Enhanced glutathione production by evolutionary engineering of Saccharomyces cerevisiae strains.
Glutathione is an important natural tripeptide mainly used because of its antioxidative properties. Commercial glutathione is microbially synthesized by yeasts and the growing demand requires the development of new production strains. An adaptive laboratory evolution strategy using acrolein as a selection agent was employed to obtain strains with an enhanced glutathione accumulation phenotype accompanied by an acrolein resistance phenotype. Two particularly interesting isolates were obtained: one with a high volumetric productivity for glutathione reaching 8.3 mg(glutathione)/L h, which is twice as high as the volumetric productivity of its parental strain. This strain reached an elevated intracellular glutathione content of 3.9%. A second isolate with an even higher acrolein tolerance exhibited a lower volumetric productivity of 5.8 mg(glutathione)/L h due to a growth phenotype. However, this evolved strain accumulated glutathione in 3.3-fold higher concentration compared to its parental strain and reached a particularly high glutathione content of almost 6%. The presented results demonstrate that acrolein is a powerful selection agent to obtain high glutathione accumulation strains in an adaptive laboratory evolution experiment.
Department of Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Austria.|Austrian Centre of Industrial Biotechnology (ACIB GmbH), Vienna, Austria.
Anett
A
Patzschke
Department of Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Austria. Matthias.steiger@boku.ac.at.|Austrian Centre of Industrial Biotechnology (ACIB GmbH), Vienna, Austria. Matthias.steiger@boku.ac.at.
Matthias G
MG
Steiger
Organobalance GmbH, Berlin, Germany.
Caterina
C
Holz
Organobalance GmbH, Berlin, Germany.
Christine
C
Lang
Department of Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Austria.|Austrian Centre of Industrial Biotechnology (ACIB GmbH), Vienna, Austria.
Diethard
D
Mattanovich
Department of Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Austria.|Austrian Centre of Industrial Biotechnology (ACIB GmbH), Vienna, Austria.
Michael
M
Sauer
D019149:Bioreactors; D019020:Directed Molecular Evolution; D000431:Ethanol; D005978:Glutathione / Q000032:analysis / Q000378:metabolism*; D060847:Metabolic Engineering / Q000379:methods*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*
D000431:Ethanol; D005978:Glutathione
Acrolein; Adaptive laboratory evolution; Glutathione; Glutathione disulfide; γ-glutamyl-L-cysteinylglycine