Described is a method for the conversion of 3-methylcrotonyl-CoA into 3-hydroxy-3-methylbutyric acid comprising the steps of: (a) enzymatically converting 3-methylcrotonyl-CoA into 3-hydroxy-3-methylbutyryl-CoA; and (b) further enzymatically converting the thus produced 3-hydroxy-3-methylbutyryl-CoA into 3-hydroxy-3-methylbutyric acid wherein the enzymatic conversion of 3-hydroxy-3-methylbutyryl-CoA into 3-hydroxy-3-methylbutyric acid according to step (b) is achieved by first converting 3-hydroxy-3-methylbutyryl-CoA into 3-hydroxy-3-methylbutyryl phosphate and then subsequently converting the thus produced 3-hydroxy-3-methylbutyryl phosphate into 3-hydroxy-3-methylbutyric acid.

The present invention provides for a mechanism to completely replace the electron accepting function of glycerol formation with an alternative pathway to ethanol formation, thereby reducing glycerol production and increasing ethanol production. In some embodiments, the invention provides for a recombinant microorganism comprising a down-regulation in one or more native enzymes in the glycerol-production pathway. In some embodiments, the invention provides for a recombinant microorganism comprising an up-regulation in one or more enzymes in the ethanol-production pathway.

The invention provides non-naturally occurring microbial organisms containing a fatty alcohol, fatty aldehyde or fatty acid pathway, wherein the microbial organisms selectively produce a fatty alcohol, fatty aldehyde or fatty acid of a specified length. Also provided are non-naturally occurring microbial organisms having a fatty alcohol, fatty aldehyde or fatty acid pathway, wherein the microbial organisms further include an acetyl-CoA pathway. In some aspects, the microbial organisms of the invention have select gene disruptions or enzyme attenuations that increase production of fatty alcohols, fatty aldehydes or fatty acids. The invention additionally provides methods of using the above microbial organisms to produce a fatty alcohol, a fatty aldehyde or a fatty acid.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

The present invention provides an engineered cyanobacterium, comprising at least one plasmid selected from three novel pathways to produce acetate, which can convert atmospheric carbon dioxide as a raw material into acetate. The present invention also constructs the expression plasmid for three different transporters specific to acetate to be expressed in cyanobacteria, which comprises putative ABC transporter (AatA), succinate/acetate: proton symporter (SatP) and acetate/glycolate: cation symporter (ActP). Therefore, the engineered cyanobacteria of the present invention can produce 0.58 mg/L to 3.54 mg/L of acetate per hour.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

The invention provides non-naturally occurring microbial organisms containing a fatty alcohol, fatty aldehyde or fatty acid pathway, wherein the microbial organisms selectively produce a fatty alcohol, fatty aldehyde or fatty acid of a specified length. Also provided are non-naturally occurring microbial organisms having a fatty alcohol, fatty aldehyde or fatty acid pathway, wherein the microbial organisms further include an acetyl-CoA pathway. In some aspects, the microbial organisms of the invention have select gene disruptions or enzyme attenuations that increase production of fatty alcohols, fatty aldehydes or fatty acids. The invention additionally provides methods of using the above microbial organisms to produce a fatty alcohol, a fatty aldehyde or a fatty acid.

Described are composition and methods relate to reducing the redox imbalance in anaerobically growing yeast with attenuated glycerol production by re-engineering the pathway for Ac-CoA biosynthesis.

The present invention provides for a mechanism to completely replace the electron accepting function of glycerol formation with an alternative pathway to ethanol formation, thereby reducing glycerol production and increasing ethanol production. In some embodiments, the invention provides for a recombinant microorganism comprising a down-regulation in one or more native enzymes in the glycerol-production pathway. In some embodiments, the invention provides for a recombinant microorganism comprising an up-regulation in one or more enzymes in the ethanol-production pathway.

A recombinant yeast cell, fermentation compositions, and methods of use thereof are provided. The recombinant yeast cell includes at least one heterologous nucleic acid encoding one or more polypeptide having phosphoketolase activity; phosphotransacetylase activity; and/or acetylating acetaldehyde dehydrogenase activity, wherein the cell does not include a heterologous modified xylose reductase gene, and wherein the cell is capable of increased biochemical end product production in a fermentation process when compared to a parent yeast cell.