INDUCTION AND LOCALIZATION OF A LIPOXYGENASE FROM FUSARIUM-PROLIFERATUM

Biomass of the fungus Fusarium proliferatum was produced in liquid med ium and used to obtain a crude enzymatic extract, Several methods were tested to obtain this extract: sonication, cryofracture and protoplas ts disintegration. A lipoxygenase activity was found in this crude ext ract, which was highly induced when the fungus was grown in a medium c ontaining soya oil rich in linoleic acid. Studies on the subcellular l ocalization were performed using differential centrifugation technique s which allowed separation of the main organites. Homogeneity of separ ated fractions was ensured by measuring specific enzymatic activities, succinate dehydrogenase for mitochondrial fractions and NADH-cytochro me C reductase for microsomal fraction. The results of subcellular fra ctionation suggest that lipoxygenase is mainly distributed among micro somal and mitochondrial fractions. (C) 1998 Elsevier Science B.V. All rights reserved.