Generation of novel pikromycin antibiotic products through mutasynthesis.
The pikromycin polyketide synthase (PKS) of S. venezuelae, which consists of one loading module and six extension modules, is responsible for the formation of the hexaketide narbonolide, a key intermediate in the biosynthesis of the antibiotic pikromycin. S. venezuelae strains in which PikAI, which houses the loading domain and first two modules of the PKS, is either absent or catalytically inactive, produce no pikromycin product. When these strains are grown in the presence of a synthetically prepared triketide product, activated as the N-acetylcysteamine thioester, pikromycin yields are restored to as much as 11 % of that seen in the wild-type strain. Feeding analogues of the triketide intermediate provides pikromycin analogues bearing different alkyl substituents at C13 and C14. One of these analogues, Delta(15,16)-dehydropikromycin, exhibits improved antimicrobial activity relative to pikromycin.
Department of Chemistry, Portland State University, Portland, OR 97201, USA.
Shuchi
S
Gupta
Venkatraman
V
Lakshmanan
Beom Seok
BS
Kim
Robert
R
Fecik
Kevin A
KA
Reynolds
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry; D001419:Bacteria / Q000187:drug effects; D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D011487:Protein Conformation; D013302:Streptomyces / Q000254:growth & development / Q000378:metabolism; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D018942:Macrolides; C003145:picromycin