A polyketide synthase gene required for biosynthesis of fumonisin mycotoxins in Gibberella fujikuroi mating population A

Fungal Genet Biol. 1999 Jun;27(1):100-12. doi: 10.1006/fgbi.1999.1141.


Fumonisins are toxins associated with several mycotoxicoses and are produced by the maize pathogen Gibberella fujikuroi mating population A (MP-A). Biochemical analyses indicate that fumonisins are a product of either polyketide or fatty acid biosynthesis. To isolate a putative polyketide synthase (PKS) gene involved in fumonisin biosynthesis, we employed PCR with degenerate PKS primers and a cDNA template prepared from a fumonisin-producing culture of G. fujikuroi. Sequence analysis of the single PCR product and its flanking DNA revealed a gene (FUM5) with a 7.8-kb coding region. The predicted FUM5 translation product was highly similar to bacterial and fungal Type I PKSs. Transformation of a cosmid clone carrying FUM5 into G. fujikuroi enhanced production in three strains and restored wild-type production in a fumonisin nonproducing mutant. Disruption of FUM5 reduced fumonisin production by over 99% in G. fujikuroi MP-A. Together, these results indicate that FUM5 is a PKS gene required for fumonisin biosynthesis.

MeSH terms

  • 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase / genetics
  • Amino Acid Sequence
  • Carboxylic Acids / metabolism*
  • DNA Primers
  • DNA, Fungal / genetics
  • Fumonisins*
  • Genes, Fungal / genetics
  • Genetic Complementation Test
  • Genetic Vectors
  • Gibberella / enzymology
  • Gibberella / genetics*
  • Isoenzymes / genetics
  • Molecular Sequence Data
  • Multienzyme Complexes / genetics*
  • Multienzyme Complexes / metabolism
  • Mutagenesis, Site-Directed
  • Mutation
  • Mycotoxins / biosynthesis*
  • Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Transformation, Genetic


  • Carboxylic Acids
  • DNA Primers
  • DNA, Fungal
  • Fumonisins
  • Isoenzymes
  • Multienzyme Complexes
  • Mycotoxins
  • fumonisin B2
  • fumonisin B3
  • fumonisin B1
  • beta-ketoacyl-acyl carrier protein synthase I
  • 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase

Associated data

  • GENBANK/AF155773