Structural and energetic consequences of disruptive mutations in a protein core.


Abstract

We have characterized the properties of a set of variants of the N-terminal domain of lambda repressor bearing disruptive mutations in the hydrophobic core. These mutations include some that dramatically alter the total core residue volume (by up to six methylene groups) and some that place a single polar residue into the otherwise hydrophobic core. The structural properties of the purified proteins have been studied by CD spectroscopy, biological activity, recognition by conformation-specific monoclonal antibodies, and 1H NMR spectroscopy. The stabilities of the proteins have been measured by thermal and guanidine hydrochloride denaturation. Proteins with disruptive core mutations are found to display a continuum of increasingly nonnative properties. Large internal volume changes cause both significant conformational rearrangements and destabilization by up to 5 kcal/mol. Variants with polar substitutions at core positions no longer behave like well-folded proteins but rather display characteristics of molten globules. However, even proteins bearing some of the most disruptive mutations retain many of the crude secondary and tertiary structural features of the wild-type protein. These results indicate that primitive elements of native structure can form in the absence of normal core packing. Study holds ProTherm entries: 207, 208, 209, 210, 211, 212, 213, 214, 215, 2170, 2171, 2172, 2173, 2174, 2175, 2176, 2177, 2178, 2179, 2180, 2181, 2182, 2183, 2184, 2185, 2186, 2187, 2188, 2189, 2190 Extra Details: lambda repressor; hydrophobic core; CD spectroscopy;,energetic consequences

Submission Details

ID: iA7sGA6F4

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:14 p.m.

Version: 1

Publication Details
Lim WA;Farruggio DC;Sauer RT,Biochemistry (1992) Structural and energetic consequences of disruptive mutations in a protein core. PMID:1567879
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
3KZ3 2010-02-23 1.64 A structure of a lambda repressor fragment mutant
1LMB 1991-11-05 1.8 REFINED 1.8 ANGSTROM CRYSTAL STRUCTURE OF THE LAMBDA REPRESSOR-OPERATOR COMPLEX
5ZCA 2018-08-15 1.8 Crystal structure of lambda repressor (1-20) fused with maltose-binding protein
1F39 2000-07-26 1.9 CRYSTAL STRUCTURE OF THE LAMBDA REPRESSOR C-TERMINAL DOMAIN
3WOA 2015-04-29 2.0 Crystal structure of lambda repressor (1-45) fused with maltose-binding protein
1LLI 1994-08-31 2.1 THE CRYSTAL STRUCTURE OF A MUTANT PROTEIN WITH ALTERED BUT IMPROVED HYDROPHOBIC CORE PACKING
1RIO 2004-01-27 2.3 Structure of bacteriophage lambda cI-NTD in complex with sigma-region4 of Thermus aquaticus bound to DNA
1KCA 2001-12-21 2.91 Crystal Structure of the lambda Repressor C-terminal Domain Octamer
1LRP 1989-01-09 3.2 COMPARISON OF THE STRUCTURES OF CRO AND LAMBDA REPRESSOR PROTEINS FROM BACTERIOPHAGE LAMBDA
3BDN 2008-04-15 3.91 Crystal Structure of the Lambda Repressor

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
193.4 A,B Repressor protein cI P03034 RPC1_LAMBD