1cq4
From Proteopedia
CI2 MUTANT WITH TETRAGLUTAMINE (MGQQQQGM) REPLACING MET59
Overview
We have constructed mutants of chymotrypsin inhibitor 2 with short glutamine repeats inserted into its inhibitory loop. These mutants oligomerize when expressed in Escherichia coli. The dimer of a mutant with four glutamines now has been crystallized, and its structure has been solved by molecular replacement by using the wild-type monomer as a search model. The structure of each half of the dimer is found to be the same as that of the wild-type monomer, except around the glutamine insertion. It was proposed that the components of the oligomers are held together by hydrogen bonds between the main-chain and side-chain amides of the glutamine repeats. Instead, they appear to form by swapping domains on folding in E. coli, and the glutamine repeats connecting the components of the dimers are disordered.
About this Structure
1CQ4 is a Protein complex structure of sequences from Hordeum vulgare. Full crystallographic information is available from OCA.
Reference
Crystal structure of a dimeric chymotrypsin inhibitor 2 mutant containing an inserted glutamine repeat., Chen YW, Stott K, Perutz MF, Proc Natl Acad Sci U S A. 1999 Feb 16;96(4):1257-61. PMID:9990011 Page seeded by OCA on Fri May 2 12:59:39 2008
