The invention relates to engineering of acetyl-CoA metabolism in yeast and in particular to production of acetyl-CoA in a non-ethanol producing yeast lacking endogenous gene(s) encoding pyruvate decarboxylase and comprising a heterologous pathway for synthesis of cytosolic acetyl-CoA.

The invention is directed to a process for producing one or more fermentation product in a multi-stage process including an inoculation reactor and at least one bioreactor. The inoculation reactor is fed a C1-containing gaseous substrate containing a reduced amount of hydrogen. The hydrogen is reduced to increase the proportion of CO in the C1-containing gaseous substrate being provided to the inoculation reactor. The inoculation reactor ferments the CO-rich C1-containing gaseous substrate and produces an inoculum, which is fed to at least one bioreactor. The bioreactor receives the C1-containing gaseous substrate, which may or may not contain reduced amounts of hydrogen, to produce one or more fermentation product. By providing a CO-rich C1-containing gaseous substrate to the inoculation reactor, both the inoculation reactor and the subsequent bioreactor(s), are able to have increased stability and product selectivity.

The invention is directed to a process for producing one or more fermentation product in a multi-stage process including an inoculation reactor and at least one bioreactor. The inoculation reactor is fed a C1-containing gaseous substrate containing a reduced amount of hydrogen. The hydrogen is reduced to increase the proportion of CO in the C1-containing gaseous substrate being provided to the inoculation reactor. The inoculation reactor ferments the CO-rich C1-containing gaseous substrate and produces an inoculum, which is fed to at least one bioreactor. The bioreactor receives the C1-containing gaseous substrate, which may or may not contain reduced amounts of hydrogen, to produce one or more fermentation product. By providing a CO-rich C1-containing gaseous substrate to the inoculation reactor, both the inoculation reactor and the subsequent bioreactor(s), are able to have increased stability and product selectivity.

A method which enables olefin compound production with a high productivity and an enzyme used in the method, a mutation involving amino acid substitution has been introduced into various sites of diphosphomevalonate decarboxylase (MVD), thus preparing a large number of MVD variants. Next, the result of evaluating the variants for the catalytic activity related to the production of olefin compounds such as isoprene has revealed that MVD whose threonine at position 209 is substituted with a different amino acid has the catalytic activity, and that MVD whose arginine at position 74 is further substituted with a different amino acid in addition to position 209 has the catalytic activity at higher levels.

Described herein are methods of producing (+)-manool, the methods including: contacting geranylgeranyl diphosphate with a copalyl diphosphate (CPP) synthase to form a (9S, 10S)-copalyl diphosphate and contacting the CPP with a sclareol synthase enzyme to form (+)-manool and derivatives thereof. Also described herein are nucleic acids encoding CPP synthases and sclareol synthases for use in the methods. Further described herein are expression vectors and non-human host organisms and cells including nucleic acids encoding a CPP synthase and a sclareol synthase as described herein.

Provided is a system for hydrolyzing a cellulosic feedstock slurry. The system comprises one or more unmixed reactors for receiving and partially hydrolyzing the cellulosic feedstock slurry so as to produce a mixture of partially hydrolyzed slurry. The unmixed reactors may be plug flow reactors. One or more mixed reactors are downstream of the unmixed reactors for continuing the hydrolysis of the mixture of the partially hydrolyzed slurry. The one or more unmixed and mixed reactors may be connected in series, parallel or a combination thereof.

Provided is a mutant of the wild type phosphatidylcholine-specific phospholipase C of Bacillus cereus. The mutations involved comprise the amino acid residue at position 63 being mutated from asparagine to aspartic acid, the amino acid residue at position 131 being mutated from asparagine to serine, and the amino acid residue at position 134 being mutated from asparagine to aspartic acid, and may comprise the amino acid residue at position 56 being mutated from tyrosine to alanine, lysine, asparagine, glutamine, histidine or tryptophan, and further, may also comprise the amino acid residue at position 106 being mutated from methionine to valine. Also provided are a polynucleotide molecule encoding the mutant, a nucleic acid construct and a host cell comprising the polynucleotide molecule, a composition comprising the mutant, and the use of the mutant, the polynucleotide molecule, the nucleic acid construct and the host cell.

Provided is a mutant of the wild type phosphatidylcholine-specific phospholipase C of Bacillus cereus. The mutations involved comprise the amino acid residue at position 63 being mutated from asparagine to aspartic acid, the amino acid residue at position 131 being mutated from asparagine to serine, and the amino acid residue at position 134 being mutated from asparagine to aspartic acid, and may comprise the amino acid residue at position 56 being mutated from tyrosine to alanine, lysine, asparagine, glutamine, histidine or tryptophan, and further, may also comprise the amino acid residue at position 106 being mutated from methionine to valine. Also provided are a polynucleotide molecule encoding the mutant, a nucleic acid construct and a host cell comprising the polynucleotide molecule, a composition comprising the mutant, and the use of the mutant, the polynucleotide molecule, the nucleic acid construct and the host cell.

The invention provides genetically engineered Wood-Ljungdahl microorganisms comprising one or more disrupted genes to strategically divert carbon flux away from nonessential or undesirable products and towards products of interest. The expression strategies of the invention enable the production of useful fuels and chemicals from gaseous substrates, such as carbon monoxide, carbon dioxide, and/or hydrogen.

The invention provides genetically engineered Wood-Ljungdahl microorganisms comprising one or more disrupted genes to strategically divert carbon flux away from nonessential or undesirable products and towards products of interest. The expression strategies of the invention enable the production of useful fuels and chemicals from gaseous substrates, such as carbon monoxide, carbon dioxide, and/or hydrogen.