Print Email Facebook Twitter Alleviation of feedback inhibition in Saccharomyces cerevisiae aromatic amino acid biosynthesis: Quantification of metabolic impact Title Alleviation of feedback inhibition in Saccharomyces cerevisiae aromatic amino acid biosynthesis: Quantification of metabolic impact Author Luttik, M.A.H. (TU Delft BT/Industriele Microbiologie) Vuralhan, Z (TU Delft BT/Industriele Microbiologie) Suir, E (TU Delft BT/Industriele Microbiologie) Braus, G.H. (Georg-August-University) Pronk, J.T. (TU Delft BT/Biotechnologie) Daran, J.G. (TU Delft BT/Industriele Microbiologie) Department BT/Biotechnologie Date 2008 Abstract A quantitative analysis of the impact of feedback inhibition on aromatic amino acid biosynthesis was performed in chemostat cultures of Saccharomyces cerevisiae. Introduction of a tyrosine-insensitive allele of ARO4 (encoding 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase) caused a three-fold increase of intracellular phenylalanine and tyrosine concentrations. These amino acids were not detected extracellularly. However, an over 100-fold increase of the extracellular levels of phenylacetate, phenylethanol and their para-hydroxyl analogues was observed. The total increase of the flux through the aromatic pathway was estimated to be over four-fold. Individual overexpression of either the wild-type or feedback insensitive allele of ARO7 (encoding chorismate mutase had no significant impact. However when they were combined with the Tyr-insensitive ARO4 allele in combination with the Tyr-insensitive ARO4 allele, extracellular concentrations of aromatic compounds were increased by over 200-fold relative to the reference strain, corresponding to a 4.5-fold increase of the flux through the aromatic amino acid biosynthesis pathway. Elimination of allosteric control on these two key reactions in aromatic amino acid metabolism significantly affected intracellular concentrations of several non-aromatic amino acids. This broader impact of amino acid biosynthesis presents a challenge in rational optimization of the production of specific amino acids and derived flavour compounds. To reference this document use: http://resolver.tudelft.nl/uuid:43d6a881-f93a-4c6d-8daf-0495373a1aef DOI https://doi.org/10.1016/j.ymben.2008.02.002 Embargo date 2008-08-20 ISSN 1096-7176 Source Metabolic Engineering, 10 (3-4), 141-153 Bibliographical note Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2008 M.A.H. Luttik, Z Vuralhan, E Suir, G.H. Braus, J.T. Pronk, J.G. Daran Files PDF 1-s2.0-S1096717608000025-main.pdf 878.2 KB Close viewer /islandora/object/uuid:43d6a881-f93a-4c6d-8daf-0495373a1aef/datastream/OBJ/view