SCHIZOSTATIN, A NOVEL SQUALENE SYNTHASE INHIBITOR PRODUCED BY THE MUSHROOM, SCHIZOPHYLLUM-COMMUNE .1. TAXONOMY, FERMENTATION, ISOLATION, PHYSICOCHEMICAL PROPERTIES AND BIOLOGICAL-ACTIVITIES

In the process of screening for squalene synthase inhibitors from micr obial fermentation products we have isolated a novel compound, named s chizostatin (Fig. 1), from the culture broth of the mushroom, Schizoph yllum commune SANK 17785. Schizostatin inhibited rat liver microsomal squalene synthase dose dependently and the IC50 value was 0.84 mu M. T he inhibition was competitive with respect to farnesylpyrophosphate wi th a Ki value of 0.45 mu M.