Intracellular keratinase of Trichophyton gallinae

Trichophyton gallinae could grow on agar medium containing chicken feathers as sole sources of carbon and nitrogen, but it could not utilize human or guinea pig hair. The fungus grows rapidly when feather keratin solubilized in dimethyl sulphoxide was included in the growth medium. Keratinase activity could be detected by release of amino acids from solubilized keratin and by creation of zones of lysis in gel diffusion assay. However, the activity was observed only in homogenates of T. gallinae mycelia: it was not possible to detect it in culture filtrates.