Developmental expression of β-glucosidase in olive leaves.

Plant β-glucosidases catalyze the hydrolysis of glycosidic linkages and play a vital role in defense against pathogens and stress. The present work investigated the relationship between leaf development and β-glucosidase protein content in Olea europea L. (cv. Picual) leaves. The total chlorophyll content increased with leaf age in current-season leaves. Immunoblot analysis revealed that the content of 61 kD protein of β-glucosidase also increased with leaf age, and that the enzyme existed in three isoforms (pI 5.8–6.2). Statistical analysis indicated a strong correlation between chlorophyll and β-glucosidase protein contents.