Striking stabilization of Arc repressor by an engineered disulfide bond.


A solvent-exposed Cys11-Cys11' disulfide bond was designed to link the antiparallel strands of the beta sheet both in the Arc repressor dimer and in a single-chain variant in which the Arc subunits are connected by a 15-residue peptide tether. In both proteins, the presence of the disulfide bond increased the T(m) by approximately 40 degrees C. In the single-chain background, the disulfide bond stabilized Arc by 8.5 kcal/mol relative to the reduced form, a significantly larger degree of stabilization than caused by other engineered disulfides and most natural disulfides. This exceptional stabilization arises from a modest effective concentration of the Cys11-Cys11' disulfide in the native state (71 M) and an anomalously low effective concentration in the denatured state (40 microM). Disulfide cross-linking of the two beta strands in the single-chain Arc background accelerated refolding by a factor of 170 into the sub-microsecond time scale. However, the major energetic effect of the disulfide occurs after the transition state for Arc refolding, slowing unfolding by 200 000-fold. Study holds ProTherm entries: 8505, 8506 Extra Details: additive : EDTA(0.2 mM), solvent-exposed; disulfide bond; antiparallel strands; transition state

Submission Details


Submitter: Connie Wang

Submission Date: April 24, 2018, 8:36 p.m.

Version: 1

Publication Details
Robinson CR;Sauer RT,Biochemistry (2000) Striking stabilization of Arc repressor by an engineered disulfide bond. PMID:11015231
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 Transcriptional repressor arc P03050 RARC_BPP22