4jd0

Structure of the inositol-1-phosphate CTP transferase from T. maritima.Structure of the inositol-1-phosphate CTP transferase from T. maritima.

Structural highlights 4jd0 is a 1 chain structure with sequence from Thermotoga maritima MSB8. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.8Å Ligands: , , , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed The unique steps in the synthesis of an unusual osmolyte in hyperthermophiles, di-myo-inositol-1,1'-phosphate (DIP), involve the production of CDP-inositol and its condensation with an inositol-1-phosphate molecule to form phosphorylated DIP. While many organisms fuse both activities into a single enzyme, the two are separate in Thermotoga maritima. The crystal structure of the T. maritima inositol-1-phosphate cytidylyltransferase, which as a soluble protein may transiently associate with its membrane-embedded partner phospho-DIP synthase (P-DIPS), has now been obtained. The structure shows a conserved motif of sugar nucleotide transferases (COG1213) with a structurally reinforced C-terminal Cys bonded to the core of the protein. A bound arsenosugar identifies the location of the active site for inositol 1-phosphate. Based on homologous structures from several species and the identification of the crucial conserved aspartate residue, a catalytic mechanism for this enzyme is proposed as well as a mode for its association with P-DIPS. This structure imposes constraints on the mode of association, communication and temperature activation of two separate enzymes in T. maritima. For the first time, a working model for the membrane-bound P-DIPS unit has been constructed. This sheds light on the functioning of the phosphatidylserine and phosphatidylinositol synthases involved in many physiological processes that are homologous to P-DIPS. This work provides fresh insights into the synthesis of the unusual thermoprotective compound DIP in hyperthermophiles. Structure of the inositol-1-phosphate cytidylyltransferase from Thermotoga maritima.,Kurnasov OV, Luk HJ, Roberts MF, Stec B Acta Crystallogr D Biol Crystallogr. 2013 Sep 1;69(Pt 9):1808-17. doi:, 10.1107/S0907444913015278. Epub 2013 Aug 17. PMID:23999304 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4jd0, resolution 1.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image