PDBsum entry 4rut

Oxidoreductase

PDB id: 4rut

Contents

Protein chains

552 a.a.

Ligands

NAG-NAG ×4

NAG ×8

COH ×4

LM8 ×4

BOG ×2

Waters ×1138

PDB id:

4rut

Name:

Oxidoreductase

Title:

Crystal structure of murine cyclooxygenase-2 with 13-methyl- arachidonic acid

Structure:

Prostaglandin g/h synthase 2. Chain: a, b, c, d. Synonym: cyclooxygenase-2, cox-2, glucocorticoid-regulated inflammatory cyclooxygenase, gripghs, macrophage activation- associated marker protein p71/73, pes-2, phs ii, prostaglandin h2 synthase 2, pgh synthase 2, pghs-2, prostaglandin-endoperoxide synthase 2, tis10 protein. Engineered: yes

Source:

Mus musculus. Mouse. Organism_taxid: 10090. Gene: ptgs2, cox-2, cox2, pghs-b, tis10. Expressed in: spodoptera frugiperda. Expression_system_taxid: 7108.

Resolution:

2.16Å R-factor: 0.178 R-free: 0.224

Authors:

S.Xu,S.N.Kudalkar,S.Banerjee,A.Makriyannis,S.P.Nikas,L.J.Marnett

Key ref:

S.N.Kudalkar et al. (2015). 13-Methylarachidonic acid is a positive allosteric modulator of endocannabinoid oxygenation by cyclooxygenase. J Biol Chem, 290, 7897-7909. PubMed id: 25648895 DOI: 10.1074/jbc.M114.634014

Date:

21-Nov-14 Release date: 11-Feb-15

Protein chains

Q05769  (PGH2_MOUSE) -  Prostaglandin G/H synthase 2 from Mus musculus

Seq: 604 a.a.

Struc: 552 a.a.

Enzyme reactions

• Enzyme class: E.C.1.14.99.1 - prostaglandin-endoperoxide synthase.
• Reaction: (5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 O2 = prostaglandin H2 + A + H2O

(5Z,8Z,11Z,14Z)-eicosatetraenoate + AH2 + 2 × O2 = prostaglandin H2 + + H2O (Bound ligand (Het Group name = COH) matches with 51.11% similarity)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

Added reference

DOI no: 10.1074/jbc.M114.634014

J Biol Chem 290:7897-7909 (2015)

PubMed id: 25648895

13-Methylarachidonic acid is a positive allosteric modulator of endocannabinoid oxygenation by cyclooxygenase.

S.N.Kudalkar, S.P.Nikas, P.J.Kingsley, S.Xu, J.J.Galligan, C.A.Rouzer, S.Banerjee, L.Ji, M.R.Eno, A.Makriyannis, L.J.Marnett.

ABSTRACT

Cyclooxygenase-2 (COX-2) oxygenates arachidonic acid (AA) and the endocannabinoids 2-arachidonoylglycerol (2-AG) and arachidonylethanolamide to prostaglandins, prostaglandin glyceryl esters, and prostaglandin ethanolamides, respectively. A structural homodimer, COX-2 acts as a conformational heterodimer with a catalytic and an allosteric monomer. Prior studies have demonstrated substrate-selective negative allosteric regulation of 2-AG oxygenation. Here we describe AM-8138 (13(S)-methylarachidonic acid), a substrate-selective allosteric potentiator that augments 2-AG oxygenation by up to 3.5-fold with no effect on AA oxygenation. In the crystal structure of an AM-8138·COX-2 complex, AM-8138 adopts a conformation similar to the unproductive conformation of AA in the substrate binding site. Kinetic analysis suggests that binding of AM-8138 to the allosteric monomer of COX-2 increases 2-AG oxygenation by increasing kcat and preventing inhibitory binding of 2-AG. AM-8138 restored the activity of COX-2 mutants that exhibited very poor 2-AG oxygenating activity and increased the activity of COX-1 toward 2-AG. Competition of AM-8138 for the allosteric site prevented the inhibition of COX-2-dependent 2-AG oxygenation by substrate-selective inhibitors and blocked the inhibition of AA or 2-AG oxygenation by nonselective time-dependent inhibitors. AM-8138 selectively enhanced 2-AG oxygenation in intact RAW264.7 macrophage-like cells. Thus, AM-8138 is an important new tool compound for the exploration of allosteric modulation of COX enzymes and their role in endocannabinoid metabolism.