Metabolism of Indole-3-Acetic Acid

Abstract
The metabolism of labeled IAA-2-14C was investigated in Parthenocissus tricuspidata crown gall callus tissue. After 48 h incubation, 85-90% of the supplied IAA was taken up by the tissue, and of that taken up, about 45% was conjugated with 5 amino acids. The conjugates found were aspartic and glutamic acid (minor ones) as well as glycine, alanine and valine (major ones). The last 4 are being reported for the 1st time as metabolites of IAA. These conjugates were identified through their chromatographic properties, hydrolysis products and mass spectra. The possible significance of these amino acid conjugates was discussed.