DEVELOPMENT AND CHARACTERIZATION OF A MONOCLONAL-ANTIBODY TO PHYTOSIDEROPHORES

Mugineic acid-family phytosiderophores (MAs) are low molecular weight chelators that are secreted by graminaceous plants, form complexes wit h soil Fe(III) and are essential for plant growth. Methods to detect M AS which include HPLC and radio-immunoassay with polyclonal antibody r equire sophisticated equipment or radio-labelled MAs which are difficu lt to synthesize. Our objective was to develop a detection and quantit ation system for MAs based on monoclonal antibody specificity and tech nology. A monoclonal antibody was produced which reacts with nicotiana mine (NA), deoxymugineic acid (DMA), mugineic acid (MA) and epi-hydrox ymugineic acid (epi-HMA) in a competitive ELISA. Azetidine-2-carboxyli c acid (A-2-C) was not reactive while N-(3-amino-3-carboxypropyl) azet idine-2-carboxylic acid (A-2-C dimer) was partially reactive. The rang e of detection using the competitive ELISA is from 2 x 10(-6) to 2 x 1 0(-7) M MAs. Besides detection and quantification of MAs, the potentia l uses for the monoclonal antibody are numerous and include affinity c hromatography and immunocytochemistry.