caa a22 4500 477110665 CHVBK 20180405111608.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00035068 doi (NATIONALLICENCE)springer-10.1007/BF00035068 Identification of enzymes involved in indole-3-acetic acid degradation [Elektronische Daten] [Marianne Olesen, Bjarne Jochimsen] Strains of Bradyrhizobium japonicum with the ability to catabolize indole-3-acetic acid (IAA) and strains of B. japonicum, Rhizobium loti, and Rhizobium galegae, unable to catabolize IAA, were analyzed for enzymes involved in the pathway for IAA degradation. Two enzymes having isatin as substrate were detected. An isatin amidohydrolase catalyzing the hydrolysis of isatin into isatinic acid was found in some B. japonicum strains and in two Rhizobium species, R loti and R. galegae. The enzyme was inducible (4-5-fold) by its substrate, isatin, and the partially purified enzyme from R. loti showed an apparent KM of 11 μM for isatin. A NADPH-dependent isatin reductase was measured in extracts from a strain of B. japonicum lacking the isatin amidohydrolase. The structure of the reaction product, dioxindole was verified by NMR spectroscopy. Isatin reductase activity was also detected in extracts of dry pea seeds, and present in at least two isoforms. A low KM of 10 μM for isatin was found with a partially purified preparation of the pea enzyme. The presence of such an enzyme activity in pea indicates dioxindole and isatin as possible intermediates in IAA degradation in pea. Kluwer Academic Publishers, 1996 amidohydrolase nationallicence Bradyrhizobium japonicum nationallicence IAA nationallicence isatin nationallicence pea nationallicence reductase nationallicence Rhizobium nationallicence Olesen Marianne Department of Molecular Biology, University of Aarhus, DK 8000, Aarhus, Denmark aut Jochimsen Bjarne Department of Molecular Biology, University of Aarhus, DK 8000, Aarhus, Denmark aut Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl 186/1(1996-09-01), 143-149 0032-079X 186:1<143 1996 186 11104 https://doi.org/10.1007/BF00035068 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00035068 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Olesen Marianne Department of Molecular Biology, University of Aarhus, DK 8000, Aarhus, Denmark aut NATIONALLICENCE 700 1- Jochimsen Bjarne Department of Molecular Biology, University of Aarhus, DK 8000, Aarhus, Denmark aut NATIONALLICENCE 773 0- Plant and Soil Kluwer Academic Publishers; http://www.wkap.nl/ 186/1(1996-09-01), 143-149 0032-079X 186:1<143 1996 186 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer