Molecular and General Genetics MGG

, Volume 235, Issue 2–3, pp 205–212 | Cite as

The developmentally regulated Aspergillus nidulans wA gene encodes a polypeptide homologous to polyketide and fatty acid synthases

  • María E. Mayorga
  • William E. Timberlake
Original Articles


The Aspergillus nidulans wA gene is required for synthesis of a green pigment present in the walls of mature asexual spores (conidia); wA mutants produce colorless (white) conidia. We determined the transcriptional structure and DNA sequence of the wA gene. wA consists of 5 exons separated by short (40–60 bp) introns. The processed transcript has the potential to encode a protein consisting of 1986 amino acid residues. The predicted WA polypeptide showed extensive sequence similarities with bacterial and fungal polyketide synthases and vertebrate fatty acid synthases, particularly within conserved active sites. Properties of the yellow conidial wall pigment intermediate suggest that it is a polyketide rather than a fatty acid. It is therefore likely that wA encodes all or part of a polyketide synthase involved in the formation of this pigment intermediate.

Key words

Aspergillus nidulans Polyketide synthase Filamentous fungus Spore Pigment 


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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • María E. Mayorga
    • 1
  • William E. Timberlake
    • 1
    • 2
  1. 1.Department of GeneticsUniversity of GeorgiaAthensUSA
  2. 2.Department of Plant PathologyUniversity of GeorgiaAthensUSA

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