Purification and Properties of Lectins from a Mushroom, Pleurotus cornucopiae

Abstract

Hemagglutinating activity in fruit bodies of Pleurotus cornucopiae was separated by DEAE column chromatography into two, adsorbed and unadsorbed, fractions. From the unadsorbed fraction, three active substances were purified and characterized. The main component (PCL-a) consisted of two identical subunits with an apparent molecular mass of 16kDa and the second (PCL-b) consisted of two heterogeneous subunits of 16 and 15kDa. The three lectins as well as the two kinds of subunits were immunologically cross-reactive with anti-PCL-a serum. Amino acid compositions of the two subunits were similar, and N-terminal residues of the subunits were blocked. Hemagglutinating activities of the three lectins were not inhibited by any monosaccharide tested but were strongly inhibited by asialo-mucin. From these results, the three lectins in P. cornucopiae were found to be isolectins.