1kte
CRYSTAL STRUCTURE OF THIOLTRANSFERASE AT 2.2 ANGSTROM RESOLUTION
|
OverviewOverview
We report here the first three-dimensional structure of a mammalian, thioltransferase as determined by single crystal X-ray crystallography at, 2.2 A resolution. The protein is known for its thiol-redox properties and, dehydroascorbate reductase activity. Recombinant pig liver, thioltransferase expressed in Escherichia coli was crystallized in its, oxidized form by vapor diffusion technique. The structure was determined, by multiple isomorphous replacement method using four heavy-atom, derivatives. The protein folds into an alpha/beta structure with a, four-stranded mixed beta-sheet in the core, flanked on either side by, helices. The fold is similar to that found in other thiol-redox proteins, viz. E. coli thioredoxin and bacteriophage T4 glutaredoxin, and thus seems, to be conserved in these functionally related proteins. The active site, disulfide (Cys 22-Cys 25) is located on a protrusion on the molecular, surface. Cys 22, which is known to have an abnormally low pKa of 3.8, is, accessible from the exterior of the molecule. Pro 70, which is in close, proximity to the disulfide bridge, assumes a conserved cis-peptide, configuration. Mutational data available on the protein are in agreement, with the three-dimensional structure.
About this StructureAbout this Structure
1KTE is a Single protein structure of sequence from Sus scrofa. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of thioltransferase at 2.2 A resolution., Katti SK, Robbins AH, Yang Y, Wells WW, Protein Sci. 1995 Oct;4(10):1998-2005. PMID:8535236
Page seeded by OCA on Tue Nov 20 19:51:09 2007