Engineering of an endogenous hexose transporter into a specific D-xylose transporter facilitates glucose-xylose co-consumption in Saccharomyces cerevisiaeNijland, J. G., Shin, H. Y., de Jong, R. M., De Waal, P. P., Klaassen, P. & Driessen, A. J. M., 29-Nov-2014, In : Biotechnology for Biofuels. 7, 168, 11 p., 168.
Research output: Contribution to journal › Article › Academic › peer-review
Background: Engineering of Saccharomyces cerevisiae for the simultaneous utilization of hexose and pentose sugars is vital for cost-efficient cellulosic bioethanol production. This yeast lacks specific pentose transporters and depends on endogenous hexose transporters for low affinity pentose uptake. Consequently, engineered xylose-fermenting yeast strains first utilize D-glucose before D-xylose can be transported and metabolized.
Results: We have used an evolutionary engineering approach that depends on a quadruple hexokinase deletion xylose-fermenting S. cerevisiae strain to select for growth on D-xylose in the presence of high D-glucose concentrations. This resulted in D-glucose-tolerant growth of the yeast of D-xylose. This could be attributed to mutations at N367 in the endogenous chimeric Hxt36 transporter, causing a defect in D-glucose transport while still allowing specific uptake of D-xylose. The Hxt36-N367A variant transports D-xylose with a high rate and improved affinity, enabling the efficient co-consumption of D-glucose and D-xylose.
Conclusions: Engineering of yeast endogenous hexose transporters provides an effective strategy to construct glucose-insensitive xylose transporters that are well integrated in the carbon metabolism regulatory network, and that can be used for efficient lignocellulosic bioethanol production.
|Number of pages||11|
|Journal||Biotechnology for Biofuels|
|Publication status||Published - 29-Nov-2014|
- Sugar transporter, Xylose transporter, Evolutionary engineering, Bioethanol, Yeast, ESCHERICHIA-COLI, FERMENTATION, CATABOLISM, EXPRESSION, BIOFUELS, STRAIN, GENES, KEY