Miniaturized and automated adaptive laboratory evolution: Evolving Corynebacterium glutamicum towards an improved d-xylose utilization

Andreas Radek, Niklas Tenhaef, Moritz Fabian Müller, Christian Brüsseler, Wolfgang Wiechert, Jan Marienhagen, Tino Polen, Stephan Noack*

*Corresponding author for this work

Abstract

Adaptive Laboratory Evolution (ALE) is increasingly being used as a technique for untargeted strain optimization. This work aimed at developing an automated and miniaturized ALE approach based on repetitive batch cultivations in microtiter plates. The new method is applied to the recently published strain Corynebacterium glutamicum pEKEx3-xylXABCDCc, which is capable of utilizing d-xylose via the Weimberg (WMB) pathway. As a result, the significantly improved strain WMB2evo was obtained, showing a specific growth rate of 0.26h-1 on d-xylose as sole carbon and energy source. WMB2evo grows stable during lab-scale bioreactor operation, demonstrating the high potential of this strain for future biorefinery applications. Genome sequencing of cell samples from two different ALE processes revealed potential key mutations, e.g. in the gene cg0196 (encoding for the transcriptional regulator IolR of the myo-inositol metabolism). These findings open up new perspectives for the rational engineering of C. glutamicum towards improved d-xylose utilization.

Original languageEnglish
JournalBioresource technology
Volume245
Issue numberPt B
Pages (from-to)1377-1385
Number of pages9
ISSN0960-8524
DOIs
Publication statusPublished - 2017
Externally publishedYes

DFG Research Classification Scheme

  • 2.11-01 Biochemistry

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