1vj5
From Proteopedia
Human soluble Epoxide Hydrolase- N-cyclohexyl-N'-(4-iodophenyl)urea complex
Structural highlights
Function[HYES_HUMAN] Bifunctional enzyme. The C-terminal domain has epoxide hydrolase activity and acts on epoxides (alkene oxides, oxiranes) and arene oxides. Plays a role in xenobiotic metabolism by degrading potentially toxic epoxides. Also determines steady-state levels of physiological mediators. The N-terminal domain has lipid phosphatase activity, with the highest activity towards threo-9,10-phosphonooxy-hydroxy-octadecanoic acid, followed by erythro-9,10-phosphonooxy-hydroxy-octadecanoic acid, 12-phosphonooxy-octadec-9Z-enoic acid, 12-phosphonooxy-octadec-9E-enoic acid, and p-nitrophenyl phospate.[1] [2] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe X-ray crystal structure of human soluble epoxide hydrolase (sEH) has been determined at 2.6 A resolution, revealing a domain-swapped quaternary structure identical to that observed for the murine enzyme [Argiriadi, M. A., Morisseau, C., Hammock, B. D., and Christianson, D. W. (1999) Proc. Natl. Acad. Sci. U.S.A. 96, 10637-10642]. As with the murine enzyme, the epoxide hydrolytic mechanism of the human enzyme proceeds through an alkyl-enzyme intermediate with Asp-333 in the C-terminal domain. The structure of the human sEH complex with N-cyclohexyl-N'-(iodophenyl)urea (CIU) has been determined at 2.35 A resolution. Tyr-381 and Tyr-465 donate hydrogen bonds to the alkylurea carbonyl group of CIU, consistent with the proposed roles of these residues as proton donors in the first step of catalysis. The N-terminal domain of mammalian sEH contains a 15 A deep cleft, but its biological function is unclear. Recent experiments demonstrate that the N-terminal domain of human sEH catalyzes the metal-dependent hydrolysis of phosphate esters [Cronin, A., Mowbray, S., Durk, H., Homburg, S., Fleming, I., Fisslthaler, B., Oesch, F., and Arand, M. (2003) Proc. Natl. Acad. Sci. U.S.A. 100, 1552-1557; Newman, J. W., Morisseau, C., Harris, T. R., and Hammock, B. D. (2003) Proc. Natl. Acad. Sci. U.S.A. 100, 1558-1563]. The binding of Mg(2+)-HPO4(2-) to the N-terminal domain of human sEH in its CIU complex reveals structural features relevant to those of the enzyme-substrate complex in the phosphatase reaction. Structure of human epoxide hydrolase reveals mechanistic inferences on bifunctional catalysis in epoxide and phosphate ester hydrolysis.,Gomez GA, Morisseau C, Hammock BD, Christianson DW Biochemistry. 2004 Apr 27;43(16):4716-23. PMID:15096040[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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