Nitrogen Metabolite Repression of Metabolism and Virulence in the Human Fungal Pathogen Cryptococcus neoformans

  title={Nitrogen Metabolite Repression of Metabolism and Virulence in the Human Fungal Pathogen Cryptococcus neoformans},
  author={I. Russel Lee and Eve W L Chow and Carl A. Morrow and Julianne Teresa Djordjevic and James Angus Fraser},
  pages={309 - 323}
Proper regulation of metabolism is essential to maximizing fitness of organisms in their chosen environmental niche. Nitrogen metabolite repression is an example of a regulatory mechanism in fungi that enables preferential utilization of easily assimilated nitrogen sources, such as ammonium, to conserve resources. Here we provide genetic, transcriptional, and phenotypic evidence of nitrogen metabolite repression in the human pathogen Cryptococcus neoformans. In addition to loss of… 

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In the fungi, nitrogen metabolism is controlled by a complex genetic regulatory circuit which ensures the preferential use of primary nitrogen sources and also confers the ability to use many
Nitrogen metabolism and virulence of Candida albicans require the GATA‐type transcriptional activator encoded by GAT1
An important role for nitrogen regulation in the virulence of C. albicans is indicated and regulatory defect did not prevent filamentation of gat1Δ mutants in nitrogen repressing or non‐repressing conditions, demonstrating that nitrogen catabolite repression does not influence dimorphism.
The GATA-type transcriptional activator Gat1 regulates nitrogen uptake and metabolism in the human pathogen Cryptococcus neoformans.
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It is demonstrated that no individual nitrogen source was essential, while glucose was the most significant primary carbon source for yeast survival in vivo, and there was little or no requirement in vivo in this assay for any of the nitrogen-sensing pathways, nitrogen catabolite repression, the ammonium- or amino acid-s sensing pathways, or general control.
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The ability to produce melanin is a key virulence factor in many fungal pathogens including the human basidiomycete pathogen Cryptococcus neoformans, a major cause of life‐threatening infections
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