Bioassay-Guided Evolution of Glycosylated Macrolide Antibiotics in Escherichia coli.

Ho Young Lee; Khosla, Chaitan

Macrolide antibiotics such as erythromycin are clinically important polyketide natural products. We have engineered a recombinant strain of Escherichia coli that produces small but measurable quantities of the bioactive macrolide 6-deoxyerythromycin D. Bioassay-guided evolution of this strain led to the identification of an antibiotic-overproducing mutation in the mycarose biosynthesis and transfer pathway that was detectable via a colony-based screening assay. This high-throughput assay was then used to evolve second-generation mutants capable of enhanced precursordirected biosynthesis of macrolide antibiotics. The availability of a screen for macrolide biosynthesis in E. coli offers a fundamentally new approach in dissecting modular megasynthase mechanisms as well as engineering antibiotics with novel pharmacological properties.

BIOLOGICAL assay; ERYTHROMYCIN; MACROLIDE antibiotics; ESCHERICHIA coli; GENETIC mutation; BIOCHEMICAL engineering

PLoS Biology, 2007, Vol 5, Issue 2, p243

1544-9173

Academic Journal

10.1371/journal.pbio.0050045