Purification, characterization, and cDNA cloning of an antifungal protein from the hemolymph of Sarcophaga peregrina (flesh fly) larvae.

An antifungal protein (AFP) was purified from the hemolymph of third instar larvae of Sarcophaga peregrina. This protein repressed the growth of Candida albicans in Sabouraud medium in the presence of nitrofurazone. However, in distilled water or saline, AFP alone killed C. albicans. Significant synergism was detected between AFP and sarcotoxin IA, an antibacterial protein of Sarcophaga. The lethal effect of AFP on C. albicans was greatly enhanced by the presence of a small amount of sarcotoxin IA. AFP was shown to bind to C. albicans and cause leakage of a substance(s) with absorbance at 260 nm from the cells. Analysis of its cDNA showed that AFP is a novel histidine-rich protein consisting of 67 amino acid residues.