7EQL

Crystal structure of (+)-pulegone reductase from Mentha piperita

Summary for 7EQL

• Entry DOI: 10.2210/pdb7eql/pdb
• Descriptor: (+)-pulegone reductase (1 entity in total)
• Functional Keywords: double bond reductase, plant protein
• Biological source: Mentha piperita (Peppermint, Mentha aquatica x Mentha spicata)
• Total number of polymer chains: 1
• Total formula weight: 37952.72

Authors

Lin, W. (deposition date: 2021-05-03, release date: 2021-09-29, Last modification date: 2023-11-29)

Primary citation

Liu, C.,Gao, Q.,Shang, Z.,Liu, J.,Zhou, S.,Dang, J.,Liu, L.,Lange, I.,Srividya, N.,Lange, B.M.,Wu, Q.,Lin, W.
Functional Characterization and Structural Insights Into Stereoselectivity of Pulegone Reductase in Menthol Biosynthesis.
Front Plant Sci, 12:780970-780970, 2021

PubMed Abstract: Monoterpenoids are the main components of plant essential oils and the active components of some traditional Chinese medicinal herbs like Briq Briq (L.) Britt (Blanco) Benth. Pulegone reductase is the key enzyme in the biosynthesis of menthol and is required for the stereoselective reduction of the Δ double bond of pulegone to produce the major intermediate menthone, thus determining the stereochemistry of menthol. However, the structural basis and mechanism underlying the stereoselectivity of pulegone reductase remain poorly understood. In this study, we characterized a novel (-)-pulegone reductase from (PR), which can catalyze (-)-pulegone to (+)-menthone and (-)-isomenthone through our RNA-seq, bioinformatic analysis in combination with enzyme activity assay, and determined the structure of (+)-pulegone reductase from (PR) by using X-ray crystallography, molecular modeling and docking, site-directed mutagenesis, molecular dynamics simulations, and biochemical analysis. We identified and validated the critical residues in the crystal structure of PR involved in the binding of the substrate pulegone. We also further identified that residues Leu56, Val282, and Val284 determine the stereoselectivity of the substrate pulegone, and mainly contributes to the product stereoselectivity. This work not only provides a starting point for the understanding of stereoselectivity of pulegone reductases, but also offers a basis for the engineering of menthone/menthol biosynthetic enzymes to achieve high-titer, industrial-scale production of enantiomerically pure products.

PubMed: 34917113
DOI: 10.3389/fpls.2021.780970

Experimental method

X-RAY DIFFRACTION (2.72 Å)