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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products

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Published on: October 4, 2019

cis or trans with class II diterpene cyclases.

Meirong Jia¹, Reuben J Peters

¹Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50010, USA. rjpeters@iastate.edu.

Organic & Biomolecular Chemistry

|March 25, 2017

Summary

Isoprenoid cyclization can produce decalin bicycles regardless of alkene configuration. Class II diterpene cyclases accept both (E,E,E)- and (Z,Z,Z)-diphosphates, yielding distinct decalin products.

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Area of Science:

Organic Chemistry
Biochemistry
Enzymology

Background:

Isoprenoids are versatile natural products that undergo electrophilic cyclization.
The stereochemical outcome of isoprenoid cyclization is often dictated by substrate configuration.
Class II diterpene cyclases typically synthesize (E,E,E)-geranylgeranyl diphosphate derived products.

Purpose of the Study:

To investigate the substrate specificity of class II diterpene cyclases.
To determine if alkene configuration influences the cyclization of isoprenoid precursors.
To explore the synthesis of novel decalin bicycles.

Main Methods:

Enzymatic assays using class II diterpene cyclases.
Synthesis and characterization of (E,E,E)-geranylgeranyl diphosphate and (Z,Z,Z)-nerylneryl diphosphate.
Analysis of cyclization products using NMR spectroscopy.

Main Results:

Class II diterpene cyclases accepted both (E,E,E)-geranylgeranyl diphosphate and (Z,Z,Z)-nerylneryl diphosphate.
Cyclization of (E,E,E)-geranylgeranyl diphosphate yielded the expected 13E-trans-decalin bicycles.
Cyclization of (Z,Z,Z)-nerylneryl diphosphate produced novel 13Z-cis-decalin bicycles.

Conclusions:

The stereochemical configuration of the isoprenoid precursor does not prevent cyclization by class II diterpene cyclases.
Class II diterpene cyclases can produce distinct decalin bicycle stereoisomers based on substrate configuration.
This expands the scope of enzymatic isoprenoid cyclization for generating molecular diversity.