title: Direct production of ivermectin-like drugs after domain exchange in the avermectin polyketide synthase of Streptomyces avermitilis ATCC31272.
abstract: Ivermectin, a mixture of 22,23-dihydroavermectin B1a9 with minor amounts of 22,23-dihydroavermectin B1b 10, is one of the most successful veterinary antiparasitic drugs ever produced. In humans, ivermectin has been used for the treatment of African river blindness (onchocerciasis) resulting in an encouraging decrease in the prevalence of skin and eye diseases linked to this infection. The components of ivermectin are currently synthesized by chemical hydrogenation of a specific double bond at C22-C23 in the polyketide macrolides avermectins B1a 5 and B1b 6, broad-spectrum antiparasitic agents isolated from the soil bacterium Streptomyces avermitilis. We describe here the production of such compounds (22,23-dihydroavermectins B1a 9 and A1a 11) by direct fermentation of a recombinant strain of S. avermitilis containing an appropriately-engineered polyketide synthase (PKS). This suggests the feasibility of a direct biological route to this valuable drug.
authors.affiliation: Biotica Technology Limited, 181A Huntingdon Road, Cambridge, UK CB3 0DJ.
authors.forename: Sabine
authors.initials: S
authors.lastname: Gaisser
authors.forename: Laurenz
authors.initials: L
authors.lastname: Kellenberger
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Kaja
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Weston
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Lill
authors.forename: Gabriele
authors.initials: G
authors.lastname: Wirtz
authors.forename: Steven G
authors.initials: SG
authors.lastname: Kendrew
authors.forename: Lindsey
authors.initials: L
authors.lastname: Low
authors.forename: Rose M
authors.initials: RM
authors.lastname: Sheridan
authors.forename: Barrie
authors.initials: B
authors.lastname: Wilkinson
authors.forename: Ian S
authors.initials: IS
authors.lastname: Galloway
authors.forename: Kim
authors.initials: K
authors.lastname: Stutzman-Engwall
authors.forename: Hamish A
authors.initials: HA
authors.lastname: McArthur
authors.forename: James
authors.initials: J
authors.lastname: Staunton
authors.forename: Peter F
authors.initials: PF
authors.lastname: Leadlay
mesh_terms: D015139:Blotting, Southern; D015195:Drug Design; D005285:Fermentation; D005798:Genes, Bacterial; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D017434:Protein Structure, Tertiary; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism*
chemical_list: D009097:Multienzyme Complexes; D007559:Ivermectin; C019264:avermectin