12-oxophytodienoate reductase

Introduction

12-Oxophytodienoate reductase (OPR) is an enzyme that plays a key role in the biosynthesis of jasmonic acid (JA), a plant hormone involved in various physiological processes, including defense responses, growth regulation, and development. OPR catalyzes the reduction of 12-oxo-phytodienoic acid (OPDA) to produce the biologically active JA.

Function

12-oxophytodienoate reductase (OPR) catalyzes the conversion of (green) to 3-oxo-pentenyl-cyclopentane octanoate. The expression of OPR is induced by stimuli like touch, wind, wounding, UV light and detergent. OPR uses the cofactor (cyan) which is reduced by NADPH.

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• . Water molecules are shown as red spheres.
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OPR exhibits self inhibition by dimerization.^[1] Three isozymes of OPR are known – OPR1, OPR2, OPR3.

• OPR1 cleaves olefinic bonds in α,β-unsaturated carbonyls.
  
• OPR3 cleaves olefinic bonds in cyclic enones.

Relevance

OPR is part of the jasmonic acid synthesis pathway. Jasmonic acid is regulating plant responses to abiotic and biotic stresses.

3D Structures of 12-oxophytodienoate reductase

12-oxophytodienoate reductase 3D structures