This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1jki
From Proteopedia
|
myo-Inositol-1-phosphate Synthase Complexed with an Inhibitor, 2-deoxy-glucitol-6-phosphate
Overview
1-l-myo-Inositol-1-phosphate synthase catalyzes the conversion of d-glucose 6-phosphate to 1-l-myo-inositol-1-phosphate (MIP), the first and rate-limiting step in the biosynthesis of all inositol-containing compounds. It involves an oxidation, intramolecular aldol cyclization, and reduction. We have determined the first crystal structure of MIP synthase. We present structures of both the NAD-bound enzyme and the enzyme bound to an inhibitor, 2-deoxy-glucitol-6-phosphate. While 58 amino acids are disordered in the unbound form of the enzyme in the vicinity of the active site, the inhibitor nucleates the folding of this domain in a striking example of induced fit, serving to completely encapsulate it within the enzyme. Three helices and a long beta-strand are formed in this process. We postulate a mechanism for the conversion based on the structure of the inhibitor-bound complex.
About this Structure
1JKI is a Single protein structure of sequence from Saccharomyces cerevisiae with , and as ligands. Active as Inositol-3-phosphate synthase, with EC number 5.5.1.4 Full crystallographic information is available from OCA.
Reference
The crystal structure and mechanism of 1-L-myo-inositol- 1-phosphate synthase., Stein AJ, Geiger JH, J Biol Chem. 2002 Mar 15;277(11):9484-91. Epub 2002 Jan 4. PMID:11779862
Page seeded by OCA on Thu Feb 21 13:23:38 2008
