Chloroperoxidases from Caldariomyces (= Leptoxyphium) cultures: Glycoproteins with variable carbohydrate content and isoenzymic forms

Abstract

Twenty-six fungal cultures, including 10 Caldariomyces (= Leptoxyphium) cultures and 5 other capnodiaceous fungi, were examined for extracellular chloroperoxidase production on 4 growth media. Only the Caldariomyces cultures produced enzyme activity and enzyme production was highest on growth in a phytone medium. Chloroperoxidase was partly purified from the 10 Caldariomyces cultures. All preparations were glycoproteins, with different carbohydrate content. The absorption spectra of the 10 samples were indistinguishable and this was reflected in similar Rz (A403/A280) values. SDS-PAGE revealed two major bands of protein in all preparations but in different proportions: staining for carbohydrate confirmed these bands to be glycoproteins. PAGE at pH 3 showed each preparation to be composed of several isoenzymes and these could be grouped according to their migration patterns. Kinetic constants, where determined, and pH optima showed no differences among the 10 preparations and all exhibited catalase and peroxidase activities in the same relative proportions to chlorinating activity.