Characterization of the ferrichrome A biosynthetic gene cluster in the homobasidiomycete Omphalotus olearius

Under iron deprivation Omphalotus olearius was found to produce the hydroxamate siderophore ferrichrome A. A gene cluster consisting of three genes: fso1, a nonribosomal peptide synthetase whose expression is enhanced in the absence of iron; omo1, a L-ornithine-N-5-monooxygenase, and ato1, an acyltransferase probably involved in the transfer of the methylglutaconyl residue to N-5-hydroxyorinithine was identified. The fso1 sequence is interrupted by 48 introns and its derived protein sequence has a similar structure to the homologous genes of Ustilago maydis and Aspergillus nidulans. This is the first report of a nonribosomal peptide synthetase gene and a biosynthetic gene cluster in homobasidiomycetes. (c) 2005 Federation of European Micro biological Societies. Published by Elsevier B.V. All rights reserved.