L-tryptophan + O2 = CO2 + H2O + indole-3-acetamide Binds 1 FMN per subunit. Plant hormone metabolism; auxin biosynthesis. Belongs to the tryptophan 2-monooxygenase family. The plasmid pTiTM4 carries two T-regions, the TA and TB region, both of which have a functional iaaM gene, with low homology between them.