Differential induction of pectolytic enzymes of <i>Fusarium roseum</i> (Lk.) emend. Snyder and Hansen

Abstract

Pectolytic enzymes of Fusarium roseum were differentially induced at pH 3.5 and 6.5 in solutions of specific pectic substances. Endopolygalacturonase was induced in 0.02 M mucic acid and 1% polygalacturonic acid solutions at pH 6.5 and also in a 1% pectin solution at pH 3.5. Endopolymethylgalacturonase was induced in a 1% pectin solution at pH 6.5. In addition, pectinesterase and endopectin methyl-trans-eliminase were induced in 1% pectin solutions at pH 3.5 and 6.5, respectively.Inclusion of 0.005 M CaCl 2 in reaction mixtures inhibited the degradation of polygalacturonic acid by mucic and polygalacturonic acid induced polygalacturonase. In contrast, the breakdown of pectin by the pectinesterase and polygalacturonase induced in 1% pectin solutions, pH 3.5, was stimulated.