Identification and biochemical characterization of an Arabidopsis indole-3-acetic acid glucosyltransferase

J Biol Chem. 2001 Feb 9;276(6):4350-6. doi: 10.1074/jbc.M006185200. Epub 2000 Oct 20.


Biochemical characterization of recombinant gene products following a phylogenetic analysis of the UDP-glucosyltransferase (UGT) multigene family of Arabidopsis has identified one enzyme (UGT84B1) with high activity toward the plant hormone indole-3-acetic acid (IAA) and three related enzymes (UGT84B2, UGT75B1, and UGT75B2) with trace activities. The identity of the IAA conjugate has been confirmed to be 1-O-indole acetyl glucose ester. A sequence annotated as a UDP-glucose:IAA glucosyltransferase (IAA-UGT) in the Arabidopsis genome and expressed sequence tag data bases given its similarity to the maize iaglu gene sequence showed no activity toward IAA. This study describes the first biochemical analysis of a recombinant IAA-UGT and provides the foundation for future genetic approaches to understand the role of 1-O-indole acetyl glucose ester in Arabidopsis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / enzymology*
  • Base Sequence
  • Chromatography, High Pressure Liquid
  • DNA Primers
  • Gas Chromatography-Mass Spectrometry
  • Glycosyltransferases / antagonists & inhibitors
  • Glycosyltransferases / genetics
  • Glycosyltransferases / metabolism*
  • Indoleacetic Acids / metabolism*
  • Kinetics
  • Phylogeny
  • Substrate Specificity


  • DNA Primers
  • Indoleacetic Acids
  • indoleacetic acid
  • Glycosyltransferases