Fungicidal properties of a chymotrypsin-like cationic protein from human neutrophils: adsorption to Candida parapsilosis

Abstract

Human neutrophils contain a chymotrypsin-like cationic protein (CLCP) that binds to the surface of Candida parapsilosis and is preferentially adsorbed by yeasts mixed with unfractionated extracts of neutrophil granules. Adsorption of CLCP to opsonized or nonopsonized yeasts was rapid at pH 4 through 8. Irreversible inhibition of the enzymatic site of CLCP by phenylmethylsulfonylfluoride or N-acetyl-Ala-Ala-Phe-chloromethyl ketone did not affect its adsorption by yeast. Adsorption, highly sensitive to ionic strength, was abrogated by 0.15 M KCl. The number of CLCP molecules adsorbed per yeast cell and the loss of colony-forming units are described by an exponential relationship.