Has bacteriostatic activity against the Gram-positive bacterium M.luteus, but not against Gram-negative bacterium E.coli SBS363. Has fungistatic activity against C.neoformans, but not C.albicans. Binds and sequesters copper and iron ions. Copper-chelating is crucial for antimicrobial activity against M.luteus. Expressed in the hemocytes, fat body and ovaries.