1j0r
From Proteopedia
Crystal structure of the replication termination protein mutant C110S
Overview
We report the structural and biophysical consequences of cysteine substitutions in the DNA-binding replication terminator protein (RTP) of Bacillus subtilis, that resulted in an optimised RTP mutant suitable for structural studies. The cysteine residue 110 was replaced with alanine, valine or serine. Protein secondary structure and stability (using circular dichroism spectropolarimetry), self-association (using analytical ultracentrifugation), and DNA-binding measurements revealed RTP.C110S to be the most similar mutant to wild-type RTP. The C110A and C110V.RTP mutants were less soluble, less stable and showed lower DNA-binding affinity. The structure of RTP.C110S, solved to 2.5A resolution using crystallographic methods, showed no major structural perturbation due to the mutation. Heteronuclear NMR spectroscopic studies revealed subtle differences in the electronic environment about the site of mutation. The study demonstrates the suitability of serine as a substitute for cysteine in RTP and the high sensitivity of protein behaviour to single amino acid substitutions.
About this Structure
1J0R is a Single protein structure of sequence from Bacillus subtilis. Full crystallographic information is available from OCA.
Reference
The impact of single cysteine residue mutations on the replication terminator protein., Vivian JP, Hastings AF, Duggin IG, Wake RG, Wilce MC, Wilce JA, Biochem Biophys Res Commun. 2003 Oct 31;310(4):1096-103. PMID:14559228 Page seeded by OCA on Fri May 2 20:39:47 2008
