3qvt

L-myo-inositol 1-phosphate synthase from Archaeoglobus fulgidus wild-type with the intermediate 5-keto 1-phospho glucoseL-myo-inositol 1-phosphate synthase from Archaeoglobus fulgidus wild-type with the intermediate 5-keto 1-phospho glucose

Structural highlights 3qvt is a 1 chain structure with sequence from Archaeoglobus fulgidus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2Å Ligands: , , , , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function O28480_ARCFU Publication Abstract from PubMed 1-L-myo-inositol-phosphate synthase (mIPS) catalyzes the first step of the unique, de novo pathway of inositol biosynthesis. However, details about the complex mIPS catalytic mechanism, which requires oxidation, enolization, intramolecular aldol cyclization, and reduction, are not fully known. To gain further insight into this mechanism, we determined the crystal structure of the wild-type mIPS from Archaeoglobus fulgidus at 1.7 A, as well as the crystal structures of three active-site mutants. Additionally, we obtained the structure of mIPS with a trapped 5-keto-glucose-6-phosphate intermediate at 2 A resolution by a novel (to our knowledge) process of activating the crystal at high temperature. A comparison of all of the crystal structures of mIPS described in this work suggests a novel type of catalytic mechanism that relies on the forced atomic proximity of functional groups. The lysine cluster is contained in a small volume in the active site, where random motions of these side chains are responsible for the progress of the complex multistep reaction as well as for the low rate of catalysis. The mechanism requires that functional groups of Lys-274, Lys-278, Lys-306, and Lys-367 assume differential roles in the protonation/deprotonation steps that must occur during the mIPS reaction. This mechanism is supported by the complete loss of activity of the enzyme caused by the Leu-257 mutation to Ala that releases the lysine containment. Crystal structure of a trapped catalytic intermediate suggests that forced atomic proximity drives the catalysis of mIPS.,Neelon K, Roberts MF, Stec B Biophys J. 2011 Dec 7;101(11):2816-24. PMID:22261071 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 3qvt, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image