The myo-inositol/proton symporter IolT1 contributes to d-xylose uptake in Corynebacterium glutamicum

Christian Brüsseler, Andreas Radek, Niklas Tenhaef, Karin Krumbach, Stephan Noack, Jan Marienhagen*

*Corresponding author for this work


Corynebacterium glutamicum has been engineered to utilize d-xylose as sole carbon and energy source. Recently, a C. glutamicum strain has been optimized for growth on defined medium containing d-xylose by laboratory evolution, but the mutation(s) attributing to the improved-growth phenotype could not be reliably identified. This study shows that loss of the transcriptional repressor IolR is responsible for the increased growth performance on defined d-xylose medium in one of the isolated mutants. Underlying reason is derepression of the gene for the glucose/myo-inositol permease IolT1 in the absence of IolR, which could be shown to also contribute to d-xylose uptake in C. glutamicum. IolR-regulation of iolT1 could be successfully repealed by rational engineering of an IolR-binding site in the iolT1-promoter. This minimally engineered C. glutamicum strain bearing only two nucleotide substitutions mimics the IolR loss-of-function phenotype and allows for a high growth rate on d-xylose-containing media (µmax = 0.24 ± 0.01 h-1).

Original languageEnglish
JournalBioresource technology
Pages (from-to)953-961
Number of pages9
Publication statusPublished - 02.2018
Externally publishedYes

DFG Research Classification Scheme

  • 201-01 Biochemistry


Dive into the research topics of 'The myo-inositol/proton symporter IolT1 contributes to d-xylose uptake in Corynebacterium glutamicum'. Together they form a unique fingerprint.

Cite this