The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to T354, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present invention relates to a new L-arabinose assimilation pathway and uses thereof. In particular, the present invention relates to polypeptides exhibiting L-arabinose isomerase, L-ribulokinase or L-ribulose-5-phosphate-4-epimerase activity, and recombinant host cells expressing said polypeptides. The present invention also relates to a method of producing a fermentation product, preferably ethanol, from an arabinose containing substrate, using a polypeptide or a host cell of the invention.

The present application discloses the identification of the novel K. marxianus xylose transporter genes KHT105 and RAG4, as well as the identification of a novel set of I. orientalis pentose phosphate pathway genes The present application further discloses a series of genetically modified yeast cells comprising various combinations of arabinose fermentation pathways, xylose fermentation pathways, pentose phosphate pathways, and/or xylose transporter genes, and methods of culturing these cells to produce ethanol in fermentation media containing xylose.

The present invention relates to polypeptides which are Gal2 variants comprising at least one amino acid substitution at a position corresponding to M435, and optionally further amino acid substitution(s). The present invention further relates to nucleic acid molecules encoding the polypeptides and to host cells containing said nucleic acid molecules. The present invention further relates to a method for the production of bioethanol and/or other bio-based compounds, comprising the expression of said nucleic acid molecules, preferably in said host cells. The present invention also relates to the use of the polypeptides, nucleic acids molecule or host cells for the production of bioethanol and/or other bio-based compounds, and/or for the recombinant fermentation of biomaterial containing pentose(s), preferably D-xylose and/or L-arabinose.

The present disclosure relates to D-xylulose 4-epimerase, mutants thereof, and uses thereof. Specifically, the present disclosure relates to a polypeptide having D-xylulose 4-epimerase activity, a method for preparing said polypeptide, and use of said polypeptide in the preparation of L-pentose using D-xylose or D-xylulose as a raw material. Compared with the traditional preparation method in the prior art, the new method for preparing L-pentose discovered in the present disclosure has simpler production process and reduces the cost of producing L-pentose.