EC Number   |
|---|
   2.7.7.74 | crystal structure of the enzyme in the apo form is solved to a 1.9 A resolution. The structure of IPCT is composed of a central seven-stranded mixed beta-sheet, of which six beta-strands are parallel, surrounded by six alpha-helices, a fold reminiscent of the dinucleotide-binding Rossmann fold |
| 2.7.7.74 | crystallization of the CTP:inositol-1-phosphate cytidylyltransferase domain in the apo form. The crystals diffracted to 2.4 A resolution using a synchrotron source and belong to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 154.7, b = 83.9, c = 127.7 A |
| 2.7.7.74 | hanging-drop vapor diffusion method at 20°C, X-ray structure of the cytoplasmic CTP:inositol-1-phosphate cytidylyltransferase domain of the bifunctional enzyme (EC 2.7.7.74/EC 2.7.8.34). The structure of the enzyme in the apo form was solved to a 1.9 A resolution. The structure of CTP:inositol-1-phosphate cytidylyltransferase is composed of a central seven-stranded mixed beta-sheet, of which six beta-strands are parallel, surrounded by six alpha-helices, a fold reminiscent of the dinucleotide-binding Rossmann fold |
| 2.7.7.74 | structure shows a conserved motif of sugar nucleotide transferases (COG1213) with a structurally reinforced C-terminal Cys bonded to the core of the protein. During catalysis, the conserved Asp107 serves as an electrostatic anchor to which the metal ion (most likely Mg2+) binds. Upon binding, the triphosphate group of the nucleotide interacts with a metal ion as well as the phosphate of the inositol. The O atom of the inositol phosphate group that is polarized by this interaction attacks the triphosphate and causes its cleavage to release the diphosphate group. Lys24 stabilizes the developing negative charge in the transition state and Arg14 serves as a release agent |
