Adaptively evolved yeast mutants on galactose show trade-offs in carbon utilization on glucose
Journal article, 2013

Adaptive evolution offers many opportunities in metabolic engineering; however, several constraints still exist as evolutionary trade-offs may impose collateral cost to obtain new traits. The application of adaptive evolution for strains development could be further improved by elucidating the molecular mechanisms. In this study, adaptively evolved yeast mutants with improved galactose utilization ability showed impaired glucose utilization. The molecular genetic basis of this trade-off was investigated using a systems biology approach. Transcriptional and metabolic changes resulting from the improvement of galactose utilization were found maintained during growth on glucose. Moreover, glucose repression related genes showed conserved expression patterns during growth on both sugars. Mutations in the RAS2 gene that were identified as beneficial for galactose utilization in evolved mutants exhibited significant correlation with attenuation of glucose utilization. These results indicate that antagonistic pleiotropy is the dominant mechanism in the observed trade-off, and it is likely realized by changes in glucose signaling.


Systems biology



Metabolic engineering

Galactose metabolism


Evolutionary trade-off




Kuk-ki Hong

Chalmers, Chemical and Biological Engineering, Life Sciences

Jens B Nielsen

Chalmers, Chemical and Biological Engineering, Life Sciences

Metabolic Engineering

1096-7176 (ISSN) 1096-7184 (eISSN)

Vol. 16 1 78-86

Industrial Systems Biology of Yeast and A. oryzae (INSYSBIO)

European Commission (EC) (EC/FP7/247013), 2010-01-01 -- 2014-12-31.

Areas of Advance

Life Science Engineering (2010-2018)

Subject Categories

Chemical Sciences



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