Metabolism of tryptophan by Pseudomonas aureofaciens and its relationship to pyrrolnitrin biosynthesis

J Gen Microbiol. 1980 Dec;121(2):465-71. doi: 10.1099/00221287-121-2-465.


Studies on the metabolism of tryptophan in Pseudomonas aureofaciens ATCC 15926 revealed different metabolic routes for the L- and D-isomer besides the biosynthetic pathway for pyrrolnitrin synthesis. L-Tryptophan catabolism follows the aromatic route via anthranilic acid. Tryptophan 2,3-dioxygenase were induced by L-tryptophan. Kynureninase and anthranilate 1,2-dioxygenase were induced by L-tryptophan, L-kynurenine and anthranilic acid. Anthranilate 1,2-dioxygenase was absent from a mutant strain of P. aureofaciens ATCC 19526 which produced about 30-fold increased amounts of pyrrolnitrin. The Km values of tryptophan 2,3-dioxygenase and kynureninase did not differ substantially between the two strains. Kynurenine 3-monooxygenase, 3-hydroxyanthranilate 3,4-dioxygenase, tryptophanase and indolyl-3-alkane alpha-hydroxylase activities were not detected. D- and L-tryptophan were converted to indole-3-acetic acid. This additional catabolic pathway was well as tryptophan racemase activity was constitutive and present in both strains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / biosynthesis*
  • Enzyme Induction
  • Glycerol / metabolism
  • Indoleacetic Acids / metabolism
  • Kynurenine / metabolism
  • Pseudomonas / metabolism*
  • Pyrrolnitrin / biosynthesis*
  • Tryptophan / metabolism*
  • Tryptophan Oxygenase / metabolism
  • ortho-Aminobenzoates / metabolism


  • Antifungal Agents
  • Indoleacetic Acids
  • ortho-Aminobenzoates
  • Kynurenine
  • Tryptophan
  • Tryptophan Oxygenase
  • Pyrrolnitrin
  • Glycerol