[Mode of action of terrazoleon Mucor mucedo]

It is assumed that the fungistatic effect of terrazol in Mucor mucedo is induced by a liberation of phospholipases within within the mitochondria and perhaps at other membranes. In isolated mitochondria a rapid formation of lysolecithin can be demonstrated at low concentrations of terrazol. This would explain the lytic symptoms in mitochondria visible by electron microscopy. Lipid peroxidation could not be demonstrated. The only antidots at present known for the growth inhibiting effect of terrazol and on its ultrastructural effects are impure saccharose, which seems to contain an unknown factor, and procain hydrochloride or to a lesser extent lidocain, which are well-known inhibitors of phospholipases. The pathological thickening of the cell wall induced by terazol seems to be an unspecific side effect reflecting a diminished phosphorylating activity of the mitochondria.