Abstract: | The cell pools of tryptophan and anthranilate, the excretion of indole-containing metabolites, and the levels of the enzymes of aromatic amino acid biosynthesis have been determined in regulatory mutants of Hansenula henricii. The strain Hg 48-2-M8 produces indoles with a maximum specific productivity of 0.37 mg/g · h at a maximum specific production value of 21 mg/g dry cell weight. This methyl-tryptophan resistant mutant possess an anthranilate synthase, whose inhibition by tryptophan is reduced. The best conditions for production of indoles are the following: 1% glucose as C-source; ammonium as N-source; pH value smaller than 4. We found that under various growth conditions 25–60% synthesized indole-containing metabolites consists of tryptophan. |