STIMULATION OF SCHIZOPHYLLUM-COMMUNE FRUIT BODY FORMATION BY INHIBITOR OF MEMBRANE-FUNCTION AND CELL-WALL SYNTHESIS

The fruit body formation of Schizophyllum commune was greatly stimulat ed by the addition of papulacandin B, aculeacin A, gramicidin S, lutei nizing hormone-releasing hormone (LH-RH), or digitonin to the culture media. Papulacandin B and aculeacin A inhibit glucan synthase, which w as demonstrated with S. commune in vitro in this study. The in vitro S . commune glucan synthase was activated by phospholipids that countera cted the stimulation of fruit body formation by papulacandin B. LH-RH, however, did not inhibit the glucan synthase. Digitonin was known to inhibit chitin synthase, but polyoxin B, a substrate analogue inhibito r of chitin synthase, did not stimulate the fruit body formation. The characteristic common to most of these stimulators of fruit body forma tion is possible induction of structural changes of plasma membranes t o which the substances can attach with their biphasic nature. These st imulators of fruit body formation were mostly accompanied by an eviden t suppression of hyphal growth, independent of phenoloxidase activity, and not observed in continuous dark or with monokaryotic strains.