
Keywords: Zea mays L.; Cytokinin; Cytokinin dehydrogenase; Escherichia coli IMPACT expression system; Substrate preferenceAtCKX, cytokinin dehydrogenase from Arabidopsis thaliana; CKX, cytokinin dehydrogenase; cZ, cis-zeatin; cZ9G, cis-zeatin-N9-glucoside; cZRMP, c