About Wallemia ichthyophaga EXF-994 (GCA_000400465)
Wallemia ichthyophaga is one of the three species of fungi in the genus Wallemia, which in turn is the only genus of the class Wallemiomycetes.
W. ichthyophaga requires at least 1.5 M NaCl for in-vitro growth (or some other osmolyte for an equivalent water activity), and it thrives even in saturated NaCl solution. This makes it the most halophilic fungus known and distinguishes it from halotolerant (e.g. Aureobasidium pullulans) and extremely halotolerant fungi (e.g. Hortaea werneckii), which are able to grow well even in the absence of salt in the medium. These increase in size almost four-fold when exposed to high salinity, and the cell wall experiences a three-fold thickening.. This results in a substantially decreased functional cell volume and is thought to be one of the halotolerance mechanisms of this species. Contrary to what was observed for the extremely halotolerant H. werneckii, in W. ichthyophaga there are almost no expansions in metal cation transporter genes and their expression is not salt-responsive. On the other hand, there is a vast enrichment of hydrophobins (proteins of cell wall with diverse functions and many biotechnological uses), which contain an unusually high proportion of acidic amino acids. High proportion of acidic amino acids is thought to be an adaptation of proteins to high concentrations of salt.
Taxonomy ID 1299270
Data source European Nucleotide Archive
This species currently has no variation database. However you can process your own variants using the Variant Effect Predictor: