The invention is related to an inducible promoter for improved and regulated gene expression, useful in synthetic biology and metabolic engineering. In particular, the present invention relates to a nucleotide sequence comprising the regulatory regions of an erythritol- and erythrulose-inducible promoter in yeast and uses thereof in an expression system thus allowing an improved and regulated gene expression and production of gene product.

The present invention relates to a recombinant microbial host for the production of xylitol, the recombinant microbial host containing a nucleic acid sequence encoding an NAD+-specific D-arabitol 4-oxidoreductase (EC 1.1.1.11) using D-arabitol as substrate and producing D-xylulose as product, and a nucleic acid sequence encoding an NADPH-specific xylitol dehydrogenase using D-xylulose as substrate and producing xylitol as product.

The present invention provides methods and compositions suitable for use in the isomerization of xylose to xylulose, as well as methods and compositions suitable for use in the conversion of xylose to xylitol and xylulose, including nucleic acid constructs, recombinant fungal host cells, and related materials.

Presented herein are oleaginous strains of yeast such as Saccharomyces cerevisiae that have been modified to allow for xylose utilization. Such strains are also modified to allow for higher lipid accumulation utilizing a broad range of sugar monomers such as those released during pretreatment and enzymatic saccharification of lignocellulosic biomass. Methods of producing lipids and ethanol using these yeast strains are also disclosed.

The present invention relates to a method of preparing a strain of sugar fermenting Saccharomyces cerevisiae with capability to ferment xylose, wherein said method comprises different procedural steps. The method comprises mating a first sporulated Saccharomyces cerevisiae strain with a second Saccharomyces cerevisiae haploid strain. Thereafter, screening for mated cells is performed, growing such mated cells, and verifying that mated cells exhibit basic morphology by microscopic inspection. Thereafter, creation of a mixture of the mated cells is performed, subjecting the mixture to continuous chemostat lignocellulose cultivation and obtaining the sugar fermenting Saccharomyces cerevisiae cells with capability to ferment xylose is performed. The invention also comprises strains obtained by said method.

Recombinant yeasts comprising recombinant xylose reductase, xylitol dehydrogenase, and/or xylulokinase genes and methods of using same, such as for producing ethanol from xylose-containing feedstocks.

Disclosed herein are genetically engineered yeast cells capable of producing xylitol. The engineered yeast cell may comprise an exogenous polynucleotide sequence encoding a xylitol-phosphate dehydrogenase (XPDH) enzyme comprising a sequence at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or 100% identical to at least one of SEQ ID NOs: 12-15, 28-31, or 33.

Disclosed herein are genetically engineered yeast cells capable of producing xylitol. The engineered yeast cell may comprise an exogenous polynucleotide sequence encoding a sugar phosphatase enzyme comprising a sequence at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or 100% identical to at least one of SEQ ID NOs: 8 and 20.

Provided herein are compositions and methods for the fermentative production of 2,3-butanediol (2,3-BDO), compositions and methods for making methyl ethyl ketone (MEK), and methods of inducing drought tolerance in plants.