The effect of ammonium ions on the activity of glutamate dehydrogenase, alanine aminotransferase and aspartate aminotransferase in Cucumis sativus L. seedlings

Changes in the activity of glutamate dehydrogenase (GDH), alanine aminotransferase (GPT) and aspartate aminotransferase (GOT) were studied in various organs of Cucumis sativus L. seedlings in relation to the uptake of mineral nitrogen (in form of N03- or NH4+ ) from the medium. Activity of GDH, GPT, and GOT was higher in young leaves and roots of cucumber seedlings if the plants developed- in an ammonium medium. No similar changes of aminotransferases activity were noted in the cotyledons. Factors affecting varying effect of ammonium ions upon GPT and GOT activity are discussed for particular organs of cucumber seedlings