2JZP image
Deposition Date 2008-01-11
Release Date 2009-01-13
Last Version Date 2024-05-29
Entry Detail
PDB ID:
2JZP
Keywords:
Title:
NMR solution structure of Kx5Q ProtL mutant
Biological Source:
Source Organism:
Host Organism:
Method Details:
Experimental Method:
Conformers Calculated:
100
Conformers Submitted:
20
Selection Criteria:
structures with the least restraint violations
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Protein L
Mutations:K23Q, K28Q, K42Q, K54Q, K61Q
Chain IDs:A
Chain Length:64
Number of Molecules:1
Biological Source:Peptostreptococcus magnus
Ligand Molecules
Primary Citation
Protein stabilization and the hofmeister effect: the role of hydrophobic solvation
Biophys.J. 97 2595 2603 (2009)
PMID: 19883603 DOI: 10.1016/j.bpj.2009.08.029

Abstact

Using the IGg binding domain of protein L from Streptoccocal magnus (ProtL) as a case study, we investigated how the anions of the Hofmeister series affect protein stability. To that end, a suite of lysine-to-glutamine modifications were obtained and structurally and thermodynamically characterized. The changes in stability introduced with the mutation are related to the solvent-accessible area of the side chain, specifically to the solvation of the nonpolar moiety of the residue. The thermostability for the set of ProtL mutants was determined in the presence of varying concentrations (0-1 M) of six sodium salts from the Hofmeister series: sulfate, phosphate, fluoride, nitrate, perchlorate, and thiocyanate. For kosmotropic anions (sulfate, phosphate, and fluoride), the stability changes induced by the cosolute (encoded in m(3)=deltaDeltaG(0)/deltaC(3)) are proportional to the surface changes introduced with the mutation. In contrast, the m(3) values measured for chaotropic anions are much more independent of such surface modifications. Our results are consistent with a model in which the increase in the solution surface tension induced by the anion stabilizes the folded conformation of the protein. This contribution complements the nonspecific and weak interactions between the ions and the protein backbone that shift the equilibrium toward the unfolded state.

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Primary Citation of related structures