Schizolysin, a hemolysin from the split gill mushroom Schizophyllum commune

Abstract

Abstract A monomeric hemolysin with a molecular mass of 29 kDa was isolated from fresh fruiting bodies of the split gill mushroom Schizophyllum commune. The hemolysin was purified by successive adsorption on DEAE-cellulose, carboxymethyl-cellulose and Q-Sepharose and finally gel filtration on Superdex 75. This demonstrated the N-terminal sequence ATNYNKCPGA, different from those of previously reported fungal and bacterial hemolysins. The hemolysin was stable up to 40 degrees C. Only partial activity remained at 50 and 60 degrees C. Activity was indiscernible at 70 degrees C. A pH of 6.0 was optimal for activity. The hemolytic activity was most potently inhibited by dithiothreitol, sucrose and raffinose, followed by cellobiose, maltose, rhamnose, inulin, lactose, fructose and inositol. The metal ions Cu(2+), Mg(2+), Zn(2+), Al(3+) and Fe(3+) significantly, and Pb(2+) to a lesser extent, curtailed the activity of the hemolysin. The hemolysin inhibited HIV-1 reverse transcriptase with an IC(50) of 1.8 microM.