Mutational analysis reveals that all tailoring region genes are required for production of polyketide antibiotic mupirocin by Pseudomonas fluorescens: pseudomonic acid B biosynthesis precedes pseudomonic acid A

Research output: Contribution to journalArticle


  • J Wu
  • Jennifer Shields
  • J Haddock
  • N Johnson
  • SM Cooper
  • Elton Stephens
  • RJ Cox
  • J Crosby
  • CL Willis
  • TJ Simpson

Colleges, School and Institutes


The Pseudomonas fluorescens mupirocin biosynthetic cluster encodes six proteins involved in polyketide biosynthesis and 26 single polypeptides proposed to perform largely tailoring functions. In-frame deletions in the tailoring open reading frames demonstrated that all are required for mupirocin production. A bidirectional promoter region was identified between mupF, which runs counter to other open reading frames and its immediate neighbor macpC, implying the 74-kb cluster consists of two transcriptional units. mupD/E and mupJ/K must be cotranscribed as pairs for normal function implying co-assembly during translation. MupJ and K belong to a widely distributed enzyme pair implicated, with MupH, in methyl addition. Deletion of mupF, a putative ketoreductase, produced a mupirocin analogue with a C-7 ketone. Deletion of mupC, a putative dienoyl CoA reductase, generated an analogue whose structure indicated that MupC is also implicated in control of the oxidation state around the tetrahydropyran ring of monic acid. Double mutants with DeltamupC and DeltamupO, DeltamupU, DeltamupV, or DeltamacpE produced pseudomonic acid B but not pseudomonic acid A, as do the mupO, U, V, and macpE mutants, indicating that MupC must work after MupO, U, and V.


Original languageEnglish
Pages (from-to)15451-15461
Number of pages11
JournalJournal of Biological Chemistry
Early online date23 Mar 2007
Publication statusPublished - 29 Mar 2007