Indolepyruvate pathway for indole-3-acetic acid biosynthesis in Bradyrhizobium elkanii

Kiwamu Minamisawa, Ken Ichiro Ogawa, Hideyuki Fukuhara, Jinichiro Koga

Research output: Contribution to journalArticlepeer-review

19 Citations (Scopus)


Indole-3-acetaldehyde (IAAld) was detected in the culture supernatant of Bradyrhizobium elkanii. Deuterium-labelled L-tryptophan (Trp) was incorporated into IAAld and indole-3-acetic acid (IAA), suggesting that B. elkanii produces IAA via IAAld from Trp. In B. elkanii cell suspension, indole-3-pyruvic acid (IPyA) was converted to IAAld, and exogenously added IAAld was rapidly converted to IAA. Furthermore, the activity of indolepyruvate decarboxylase (IPDC), which catalyzes the decarboxylation of IPyA to produce IAAld and is a key enzyme for IPyA pathway, was detected in B. elkanii cell-free extract. The IPDC activity depended on Mg2+ and thiamine pyrophosphate, cofactors of decarboxylation. This mounting evidence strongly suggests that IAA synthesis occurs via IPyA pathway (Trp → IPyA → IAAld → IAA) in B. elkanii.

Original languageEnglish
Pages (from-to)449-453
Number of pages5
JournalPlant and Cell Physiology
Issue number4
Publication statusPublished - 1996 Jun


  • Bradyrhizobium elkanii
  • Indole-3- acetaldehyde
  • Indole-3-acetic acid (IAA)
  • Indolepyruvate decarboxylase


Dive into the research topics of 'Indolepyruvate pathway for indole-3-acetic acid biosynthesis in Bradyrhizobium elkanii'. Together they form a unique fingerprint.

Cite this