| abstract |
Described herein are microorganisms, in particular yeast, which have been transformed with one or more expression construct(s) for i) the overexpression of the native genes encoding xylulose kinase (XKS1), transaldolase (TAL1), transketolase 1 (TKL1) and transketolase 2 (TKL2) and ii) the expression of a functional heterologous gene encoding a xylose isomerase (XI), where the xylose isomerase (XI) gene is derived from a microorganism selected from the group consisting of T. neapolitana, A. andensis and C. clariflavum. Also described herein are expression constructs, methods for fermenting pentose sugars using the microorganisms and methods for producing such microorganisms. |