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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Trinuclear Metal Clusters in Catalysis by Terpenoid Synthases
Julie A Aaron1, David W Christianson
1Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104-6323, USA.
Pure and Applied Chemistry. Chimie Pure Et Appliquee
|September 28, 2011
Summary
Class I terpenoid synthases are crucial enzymes for creating diverse natural products. A conserved trinuclear metal cluster and hydrogen bond donors are key to their catalytic mechanism across many species.
Area of Science:
- Biochemistry
- Enzymology
- Natural Product Synthesis
Background:
- Terpenoid synthases are vital enzymes producing diverse isoprenoid natural products.
- Class I terpenoid synthases, found across bacteria, fungi, protists, plants, and animals, share a common structural fold.
- Despite low sequence identity, these enzymes possess conserved metal-binding motifs.
Purpose of the Study:
- To elucidate the conserved structural and functional elements of class I terpenoid synthases.
- To understand the role of the metal cluster in substrate binding and catalysis.
- To investigate the universality of the catalytic mechanism across different organisms.
Main Methods:
- Comparative analysis of amino acid sequences to identify conserved motifs.
- Structural analysis using X-ray crystallography.
- Biochemical assays to study enzyme kinetics and mechanism.
Main Results:
- Class I terpenoid synthases utilize a conserved trinuclear metal cluster for substrate binding and diphosphate release.
- Conserved hydrogen bond donors assist the metal cluster in initiating carbocation formation.
- The constellation of three metal ions is generally identical across known class I terpenoid synthases.
Conclusions:
- The trinuclear metal cluster and associated hydrogen bond donors represent a conserved catalytic machinery for class I terpenoid synthases.
- This conserved mechanism facilitates the generation of diverse isoprenoid natural products.
- Structural and mechanistic insights provide a foundation for understanding terpenoid biosynthesis.
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