic, and hyperthermophilic bacteria are studied using these methods. The model is validated by comparison with experimental data collected for these proteins. In addition, a number of single point mutants and three designed sequences are examined. The results from this study demonstrate that the sensitivity of protein stability toward salt is correlated with thermostability in the cold shock protein family. The calculations indicate that the mesophile is stabilized by the presence of salt while the thermophile and hyperthermophile are destabilized. A decomposition of the salt influence at a residue level permits identification of regions of the protein sequences that contribute toward the observed salt-dependent stability. This model is used to rationalize the effect of various point mutations with regard to sensitivity toward salt. Finally, it is demonstrated that designed cold shock protein variants exhibit electrostatic properties similar to the natural thermophilic and hyperthermophilic proteins. Study holds ProTherm entries: 15240, 15241, 15242, 15243, 15244, 15245, 15246, 15247 Extra Details: delta Cp is 4 kJ/mol/K protein folding; electrostatics; salt effects; cold shock proteins; thermophilic proteins

Submission Details

ID: 37srEhfc

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:46 p.m.

Version: 1

Publication Details
Dominy BN;Perl D;Schmid FX;Brooks CL,J. Mol. Biol. (2002) The effects of ionic strength on protein stability: the cold shock protein family. PMID:12051927
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Cold shock protein CspB P32081 CSPB_BACSU
92.3 Cold shock protein CspB Q81K90 CSPD_BACAN
92.3 Cold shock protein CspB Q816H3 CSPD_BACCR
96.5 Cold shock protein CspB P41018 CSPB_SPOGL
100.0 Cold shock protein CspB P41016 CSPB_BACCL
98.5 Cold shock protein CspB P42016 CSPB_GEOSE