The expression of selected non-ribosomal peptide synthetases in Aspergillus fumigatus is controlled by the availability of free iron

• Published in: FEMS microbiology letters Vol. 248; no. 1; pp. 83 - 91
• Main Authors: Reiber, Kathrin, Reeves, Emer P., Neville, Claire M., Winkler, Robert, Gebhardt, Peter, Kavanagh, Kevin, Doyle, Sean
• Format: Journal Article
• Language: English
• Published: Oxford, UK Elsevier B.V 01.07.2005; Blackwell Publishing Ltd; Blackwell
• Subjects: 4′-PPTase; Aspergillus fumigatus - enzymology; Aspergillus fumigatus - genetics; Aspergillus fumigatus - physiology; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Growth, nutrition, metabolism, transports, enzymes. Molecular biology; Iron; Iron - chemistry; Iron - metabolism; MALDI ToF; Microbiology; Mycology; NRPS; Peptide Synthases - genetics; Peptide Synthases - metabolism; Proteomics; Reverse Transcriptase Polymerase Chain Reaction; Secondary metabolites; Siderophore; Siderophores - metabolism; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; MALDI ToF; Secondary metabolites; NRPS; Siderophore; 4′-PPTase; Proteomics; Iron; Enzyme; 4'-PPTase; Fungi; Ligases; Fungi Imperfecti; Aspergillus fumigatus; Secondary metabolism; Reverse transcription polymerase chain reaction; Mass spectrometry; Thallophyta
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/j.femsle.2005.05.028

Three non-ribosomal peptide synthetase genes, termed sidD, sidC and sidE, have been identified in Aspergillus fumigatus. Gene expression analysis by RT-PCR confirms that expression of both sidD and C was reduced by up to 90% under iron-replete conditions indicative of a likely role in siderophore biosynthesis. SidE expression was less sensitive to iron levels. In addition, two proteins purified from mycelia grown under iron-limiting conditions corresponded to SidD (∼200 kDa) and SidC (496 kDa) as determined by MALDI ToF peptide mass fingerprinting and MALDI LIFT-ToF/ToF. Siderophore synthetases are unique in bacteria and fungi and represent an attractive target for antimicrobial chemotherapy.