IUBMB Enzyme Nomenclature


Accepted name: indole-3-acetaldehyde oxidase

Reaction: (indol-3-yl)acetaldehyde + H2O + O2 = (indol-3-yl)acetate + H2O2

Other name(s): indoleacetaldehyde oxidase; IAAld oxidase; AO1; indole-3-acetaldehyde:oxygen oxidoreductase

Systematic name: (indol-3-yl)acetaldehyde:oxygen oxidoreductase

Comments: A hemoprotein. This enzyme is an isoform of aldehyde oxidase (EC It has a preference for aldehydes having an indole-ring structure as substrate [6,7]. It may play a role in plant hormone biosynthesis as its activity is higher in the auxin-overproducing mutant, super-root1, than in wild-type Arabidopsis thaliana [7]. While (indol-3-yl)acetaldehyde is the preferred substrate, it also oxidizes indole-3-carbaldehyde and acetaldehyde, but more slowly. The enzyme from maize contains FAD, iron and molybdenum [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 66082-22-2


1. Bower, P.J., Brown, H.M. and Purves, W.K. Cucumber seedling indoleacetaldehyde oxidase. Plant Physiol. 61 (1978) 107-110.

2. Miyata, S., Suzuki, Y., Kamisaka, S. and Masuda, Y. Indole-3-acetaldehyde oxidase of pea-seedlings. Physiol. Plant. 51 (1981) 402-406.

3. Rajagopal, R. Metabolism of indole-3-acetaldehyde. III. Some characteristics of the aldehyde oxidase of Avena coleoptiles. Physiol. Plant. 24 (1971) 272-281.

4. Koshiba, T., Saito, E., Ono, N., Yamamoto, N. and Sato, M. Purification and properties of flavin- and molybdenum-containing aldehyde oxidase from coleoptiles of maize. Plant Physiol. 110 (1996) 781-789. [PMID: 12226218]

5. Koshiba, T. and Matsuyama, H. An in vitro system of indole-3-acetic acid formation from tryptophan in maize (Zea mays) coleoptile extracts. Plant Physiol. 102 (1993) 13191324. [PMID: 12231908]

6. Sekimoto, H., Seo, M., Kawakami, N., Komano, T., Desloire, S., Liotenberg, S., Marion-Poll, A., Caboche, M., Kamiya, Y. and Koshiba, T. Molecular cloning and characterization of aldehyde oxidases in Arabidopsis thaliana. Plant Cell Physiol. 39 (1998) 433442. [PMID: 9615466]

7. Seo, M., Akaba, S., Oritani, T., Delarue, M., Bellini, C., Caboche, M. and Koshiba, T. Higher activity of an aldehyde oxidase in the auxin-overproducing superroot1 mutant of Arabidopsis thaliana. Plant Physiol. 116 (1998) 687693. [PMID: 9489015]

[EC created 1984, modified 2004]

Return to EC 1.2.3 home page
Return to EC 1.2 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page