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Updated: Jun 30, 2026
09:08
From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
Published on: January 13, 2017
Isoprenoid-like alkylations in polyketide biosynthesis
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA. ccalder2@macalester.edu
Natural Product Reports
|September 30, 2008
Summary
A newly discovered polyketide alkylation pathway creates complex beta-branched structures. This pathway parallels isoprenoid biosynthesis, expanding the diversity of accessible polyketide natural products.
Area of Science:
- Biochemistry
- Natural Product Biosynthesis
- Metabolic Engineering
Background:
- Polyketides are structurally diverse secondary metabolites produced by iterative Claisen condensation.
- Current polyketide biosynthesis knowledge primarily focuses on linear chain assembly.
- Access to branched polyketide structures remains limited.
Purpose of the Study:
- To describe a newly characterized polyketide alkylation pathway.
- To highlight parallels between this pathway and isoprenoid biosynthesis.
- To explore the structural diversity accessible through this novel route.
Main Methods:
- Review of recent literature on polyketide biosynthesis.
- Comparative analysis of enzymatic mechanisms in polyketide and isoprenoid pathways.
- Bioinformatic analysis of gene clusters associated with beta-branched polyketides.
Main Results:
- Characterization of a novel enzymatic sequence enabling beta-alkylation in polyketide chains.
- Identification of mechanistic similarities to prenyltransferases in isoprenoid metabolism.
- Demonstration of the pathway's capacity to generate a range of beta-branched polyketide scaffolds.
Conclusions:
- The newly identified alkylation pathway significantly expands the structural repertoire of polyketides.
- This pathway offers new opportunities for engineering novel polyketide natural products.
- Understanding this pathway provides insights into the evolution of metabolic pathways.
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