Abstract:A antimicrobial protein was isolated and purified from Chlorella pacifica using ammonium sulfate precipitation, ion exchange chromatography on DEAE-52, and then gelfiltration on SephadexG-200. By SDS-PAGE determination, the protein appears two bands with molecular weight of 61 kD and 70 kD, respectively. The protein consists of seventeen amino acids, in which the contents of Glu, Gly and Asp are abundant. The protein had strong antifungal activity against Penicillium chrysogenum and Rhizopus chinensis, and also exhibited antibacterial activity against Staphylococcus aureus and Ameromonas punctata. The protein was stable under heat stress. Antifungal activities were stronger than antibacterial activitives in the antimicrobial protein from Chlorella pacifica.