1q54

STRUCTURE AND MECHANISM OF ACTION OF ISOPENTENYLPYROPHOSPHATE-DIMETHYLALLYLPYROPHOSPHATE ISOMERASE: COMPLEX WITH THE BROMOHYDRINE OF IPP

spinqualitylabelsall models 1q54, resolution 1.93Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1q54 is a 2 chain structure with sequence from Escherichia coli. This structure supersedes the now removed PDB entry 1n2u. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.93Å Ligands: BHI, MG, MN Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function IDI_ECOLI Catalyzes the 1,3-allylic rearrangement of the homoallylic substrate isopentenyl (IPP) to its highly electrophilic allylic isomer, dimethylallyl diphosphate (DMAPP). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed We have obtained the three-dimensional X-ray crystallographic structure of a C67A mutant Escherichia coli isopentenylpyrophosphate-dimethylallylpyrophosphate isomerase (EC 5.3.3.2) complexed with the bromohydrin of isopentenylpyrophosphate, at 1.93 A resolution. The overall backbone fold is very similar to that obtained previously for the wild-type enzyme in the presence of a divalent metal cation (Mn2+ or Mg2+). However, in the new structure, there are two metal binding sites, not just one. The first metal binding site is occupied by Mn2+, coordinated to three histidine and two glutamate residues, while the second is occupied by Mg2+, coordinated to two bromohydrin-ligand phosphate oxygens, the carbonyl oxygen of A67, a carboxyl oxygen of E87, and two water molecules. The C3 hydroxyl group of the bromohydrin inhibitor is involved in a short hydrogen bond to the carboxyl group of E116, one of the two Mn-bound glutamates. The structure obtained is consistent with a mechanism of action of the enzyme in which the carboxyl group of E116 protonates the double bond in isopentenylpyrophosphate, forming a carbocation, followed by removal of a C2 proton by the thiolate of C67, in the wild-type enzyme. The inhibition of the enzyme by a wide variety of other potent inhibitors is also readily explained on the basis of the bromohydrin inhibitor structure. Structure and mechanism of action of isopentenylpyrophosphate-dimethylallylpyrophosphate isomerase.,Wouters J, Oudjama Y, Ghosh S, Stalon V, Droogmans L, Oldfield E J Am Chem Soc. 2003 Mar 19;125(11):3198-9. PMID:12630859 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Isopentenyl-diphosphate delta-isomerase

Proteopedia Page Contributors and Editors (what is this?)

OCA