Methods of microbial screening for identifying alcohol acyltransferases for ester biosynthesis and submodules for ester pathways to produce butyryl-coenzyme A derived esters are disclosed. The method includes the introduction preselected plasmids into a respective host strain to form engineered microbes, in situ fermentation thereof followed by a colorimetric assay for quantification of production of the target ester. In situ fermentation includes inoculating each well of a microplate that have a culture media for producing target esters with one of the engineered microbes, adding an overlay of a solvent to each, and incubating the same. The colorimetric assay includes transfer of a quantity of the overlay from each well to respective clean wells of a new microplate, treatment of each well to form an iron-hydroxamic acid complex aqueous phase, centrifugation of the microplate, and measurement of the absorbance at 520 nm and comparison to a standard curve for the target ester.

The use of microorganisms to make alpha-functionalized chemicals and fuels, (e.g. alpha-functionalized carboxylic acids, alcohols, hydrocarbons, amines, and their beta-, and omega-functionalized derivatives), by utilizing an iterative carbon chain elongation pathway that uses functionalized extender units. The core enzymes in the pathway include thiolase, dehydrogenase, dehydratase and reductase. Native or engineered thiolases catalyze the condensation of either unsubstituted or functionalized acyl-CoA primers with an alpha-functionalized acetyl-CoA as the extender unit to generate alpha-functionalized β-keto acyl-CoA. Dehydrogenase converts alpha-functionalized β-keto acyl-CoA to alpha-functionalized β-hydroxy acyl-CoA. Dehydratase converts alpha-functionalized β-hydroxy acyl-CoA to alpha-functionalized enoyl-CoA. Reductase converts alpha-functionalized enoyl-CoA to alpha-functionalized acyl-CoA. The platform can be operated in an iterative manner (i.e. multiple turns) by using the resulting alpha-functionalized acyl-CoA as primer and the aforementioned alpha-functionalized extender unit in subsequent turns of the cycle. Termination pathways acting on any of the four alpha-functionalized CoA thioester intermediates terminate the platform and generate various alpha-functionalized carboxylic acids, alcohols and amines with different β-reduction degree.

The present disclosure provides recombinant microorganisms and methods for the anaerobic production of 2,4-furandicarboxylic acid from one or more carbon sources. The microorganisms and methods provide redox-balanced and ATP positive pathways for co-producing 2,4-furandicarboxylic acid with ethanol and for co-producing 2,4-furandicarboxylic acid with ethanol and 1-propanol. The method provides recombinant microorganisms that express endogenous and/or exogenous nucleic acid molecules encoding polypeptides that catalyze the conversion of a carbon source into 2,4-furandicarboxylic acid and that coupled the 2,4-furandicarboxylic acid pathway with an additional metabolic pathway.

The present disclosure belongs to the field of bioengineering, and relates to breeding of industrial microorganisms, in particular to a genetically engineered strain of Saccharomyces cerevisiae, method for constructing the same, and its use for brewing, the genetically engineered strain of Saccharomyces cerevisiae heterogeneously overexpresses an acetaldehyde dehydrogenase gene ALD6, an acetyl-CoA synthase gene ACS1 and an alcohol acyltransferase gene AeAT9. The Saccharomyces cerevisiae strain with high yield of ethyl acetate and low yield of higher alcohols provided by the present disclosure not only maintains excellent ethanol fermentation characteristics, but also reducing the production of higher alcohols which adversely affect the comfort after drinking, which is of great significance for a well-maintained and strengthened flavor characteristics of Chinese Baijiu, an improved and stabilized quality thereof, and even a reform in the fermentation process thereof.

A combination of an electrochemical device for delivering reducing equivalents to a cell, and engineered metabolic pathways within the cell capable of utilizing the electrochemically provided reducing equivalents is disclosed. Such a combination allows the production of commodity chemicals by fermentation to proceed with increased carbon efficiency.

Metabolites produced by a microorganism using oxaloacetate, pyruvate and/or acetyl-CoA as substrate or co-substrate upstream in the biosynthesis pathway, and more particularly using oxaloacetate. There is indeed a need in the art for transformed, in particular recombinant, microorganisms having at least an increased ability to produce oxaloacetate, pyruvate and/or acetyl-CoA, and in particular oxaloacetate, thus allowing an increased capacity to produce metabolites produced using oxaloacetate, pyruvate and/or acetyl-CoA as substrate or co-substrate upstream in the biosynthesis pathway, and in particular amino acids and their derivatives thereof, fatty acids, derivatives from the mevalonate pathway (in particular farnesyl, squalene, lanosterol, cholesterol and derivatives, and dolichols), flavonoides and/or polyketides. The solution proposed is the use of a genetically modified yeast comprising many modifications as described in the present text.

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.

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 present invention relates to a transformed strain having ethanol production potential, constructed by introducing a foreign gene for ethanol production into a non-ethanol producing acetogen Eubacterium limosum and a method for producing ethanol, using the strain. According to the present invention, Eubacterium limosum which is a conventional acetogen lacking ethanol production potential is used to produce ethanol, which is a high value-added product, as a single product from carbon monoxide contained in waste gas.

The invention relates to a process for producing a fermentation product that comprises fermentation of a carbon source in a reactor with a cell, capable of converting sugar, glycerol and acetic acid, wherein the carbon source comprises sugar and acetic acid, comprising the following steps: a) Inoculating a optionally diluted carbon source with the cell; b) optionally fermenting the reactor in batch mode; c) adding carbon source comprising glycerol and optionally sugar gradually to the reactor; d) after sufficient fermentation time, isolation of fermentation product from the reactor, e) optionally keeping the remaining fraction after isolation of step d) as spent broth; and f) optionally using the spent broth in step a) to dilute the carbon source.