L-tyrosine induces the production of a pyomelanin-like pigment by the parasitic yeast-form of Histoplasma capsulatum.
Medical mycology
confidence
Key findings
L-tyrosine induced pyomelanin-like pigment production in yeast form of H. capsulatum; mycelial cultures not melanized.
View source on PubMed (PMID 28992332) ↗
- Sample size
- 30 strains
- Population
- In vitro clinical and environmental Histoplasma capsulatum strains
- Dosing
- L-tyrosine in culture media
- Duration
- Not reported
- Route
- In vitro culture
- Blinding
- not_reported
- Controls
- none
- Drug class
- amino acid
Full abstract
Melanization of Histoplasma capsulatum remains poorly described, particularly in regards to the forms of melanin produced. In the present study, 30 clinical and environmental H. capsulatum strains were grown in culture media with or without L-tyrosine under conditions that produced either mycelial or yeast forms. Mycelial cultures were not melanized under the studied conditions. However, all strains cultivated under yeast conditions produced a brownish to black soluble pigment compatible with pyomelanin when grew in presence of L-tyrosine. Sulcotrione inhibited pigment production in yeast cultures, strengthening the hyphothesis that H. capsulatum yeast forms produce pyomelanin. Since pyomelanin is produced by the fungal parasitic form, this pigment may be involved in H. capsulatum virulence.