Genetically modified microorganisms that have the ability to convert carbon substrates into chemical products such as isobutanol are disclosed. For example, genetically modified methanotrophs that are capable of generating isobutanol at high titers from a methane source are disclosed. Methods of making these genetically modified microorganisms and methods of using them are also disclosed.

Modified Saccharomyces cerevisiae yeast that produce terminal alkenes are described. The modification of the Saccharomyces cerevisiae yeast includes insertion of at least one heterologous fatty acid decarboxylase gene, deletion of FAA1 and FAA4, overexpression of HEM3, and triple-deletion of CTT1, CTA1 and CCP1. Methods of producing terminal alkenes by culturing and fermenting the modified Saccharomyces cerevisiae yeast and optionally harvesting the terminal alkenes are also described. Mixtures of terminal alkenes produced by the modified Saccharomyces cerevisiae yeast, and methods of metabolically engineering a yeast for optimizing overexpression of one or more alkenes are also described.

The invention relates to a modified microorganism for the production of PDO from a carbon substrate wherein the microorganism includes a three-step metabolic pathway including a first step of conversion of 2,4-dihydroxybutyrate (DHB) to obtain 2-oxo-4-hydroxybutyrate (OHB) by an enzyme having 2,4-DHB dehydrogenase activity, a second step of decarboxylation of the OHB to obtain 3-hydroxypropionaldehyde by an enzyme having 2-oxo-4-hydroxybutyrate decarboxylase activity, and a third step of reduction of the obtained 3-hydroxypropionaldehyde to obtain PDO with an enzyme having 3-hydroxypropionaldehyde reductase activity and the genes enabling the microorganism for the synthesis of DHB.

An engineered microorganism, which comprises one or more of a gene encoding an aromatic amino acid transaminase, a gene encoding phenylalanine dehydrogenase, a gene encoding phenylpyruvate decarboxylase, a gene encoding an aldehyde reductase, a gene encoding glutamate dehydrogenase, and a gene encoding a phenylalanine transport protein, or a functional equivalent thereof. The present invention also relates to a composition comprising the engineered microorganism; a method for using the engineered microorganism or the composition to alleviate and/or treat diseases and/or conditions associated with hyperphenylalaninemia; and use of the engineered microorganism or the composition in the preparation of medicaments or health products for treating diseases and/or conditions associated with hyperphenylalaninemia.

Methods for the fermentative production of four carbon alcohols is provided. Specifically, butanol, preferably isobutanol is produced by the fermentative growth of a recombinant bacterium expressing an isobutanol biosynthetic pathway.

Genetically modified microorganisms that have the ability to convert carbon substrates into chemical products such as isobutanol are disclosed. For example, genetically modified methanotrophs that are capable of generating isobutanol at high titers from a methane source are disclosed. Methods of making these genetically modified microorganisms and methods of using them are also disclosed.

Multi-carbon compounds such as ethanol, n-butanol, sec-butanol, isobutanol, tert-butanol, fatty (or aliphatic long chain) alcohols, fatty acid methyl esters, 2,3-butanediol and the like, are important industrial commodity chemicals with a variety of applications. The present invention provides metabolically engineered host microorganisms which metabolize methane (CH.sub.4) as their sole carbon source to produce multi-carbon compounds for use in fuels (e.g., bio-fuel, bio-diesel) and bio-based chemicals. Furthermore, use of the metabolically engineered host microorganisms of the invention (which utilize methane as the sole carbon source) mitigate current industry practices and methods of producing multi-carbon compounds from petroleum or petroleum-derived feedstocks, and ameliorate much of the ongoing depletion of arable food source farmland currently being diverted to grow bio-fuel feedstocks, and as such, improve the environmental footprint of future bio-fuel, bio-diesel and bio-based chemical compositions.