Related Experiment Video
Updated: Aug 13, 2026

From a Natural Product to Its Biosynthetic Gene Cluster: A Demonstration Using Polyketomycin from Streptomyces diastatochromogenes Tü6028
Published on: January 13, 2017
Broad substrate specificity of ketoreductases derived from modular polyketide synthases
Shilpa Bali1, Helen M O'Hare, Kira J Weissman
1Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
Recombinant ketoreductase (KR) enzymes from polyketide synthases (PKSs) show promise for creating chiral alcohols. Mutagenesis improved their ability to reduce non-polyketide substrates, enabling new biotransformation applications.
Area of Science:
- Biocatalysis and Enzyme Engineering
- Organic Chemistry
- Synthetic Biology
Background:
- Modular polyketide synthases (PKSs) are complex natural product assembly lines.
- Ketoreductase (KR) domains within PKSs catalyze stereoselective ketone reductions.
- Exploring KR domains for non-natural substrates offers new biocatalytic possibilities.
Purpose of the Study:
- To investigate the potential of recombinant ketoreductase (KR) domains from PKSs as catalysts for reducing non-polyketide substrates.
- To identify and engineer KR variants with enhanced activity and altered substrate specificity.
- To assess the feasibility of using PKS KRs for the enantioselective production of chiral alcohols.
Main Methods:
- Expression and purification of recombinant KR domains from antibiotic-producing PKSs.
- Enzyme activity assays using various non-polyketide substrates, including those with cyclohexyl moieties.
- Site-directed mutagenesis targeting key amino acid residues within the KR active site.
- Analysis of mutant enzyme activity and stereoselectivity.
Main Results:
- Recombinant KR domains exhibited significant catalytic activity toward non-polyketide substrates.
- Substrates incorporating cyclohexyl groups were particularly well-reduced.
- Site-directed mutagenesis yielded improved KR mutants with enhanced activity against target compounds.
- Engineered KRs demonstrated potential for specific chiral alcohol production.
Conclusions:
- PKS-derived KR domains are versatile biocatalysts for enantioselective reductions.
- Enzyme engineering can optimize KR activity for non-natural, industrially relevant substrates.
- These findings open avenues for PKS KRs in chiral alcohol synthesis and biotransformations.
More Related Videos
10:41The Logic, Experimental Steps, and Potential of Heterologous Natural Product Biosynthesis Featuring the Complex Antibiotic Erythromycin A Produced Through E. coli
Published on: January 13, 2013
07:59A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Related Concept Videos
Protecting Groups for Aldehydes and Ketones: Introduction
Reactions of Aldehydes and Ketones: Baeyer–Villiger Oxidation
The carbonyl center is activated by...
Other Glycolytic Pathways
Phase I Reactions: Reductive Reactions
α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes