The present invention relates to a yeast cell that is genetically modified comprising: a) a disruption of one or more aldehyde dehydrogenase (E.C:1.2.1.4) native to the yeast; b) one or more nucleotide sequence encoding a heterologous NAD.sub.+-dependent acetylating acetaldehyde dehydrogenase (E.C. 1.2.1.10); c) one or more nucleotide sequence encoding a homologous or heterologous acetyl-CoA synthetase (E.C. 6.2.1.1); and d) a modification that leads to reduction of glycerol 3-phosphate phosphohydrolase (E.C. 3.1.3.21) and/or glycerol 3-phosphate dehydrogenase (E.C. 1.1.1.8 or E.C. 1.1.5.3) activity, native to the yeast.

The present specification relates to a transformed yeast strain capable of simultaneously utilizing xylose and glucose as carbon sources, a preparation method thereof and a biofuel production method using the same. The transformed yeast strain transforms a wild-type yeast strain incapable of using xylose as a carbon source and simultaneously convert glucose and xylose, thereby enabling high yield production of a biofuel. The economics and sustainability of the biofuel and biomaterial production processes can be highly enhanced by providing a strain which can easily be converted to a strain capable of producing a biofuel/material in a high yield through an additional modification.

There is provided an engineered host cells comprising (a) one or more mutations in one or more endogenous genes encoding a protein associated with iron metabolism; and (b) at least one gene encoding a polypeptide having xylose isomerase activity, and methods of their use thereof.

The present invention relates to processes for producing ethanol comprising saccharifying cellulosic or starch-containing material and fermenting the saccharified material with a fermenting microorganism to produce ethanol. The fermenting organism is Saccharomyces cerevisiae strain MBG5151 (deposited under Accession No. Y-67971 at the Agricultural Research Service Culture Collection (NRRL), Illinois 61604 U.S.A.), Saccharomyces cerevisiae strain MBG5248 (deposited under Accession No. Y-68015 at the Agricultural Research Service Culture Collection (NRRL), Illinois 61604 U.S.A.) or a fermenting organism that has properties that the same or about the same as that of Saccharomyces cerevisiae MBG5151 or MBG5248.

Disclosed is a method for promoting extracellular expression of proteins in B. subtilis using cutinase, which belongs to the technical fields of genetic engineering, enzyme engineering and microbial engineering. It teaches co-expressing a cutinase mutant and a target protein in B. subtilis to promote extracellular expression of the target protein which is naturally located inside cells. The target protein includes xylose isomerase, 4,6-α-glucosyltransferase, 4-α-glucosyltransferase, trehalose synthase, branching enzyme and the like. The invention can achieve extracellular expression of intracellularly localized target protein, improve the production efficiency, reduce the production cost and simplify the subsequent extraction process.

The present disclosure provides methods for genetically modifying microbes to produce a microbe capable of simultaneous consumption of xylose and glucose to increase the productivity output of desired chemical products. The disclosure further provides modified bacteria that are capable of simultaneous consumption of xylose and glucose, and compositions comprising the microbes.

There is provided a method for treating or reducing the effects of fructose intolerance and health problems associated with excessive fructose intake by administration of glucose isomerase. Other embodiments are also disclosed.

The present invention provides for a nucleic acid encoding an isomerase and uses of the isomerase for bioconversion of sugar substrates. The invention represents an advancement in the field of enzyme engineering and discloses a modified nucleic acid for achieving optimum expression of a protein having isomerase activity in a heterologous host. The invention also discloses vectors carrying the modified nucleic acid and recombinant host cells carrying the vectors. The invention also discloses the process for producing a recombinant host cell, process for production of the recombinant enzyme and the process for bioconversion of sugars into their respective isomers using the recombinant protein.

There is provided a method for treating or reducing the effects of fructose intolerance and health problems associated with excessive fructose intake by administration of glucose isomerase. Other embodiments are also disclosed.

Provided are excellent L-arabinose metabolic genes that function in yeasts. Provided is an L-arabinose metabolic gene cluster including an L-arabinose isomerase gene specified by a predetermined SEQ ID, an L-ribulokinase gene specified by a predetermined SEQ ID, and an L-ribulose-5-phosphate-4-epimerase gene specified by a predetermined SEQ ID.