Relationships between nitrate uptake and nitrate reductase activity in Cucumis sativus L., roots

摘要

Anti-NR IgG fragments obtained after papain digestion of polyclonal antibodies gave the positive immunological reaction with both, a soluble and plasma membrane-bound nitrate reductase. Anti-NR antibody as well as IgG fragments almost totally inhibited the nitrate reductase activity in cytosol proving a crossreaction of antibody with the catalytic site of a soluble NR. Anti-NR EgG fragments, but not undigested polyclonal antibodies affected the activity of the nitrate reductase associated with Plasma membranes. Discrepancy in the action of intact antibodies and fragments obtained after they digestion were inter- Preted as a consequence of same differences in the action of those molecules to the penetration through the membrane.