Table I. Relative activity of recombinant and purified maize AAMT enzymes and OMT8 with various substrates

Values are averages of four independent measurements. All substrates were tested at a 1.5 mm concentration, and methyltransferase activity was determined by measuring the radioactivity of the transferred 14C-methyl group from SAM. The relative activity of the three AAMTs with anthranilic acid was set arbitrarily at 100%. nd, Not determined.

SubstrateAAMT1 Relative ActivityAAMT2 Relative ActivityAAMT3 Relative ActivityOMT8 Relative Activity
Anthranilic acid1001001000
Benzoic acid3326100
Salicylic acid0020
Indole-3-acetic acid002nd
Jasmonic acid001nd
Cinnamic acid0000
Coumaric acid0000