Equilibrium dissociation and unfolding of the Arc repressor dimer.


Abstract

The equilibrium unfolding reaction of Arc repressor, a dimeric DNA binding protein encoded by bacteriophage P22, can be monitored by fluorescence or circular dichroism changes. The stability of Arc is concentration dependent, and the unfolding reaction is well described as a two-state transition from folded dimer to unfolded monomer. The stability of the protein is decreased at low pH and increased by high salt concentration. The salt dependence suggests that two ions bind preferentially to the folded protein. In 10 mM potassium phosphate (pH 7.3) and 100 mM KCl, the unfolding free energy reaches a maximum near room temperature. The results suggest that at the low protein concentrations where operator DNA binding is normally measured, Arc is predominantly monomeric and unfolded. Study holds ProTherm entries: 3935, 3936, 3937 Extra Details: DNA binding protein; concentration dependent;,two-state transition; low protein concentrations

Submission Details

ID: t4qPeytv

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:23 p.m.

Version: 1

Publication Details
Bowie JU;Sauer RT,Biochemistry (1989) Equilibrium dissociation and unfolding of the Arc repressor dimer. PMID:2819054
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
1QTG 1999-07-12 AVERAGED NMR MODEL OF SWITCH ARC, A DOUBLE MUTANT OF ARC REPRESSOR
1B28 1999-11-03 ARC REPRESSOR MYL MUTANT FROM SALMONELLA BACTERIOPHAGE P22
1NLA 2003-03-18 Solution Structure of Switch Arc, a Mutant with 3(10) Helices Replacing a Wild-Type Beta-Ribbon
1ARR 1994-01-31 RELAXATION MATRIX REFINEMENT OF THE SOLUTION STRUCTURE OF THE ARC REPRESSOR
1ARQ 1994-01-31 RELAXATION MATRIX REFINEMENT OF THE SOLUTION STRUCTURE OF THE ARC REPRESSOR
1BAZ 1998-06-17 1.9 ARC REPRESSOR MUTANT PHE10VAL
1U9P 2005-02-15 1.9 Permuted single-chain Arc
1MYL 1995-01-26 2.4 SUBSTITUTING HYDROPHOBIC RESIDUES FOR A BURIED SALT BRIDGE ENHANCES PROTEIN STABILITY BUT DOES NOT REDUCE CONFORMATIONAL SPECIFICITY
1MYK 1995-01-26 2.4 CRYSTAL STRUCTURE, FOLDING, AND OPERATOR BINDING OF THE HYPERSTABLE ARC REPRESSOR MUTANT PL8
1BDT 1999-02-16 2.5 WILD TYPE GENE-REGULATING PROTEIN ARC/DNA COMPLEX
1PAR 1994-07-31 2.6 DNA RECOGNITION BY BETA-SHEETS IN THE ARC REPRESSOR-OPERATOR CRYSTAL STRUCTURE
1BDV 1999-01-06 2.8 ARC FV10 COCRYSTAL

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Transcriptional repressor arc P03050 RARC_BPP22