The contribution of polar group burial to protein stability is strongly context-dependent.


Abstract

We previously suggested that proteins gain more stability from the burial and hydrogen bonding of polar groups than from the burial of nonpolar groups (Pace, C. N. (2001) Biochemistry 40, 310-313). To study this further, we prepared eight Thr-to-Val mutants of RNase Sa, four in which the Thr side chain is hydrogen-bonded and four in which it is not. We measured the stability of these mutants by analyzing their thermal denaturation curves. The four hydrogen-bonded Thr side chains contribute 1.3 +/- 0.9 kcal/mol to the stability; those that are not still contribute 0.4 +/- 0.9 kcal/mol to the stability. For 40 Thr-to-Val mutants of 11 proteins, the average decrease in stability is 1.0 +/- 1.0 kcal/mol when the Thr side chain is hydrogen-bonded and 0.0 +/- 0.5 kcal/mol when it is not. This is clear evidence that hydrogen bonds contribute favorably to protein stability. In addition, we prepared four Val-to-Thr mutants of RNase Sa, measured their stability, and determined their crystal structures. In all cases, the mutants are less stable than the wild-type protein, with the decreases in stability ranging from 0.5 to 4.4 kcal/mol. For 41 Val-to-Thr mutants of 11 proteins, the average decrease in stability is 1.8 +/- 1.3 kcal/mol and is unfavorable for 40 of 41 mutants. This shows that placing an [bond]OH group at a site designed for a [bond]CH3 group is very unfavorable. So, [bond]OH groups can contribute favorably to protein stability, even if they are not hydrogen-bonded, if the site was selected for an [bond]OH group, but they will make an unfavorable contribution to stability, even if they are hydrogen-bonded, when they are placed at a site selected for a [bond]CH3 group. The contribution that polar groups make to protein stability depends strongly on their environment. Study holds ProTherm entries: 16637, 16638, 16639, 16640, 16641, 16642, 16643, 16644, 16645, 16646, 16647, 16648, 16649, 16650, 16651, 16652, 16653, 16654, 16655, 16656, 16657, 16658, 16659, 16660, 16661 Extra Details: hydrogen bonding; polar groups; protein stability; environment

Submission Details

ID: n98xFrwr

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:48 p.m.

Version: 1

Publication Details
Takano K;Scholtz JM;Sacchettini JC;Pace CN,J. Biol. Chem. (2003) The contribution of polar group burial to protein stability is strongly context-dependent. PMID:12799387
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 PDB Entries

Structure ID Release Date Resolution Structure Title
1AY7 1997-11-14T00:00:00+0000 1.7 RIBONUCLEASE SA COMPLEX WITH BARSTAR
1BOX 1998-08-07T00:00:00+0000 1.6 N39S MUTANT OF RNASE SA FROM STREPTOMYCES AUREOFACIENS
1C54 1999-10-22T00:00:00+0000 0 SOLUTION STRUCTURE OF RIBONUCLEASE SA
1GMP 1992-10-01T00:00:00+0000 1.7 COMPLEX OF RIBONUCLEASE FROM STREPTOMYCES AUREOFACIENS WITH 2'-GMP AT 1.7 ANGSTROMS RESOLUTION
1GMQ 1992-10-01T00:00:00+0000 1.8 COMPLEX OF RIBONUCLEASE FROM STREPTOMYCES AUREOFACIENS WITH 2'-GMP AT 1.7 ANGSTROMS RESOLUTION
1GMR 1992-10-01T00:00:00+0000 1.77 COMPLEX OF RIBONUCLEASE FROM STREPTOMYCES AUREOFACIENS WITH 2'-GMP AT 1.7 ANGSTROMS RESOLUTION
1I70 2001-03-07T00:00:00+0000 1.7 CRYSTAL STRUCTURE OF RNASE SA Y86F MUTANT
1I8V 2001-03-16T00:00:00+0000 1.25 CRYSTAL STRUCTURE OF RNASE SA Y80F MUTANT
1LNI 2002-05-03T00:00:00+0000 1.0 CRYSTAL STRUCTURE ANALYSIS OF A RIBONUCLEASE FROM STREPTOMYCES AUREOFACIENS AT ATOMIC RESOLUTION (1.0 A)
1RGE 1995-06-05T00:00:00+0000 1.15 HYDROLASE, GUANYLORIBONUCLEASE

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Guanyl-specific ribonuclease Sa P05798 RNSA_KITAU