Involved in biosynthesis of mugineic acid family phytosiderophores, which are ferric iron chelators produced in graminaceous plants in response to iron deficiency. 2-oxoglutarate + nicotianamine = 3''-deamino-3''-oxonicotianamine + L-glutamate Expressed in companion and pericycle cells adjacent to the protoxylem of roots (PubMed:18034312). Expressed in companion cells of shoots (PubMed:18034312). Expressed in the scutellum and leaf primordium of fully mature seeds (PubMed:17333504). In germinating seeds, expressed in the vascular bundle of the scutellum, the coleoptile, the bud scale, the coleorhiza, and the base of the seminal root (PubMed:17333504). Induced by iron deficiency in roots and leaves. Belongs to the class-I pyridoxal-phosphate-dependent aminotransferase family. Truncated N-terminus. Truncated N-terminus.