Tolypocladium inflation

A secondary metabolite produced by Tolypocladium inflation. This fungus was initially isolated in a soil sample collected in Norway. Cyclosporin A is a cyclic undecapeptide. Inside cells, cyclosporine A binds its immunophillin receptor known as cyclophillin. Like the FK506-FKBP12 complex, cyclosporin A-cyclophillin binds and inhibits the protein phosphatase calcineurin. 

Diagnosis Phialides produced singly, tolypocladium-like inflated, remaining inside the cuticle of the infected nematode, protruding only with the opening. Conidia globose, hyaline, smooth-walled, 1.8-2.5 p.m in diameter. 

Von Arx (1986) considered Tolypocladium a synonym of Beauveria on the basis of their resemblance in culture and the basally inflated conidiogenous cells. His conclusions have not been accepted by most authors, and molecular and biochemical characters do not support his arguments (Todorova et al., 1998 Mugnai et al., 1989 Kadlec et al., 1994). Harposporium is very similar, but has infrequently branched conidiophores, unusually shaped spores, forms a darker mycelium in axenic culture, and typically parasitizes nematodes and rotifers. 

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