The invention relates to a process for the production of ethanol from a composition comprising at least glucose comprising fermenting said composition in the presence of a recombinant yeast; and recovering the ethanol, wherein said yeast comprises one or more genes coding for an enzyme having glycerol dehydrogenase activity, one or more genes coding for an enzyme having dihydroxyacetone kinase activity (E.C. 2.7.1.28 and/or E.C. 2.7.1.29); one or more genes coding for an enzyme in an acetyl-CoA-production pathway and one or more genes coding for an enzyme having at least NAD+ dependent acetylating acetaldehyde dehydrogenase activity (EC 1.2.1.10 or EC 1.1.1.2), and optionally one or more genes coding for a glycerol transporter, wherein the composition comprises an amount of undissociated acetic acid of 10 mM or less. A recombinant yeast having the genes as described above is particularly sensitive towards acetic acid, and the ethanol yield rapidly decreases when the composition contains more than 10 mM undissociated acetic acid.

The invention describes a process for the production of ethanol from a composition comprising glucose and between 50 M and 100 mM acetic acid, said process comprising fermenting said composition in the presence of a recombinant yeast which is capable to convert acetic acid anaerobically; maintaining the amount of undissociated acetic acid at a value of at least 50 M; and recovering the ethanol. Said process is useful for both starch and cellulosic based, acetic acid containing hydrolysates and advantageously results in a greater consumption of acetic acid and thus higher ethanol yields.

The present disclosure is intended to reduce the amount of glycerin produced as a byproduct in ethanol fermentation to a significant extent using a transgenic yeast comprising a gene having the pentose assimilating ability and encoding glycerin dehydrogenase having a mitochondrial transport signal introduced thereinto.

Polypeptide scaffolds comprising enzymatic proteins are provided. The enzymatic polypeptide scaffolds comprise heterologous enzymes to form a heterologous metabolic pathway, and can be targeted to a substrate through a surface anchoring domain. The enzymatic polypeptide scaffolds leverage the high specificity and affinity protein/protein interaction between the cohesins and dockerins of microorganismal cellulosomes to form custom enzymatic arrays.

The invention relates to a recombinant cell, preferably a yeast cell comprising one or more genes coding for an enzyme having glycerol dehydrogenase activity, one or more genes coding dihydroxyacetone kinase (E.C. 2.7.1.28 and/or E.C. 2.7.1.29); one or more genes coding for an enzyme in an acetyl-CoA-production pathway and one or more genes coding for an enzyme having at least NAD.sup.+ dependent acetylating acetaldehyde dehydrogenase activity (EC 1.2.1.10 or EC 1.1.1.2), and optionally one or more genes coding for a glycerol transporter. This cell can be used for the production of ethanol and advantageously produces little or no glycerol.

The present disclosure relates to a mutant microorganism in which a glycerol catabolic pathway and a 1,3-PDO biosynthetic pathway are introduced into a microorganism incapable of using glycerol as a carbon source, and a method of producing 1,3-PDO using the same. According to the present disclosure, it is possible to produce 1,3-PDO while growing a mutant microorganism having 1,3-PDO production ability by using the inexpensive raw material glycerol as a single carbon source. Thus, the present disclosure is useful for the economical production of 1,3-PDO.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

Cell that is genetically modified comprising: a) one or more nucleotide sequence encoding a NAD.sub.+-dependent acetylating acetaldehyde dehydrogenase (E.C. 1.2.1.10); b) one or more nucleotide sequence encoding a acetyl-CoA synthetase (E.C. 6.2.1.1); c) one or more nucleotide sequence encoding a glycerol dehydrogenase (E.C. 1.1.1.6); and d) one or more nucleotide sequence encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 or E.C. 2.7.1.29).

Cell that is genetically modified comprising: a) one or more nucleotide sequence encoding a NAD+-dependent acetylating acetaldehyde dehydrogenase (E.C. 1.2.1.10); b) one or more nucleotide sequence encoding a acetyl-CoA synthetase (E.C. 6.2.1.1); c) one or more nucleotide sequence encoding a glycerol dehydrogenase (E.C. 1.1.1.6); and d) one or more nucleotide sequence encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 or E.C. 2.7.1.29).