Journal article
Increasing protein stability: Importance of Delta C-p and the denatured state
Protein science, Vol.19(5), pp.1044-1052
05/01/2010
DOI: 10.1002/pro.381
PMCID: PMC2868246
PMID: 20340133
Abstract
Increasing the conformational stability of proteins is an important goal for both basic research and industrial applications. In vitro selection has been used successfully to increase protein stability, but more often site-directed mutagenesis is used to optimize the various forces that contribute to protein stability. In previous studies, we showed that improving electrostatic interactions on the protein surface and improving the beta-turn sequences were good general strategies for increasing protein stability, and used them to increase the stability of RNase Sa. By incorporating seven of these mutations in RNase Sa, we increased the stability by 5.3 kcal/mol. Adding one more mutation, D79F, gave a total increase in stability of 7.7 kcal/mol, and a melting temperature 28 degrees C higher than the wild-type enzyme. Surprisingly, the D79F mutation lowers the change in heat capacity for folding, Delta C-p, by 0.6 kcal/mol/K. This suggests that this mutation stabilizes structure in the denatured state ensemble. We made other mutants that give some insight into the structure present in the denatured state. Finally, the thermodynamics of folding of these stabilized variants of RNase Sa are compared with those observed for proteins from thermophiles.
Details
- Title: Subtitle
- Increasing protein stability: Importance of Delta C-p and the denatured state
- Creators
- Hailong Fu - Texas A&M UniversityGerald Grimsley - Texas A&M Health Science CenterJ. Martin Scholtz - Texas A&M UniversityC. Nick Pace - Texas A&M University
- Resource Type
- Journal article
- Publication Details
- Protein science, Vol.19(5), pp.1044-1052
- DOI
- 10.1002/pro.381
- PMID
- 20340133
- PMCID
- PMC2868246
- NLM abbreviation
- Protein Sci
- ISSN
- 0961-8368
- eISSN
- 1469-896X
- Publisher
- Wiley
- Number of pages
- 9
- Grant note
- GM 37039; GM 52483 / NIH; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA BE-1060; BE-1281 / Robert A. Welch Foundation; The Welch Foundation Tom and Jean McMullin Professorship R29GM052483 / NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Institute of General Medical Sciences (NIGMS)
- Language
- English
- Date published
- 05/01/2010
- Academic Unit
- Research Administration; Pharmaceutical Sciences and Experimental Therapeutics; Biochemistry and Molecular Biology; Chemistry
- Record Identifier
- 9984288728602771
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