Axel A. Brakhage

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Expression of the Aspergillus nidulans penicillin biosynthesis genes acvA and ipnA, encoding delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase and isopenicillin N synthetase, respectively, was analyzed. The intergenic region carrying the divergently oriented promoters was fused in frame in both orientations to Escherichia coli lacZ and E. coli(More)
A homologous transformation system for the opportunistic fungal pathogen Aspergillus fumigatus was developed. It is based on the A. fumigatus pyrG gene, encoding orotidine 5′-monophosphate decarboxylase, which was cloned and sequenced. Transformation of both Aspergillus (Emericella) nidulans and A. fumigatus pyrG mutant strains by the use of protoplasts or(More)
Aspergillus fumigatus is an important pathogen of immunocompromised hosts, causing pneumonia and invasive disseminated disease with high mortality. The factors contributing to the predominance of A. fumigatus as an opportunistic pathogen are largely unknown. Since the survival of conidia in the host is a prerequisite for establishing disease, we have been(More)
In the postgenomic era it has become increasingly apparent that the vast number of predicted biosynthesis genes of microorganisms is not reflected by the metabolic profile observed under standard fermentation conditions. In the absence of a particular (in most cases unknown) trigger these gene loci remain silent. Because these cryptic gene clusters may code(More)
Aspergillus fumigatus, the most common airborne fungal pathogen of humans, employs two high-affinity iron uptake systems: iron uptake mediated by the extracellular siderophore triacetylfusarinine C and reductive iron assimilation. Furthermore, A. fumigatus utilizes two intracellular siderophores, ferricrocin and hydroxyferricrocin, to store iron.(More)
For more than 40 years fungi have been known to produce pigments known as melanins. Predominantly these have been dihydroxyphenylalanine (DOPA)-melanin and dihydroxynaphthalene (DHN)-melanin. The biochemical and genetical analysis of the biosynthesis pathways have led to the identification of the genes and corresponding enzymes of the pathways. Only(More)
Fungi produce a multitude of low-molecular-mass compounds known as secondary metabolites, which have roles in a range of cellular processes such as transcription, development and intercellular communication. In addition, many of these compounds now have important applications, for instance, as antibiotics or immunosuppressants. Genome mining efforts(More)
The air we breathe is filled with thousands of fungal spores (conidia) per cubic metre, which in certain composting environments can easily exceed 10(9) per cubic metre. They originate from more than a hundred fungal species belonging mainly to the genera Cladosporium, Penicillium, Alternaria and Aspergillus. Although these conidia contain many antigens and(More)
Mitogen-activated protein kinase (MAPK) cascades and the calcium-calcineurin pathway control fundamental aspects of fungal growth, development and reproduction. Core elements of these signalling pathways are required for virulence in a wide array of fungal pathogens of plants and mammals. In this review, we have used the available genome databases to(More)
Aspergillus fumigatus is the most important airborne fungal pathogen causing life-threatening infections in immunocompromised patients. Macrophages and neutrophils are known to kill conidia, whereas hyphae are killed mainly by neutrophils. Since hyphae are too large to be engulfed, neutrophils possess an array of extracellular killing mechanisms including(More)