ABSTRACT
Small, cysteine-rich and cationic antifungal proteins from natural sources are promising candidates for the development of novel treatment strategies to prevent and combat infections caused by drug-resistant fungi. However, limited information about their structure and antifungal mechanism hampers their future applications. In the present study, we determined the solution structure, dynamics and associated solvent areas of the Neosartorya (Aspergillus) fischeri antifungal protein NFAP. Genome mining within the genus revealed the presence of orthologous genes in N. fischeri and Neosartorya spathulata, and genes encoding closely related proteins can be found in Penicillium brasiliensis and Penicillium oxalicum. We show that the tertiary structure of these putative proteins can be resolved using the structure of NFAP as reliable template for in silico prediction. Localization studies with fluorescence-labelled protein pointed at an energy-dependent uptake mechanism of NFAP in the sensitive model fungus Neurospora crassa and subsequent cytoplasmic localization coincided with cell-death induction. The presented results contribute to a better understanding of the structure/function relationship of NFAP and related proteins and pave the way towards future antifungal drug development.
Subject(s)
Fungal Proteins/chemistry , Fungal Proteins/metabolism , Neosartorya/chemistry , Phylogeny , Amino Acid Sequence , Cytoplasm/metabolism , Models, Molecular , Neosartorya/cytology , Protein Conformation , Protein Transport , Sequence Homology, Amino Acid , SolutionsABSTRACT
We report here a case of allergic fungal rhinosinusitis caused by Neosartorya hiratsukae. This fungus was never previously been isolated from any case with fungal rhinosinusitis. The identification of this agent was confirmed by comparing the nucleotide sequence of the ITS region of ribosomal DNA with that in the GenBank DNA database. Identification of N. hiratsukae on the basis of colony morphology and microscopic feature may be difficult due to similarities with a few Aspergillus species. Scanning electron microscopy or DNA sequence analysis is essential for the accurate identification.
Subject(s)
Mycoses/diagnosis , Neosartorya/isolation & purification , Rhinitis, Allergic, Perennial/microbiology , Sinusitis/microbiology , Adult , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Humans , India , Male , Molecular Sequence Data , Mycoses/microbiology , Neosartorya/cytology , Neosartorya/genetics , Phylogeny , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNAABSTRACT
Cynodon dactylon (Bermuda grass) has been observed to grow sporadically on the surface of coal dumps in the Witbank coal mining area of South Africa. Root zone investigation indicated that a number of fungal species may be actively involved in the biodegradation of hard coal, thus enabling the survival of the plant, through mutualistic interaction, in this extreme environment. In an extensive screening program of over two thousand samples, the Deuteromycete, Neosartorya fischeri, was isolated and identified. The biodegradation of coal by N. fischeri was tested in flask studies and in a perfusion fixed-bed bioreactor used to simulate the coal dump environment. The performance of N. fischeri was compared to Phanaerochaete chrysosporium and Trametes (Polyporus) versicolor, previously described in coal biodegradation studies. Fourier transform infrared spectrometry and pyrolysis gas chromatography mass spectrometry of the biodegradation product indicated oxidation of the coal surface and nitration of the condensed aromatic structures of the coal macromolecule as possible reaction mechanisms in N. fischeri coal biodegradation. This is a first report of N. fischeri-mediated coal biodegradation and, in addition to possible applications in coal biotechnology, the findings may enable development of sustainable technologies in coal mine rehabilitation.
