All IAA derivatives used in this study (indole-3-acetic acid, 3-(2-hydroxyethyl)indole, ethyl-3-indole-acetate, 3-(3-hydroxypropyl)indole, 3-indoleacetonitrile, indole-3-acetamide, indole-3-butyric acid, DL-indole-3-lactic acid, indole-3-propionic acid, tryptamine, indole-3-acrycil acid and indole-3-carboxylic acid) and H218O were purchased from Sigma-Aldrich. All cloning and protein expression reagents were from ThermoFisher Scientific (Vilnius, Lithuania). All other reagents used in this study were of analytical or higher grade.
Caballeronia glathei strain DSM50014 was obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ), Braunschweig, Germany. This strain was routinely cultivated in M1 medium (5 g L−1 peptone, 3 g L−1 meat extract, pH 7). For the IAA assimilation experiments, C. glathei DSM50014 was cultivated in M9 medium (3.5 g L−1 Na2HPO4, 1.5 g L−1 KH2PO4, 2.5 g L−1 NaCl, 0.2 g L−1 MgSO4, 0.01 g L−1 CaCl2). Escherichia coli strains used in this study are listed inSupplementary Table S2 . All E. coli strains were cultivated in LB medium. Ampicillin (50 μg mL−1) and streptomycin (30 μg mL−1) were added when necessary.
Caballeronia glathei strain DSM50014 was obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ), Braunschweig, Germany. This strain was routinely cultivated in M1 medium (5 g L−1 peptone, 3 g L−1 meat extract, pH 7). For the IAA assimilation experiments, C. glathei DSM50014 was cultivated in M9 medium (3.5 g L−1 Na2HPO4, 1.5 g L−1 KH2PO4, 2.5 g L−1 NaCl, 0.2 g L−1 MgSO4, 0.01 g L−1 CaCl2). Escherichia coli strains used in this study are listed in