The steroid hormones testosterone, androstenedione, progesterone and their
metabolic products testosterone acetate and testololactone were identified
as endogenously synthesised molecules in the fungus Pleurotus ostreatus. We
discuss the possible steroidogenic pathway in the fungus in view of the ev
olutionary origin of the steroid hormone signalling system. (C) 1999 Elsevi
er Science Inc. All rights reserved.