Abstract
The metabolism of several indole compounds in the gut of the bug Lygus disponsi was investigated. Al the indole compounds were more or less metabolized in the gut. The metabolic patterns of IAA, indole-3-propionic acid and indole-3-butyric acid with -(CH2)n-COOH in the side chain were similar to one another. Also, the compounds with -CH2- in the side chain (indole-3-ethanol, tryptamine, serotonine, gramine, indol-3acetonitrile and indole -3-acetaldehyde) were converted to several metabolites. The metabolites of indole-3-butyric acid had auxin activity. The metabolites that appeared in the excreta of the IAA-feeding bugs were probably the substances conjugated by attaching some molecules to hte side chain of indole nucleus. The significance of the auxin metabolism by the bug is also discussed.
