Free tryptophan pool and tryptophan biosynthetic enzymes in Saccharomyces cerevisiae
- 1 January 1976
- journal article
- research article
- Published by Springer Nature in Archiv für Mikrobiologie
- Vol. 107 (2) , 207-214
- https://doi.org/10.1007/bf00446842
Abstract
The free tryptophan pool and the levels of two enzymes of tryptophan biosynthesis (anthranilate synthase and indoleglycerolphosphate synthase) have been determined in a wild type strain of Saccharomyces cerevisiae and in mutants with altered regulatory properties. The tryptophan pool of wild type cells growing in minimal medium is 0.07 μmole per g dry weight. Addition of anthranilate, indole or tryptophan to the medium produces a fifteen- to forty-fold increase in tryptophan pool, but causes no repression of the biosynthetic enzymes. Inclusion of 5-methyltryptophan in the growth medium causes a reduction in growth rate and a derepression of the biosynthetic enzymes, and this is shown here not to be correlated with a decrease in the free tryptophan pool. Mutants with an altered anthranilate synthase showing decreased sensitivity to inhibition by l-tryptophan or by the analogue dl-5-methyltryptophan have a tryptophan pool far higher than the wild type strain, but no repression of indoleglycerolphosphate synthase was observed. Mutants with an anthranilate synthase more sensitive to tryptophan inhibition show a slightly reduced tryptophan pool, but no derepression of indoleglycerolphosphate synthase was found. A mutant with constitutively derepressed levels of the biosynthetic enzymes shows a considerably increased tryptophan pool. Addition of 5-methyltryptophan to the growth medium of non-derepressible mutants causes a decrease in growth rate accompanied by a decrease in the tryptophan pool.Keywords
This publication has 34 references indexed in Scilit:
- Concentrations of intermediary metabolites in yeastBiochimie, 1973
- A sensitive spectrophotometric method for the determination of free or bound tryptophanInternational Journal of Biochemistry, 1972
- Compartmentation in histidine biosynthesisBiochimica et Biophysica Acta (BBA) - General Subjects, 1972
- Method for decryptification of α-glucosidase in yeast with dimethyl sulfoxideAnalytical Biochemistry, 1972
- The Participation of Ornithine and Citrulline in the Regulation of Arginine Metabolism in Saccharomyces cerevisiaeEuropean Journal of Biochemistry, 1970
- GENETIC REGULATORY MECHANISMS IN THE FUNGIAnnual Review of Genetics, 1969
- Regulation of Gene ExpressionAnnual Review of Biochemistry, 1968
- Studies on the mechanism of the tryptophan synthetase reactionBiochimica et Biophysica Acta, 1962
- Metabolic pools and the synthesis of macromoleculesBiochimica et Biophysica Acta, 1959