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Updated: May 21, 2026
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From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
Published on: January 13, 2017
Horizontal gene transfer and gene conversion drive evolution of modular polyketide synthases
Jurica Zucko1, Paul F Long, Daslav Hranueli
1Department of Genetics, University of Kaiserslautern, Postfach 3049, 67653, Kaiserslautern, Germany.
Journal of Industrial Microbiology & Biotechnology
|May 31, 2012
Summary
Soil bacteria produce novel compounds through evolution. Studying complete polyketide synthase gene clusters reveals horizontal gene transfer and gene conversion drive the evolution of these important pharmaceutical compounds.
Area of Science:
- Microbial genetics
- Evolutionary biology
- Biochemistry
Background:
- Soil bacteria compete in a rich environment, producing diverse secondary metabolites.
- These metabolites are crucial for pharmaceutical drug discovery, necessitating an understanding of their evolutionary origins.
- Modular polyketide synthases (PKS) offer a DNA-sequence-based approach to studying compound evolution.
Purpose of the Study:
- To investigate the evolutionary pathways of modular polyketide synthases by analyzing complete gene clusters.
- To identify and characterize orthologous modules and domains within these clusters.
- To develop a model for the evolution of PKS clusters, including horizontal gene transfer and gene conversion.
Main Methods:
- Analysis of 17 modular polyketide synthase clusters, categorized into six classes.
- Phylogenetic analysis to detect gene conversion by identifying discordant trees.
- Comparative genomics to identify instances of horizontal gene transfer between clusters.
Main Results:
- Gene conversion is prevalent in PKS clusters, affecting approximately 15% of domains.
- A novel evolutionary model is proposed involving horizontal gene transfer followed by gene conversion and deletions.
- Two potential examples of horizontal gene transfer events shaping PKS cluster architecture were identified.
Conclusions:
- Complete PKS cluster analysis provides a robust framework for studying evolutionary pathways.
- Horizontal gene transfer is a significant driver in the evolution of PKS gene clusters, leading to novel chemical structures.
- The proposed model offers strategies for identifying horizontal gene transfer in microbial secondary metabolite evolution.
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