Alocasin, an anti-fungal protein from rhizomes of the giant taro Alocasia macrorrhiza.

An anti-fungal protein designated alocasin was isolated from the rhizomes of the giant taro Alocasia macrorrhiza. The isolation protocol involved ion exchange chromatography on diethylaminoethyl (DEAE)-cellulose, ion exchange chromatography on sulfopropyl (SP)-Sepharose, and gel filtration on Superdex 75. Alocasin, which was unadsorbed on DEAE-cellulose and SP-Sepharose, possessed the N-terminal sequence APEGEV, which exhibited some similarity to that of the miraculin-like anti-fungal protein from Pisum sativum legumes. It demonstrated a molecular mass of 11kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, and displayed anti-fungal activity against Botrytis cinerea. Alocasin reduced the activity of HIV-1 reverse transcriptase. It exhibited weak hemagglutinating activity, only at a concentration of 1mg/ml.