Recombinant AfusinC, an anionic fungal CSαβ defensin from Aspergillus fumigatus, exhibits antimicrobial activity against gram-positive bacteria

Antimicrobial peptides (AMPs) are short and generally positively charged peptides found in a wide variety of organisms. CSαβ defensins are a group of AMPs. These defensins are composed of an α-helix and a β-sheet linked by three or four disulphide bridges. In this study, we describe the antimicrobial activity of an anionic CSαβ fungal defensin from Aspergillus fumigatus , AfusinC. AfusinC was recombinantly produced as a fusion protein in Escherichia coli . The tag was removed by proteolytic cleavage, and AfusinC was purified by size exclusion chromatography. About 0.8 mg of recombinant AfusinC was obtained from 1 L of culture. Recombinant AfusinC was active against mainly gram-positive bacteria including human pathogens and a multiresistant-strain of A . aureus . Additionally, AfusinC showed bactericidal effect against Micrococcus luteus .