Production of capsule and conidia by yeast-like cells of<i>Phialophora spinifera</i>and<i>Phialophora jeanselmei</i>

Abstract

Five strains of Phialophora spinifera Nielsen & Conant 1968 isolated from natural sources as well as the original culture of Nielsen & Conant, produced on Czapek-Dox's sodium nitrate sucrose agar, single and multiple budding yeast-like cells mostly with a typical capsule. The yeast-like capsulated and non-capsulated cells produced on Czapek-Dox's agar, before 48 h at 28°C, usually from a small protuberance, successive non-capsulated elements showing the shape and size of the conidia of the species. Similar features were observed in the human strain of P. jeanselmei isolated by Murray, Dunkerley & Hughes. This strain converted later into a filamentous variant unable to produce yeast-like capsultaed cells. Two old strains of P. jeanselmei, Langeron's and Emmons's strains, showed only this filamentous form of growth.