The biological production of beta-hydroxyisovalerate (βHIV) using a non-natural microorganism. The non-natural microorganism for the biologically-derived βHIV provides more beta-hydroxyisovalerate synthase activity than the wild-type parent. The non-natural microorganism can host a non-natural enzyme, such as the non-natural enzyme expressed in a yeast or bacteria, wherein the non-natural microorganism comprises an active βHIV metabolic pathway for the production of βHIV. The biological derivation of βHIV eliminates toxic by-products and impurities that result from the chemical production of βHIV, such that βHIV produced by a non-natural microorganism prior to any isolation or purification process has not been in substantial contact with any halogen-containing component.

Genetically modified LeuCD′ enzyme complexes, processes for preparing a C.sub.7-C.sub.11 2-ketoacid utilizing genetically modified LeuCD′ enzyme complexes, and microbial organisms including modified LeuCD enzyme complexes are described. The instantly-disclosed genetically modified LeuCD′ enzyme complexes, processes for preparing a C.sub.7-C.sub.11 2-ketoacid, and microbial organisms including modified LeuCD′ enzyme complexes can be particularly useful for producing C.sub.6-C.sub.10 aldehydes, alkanes, alcohols, and carboxylic acids, both in vivo and in vitro.

Genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′ enzyme complexes), microbial organisms including genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′), and processes for preparing C.sub.7-C.sub.11 2-ketoacids with genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′). The genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′ enzyme complexes), microbial organisms, and processes for preparing C.sub.7-C.sub.11 2-ketoacids can be used to produce C.sub.6-C.sub.10 aldehydes, alkanes, alcohols, and carboxylic acids, both in vivo and in vitro.

The biological production of beta-hydroxyisovalerate (βHIV) using at least one non-natural enzyme. The non-natural enzyme for the biologically-derived βHIV provides more beta-hydroxyisovalerate synthase activity than the wild-type parent. The non-natural enzyme having one or more modifications of substrate-specificity positions. The non-natural enzyme can be expressed in a microorganism, such as a yeast or bacteria, wherein the microorganism comprises an active βHIV metabolic pathway for the production of βHIV. Alternatively, the non-natural enzyme can be a βHIV synthase used to produce βHIV in a cell-free environment. The biological derivation of βHIV eliminates toxic by-products and impurities that result from the chemical production of βHIV, such that βHIV produced by a non-natural enzyme prior to any isolation or purification process has not been in substantial contact with any halogen-containing component.

The present invention relates to preparation of key drug intermediate, L-2-amino butyric acid (L-2-ABA) by a method of cell free system and biotransformation using genetically engineered strains from easily available economic substrates like citramalate or citraconate and enzymes like LeuCD, LeuB and ValDH or IlvE.

The present invention provides a method for producing 2-methyl-butyric acid by fermentation using a bacterium belonging to the order Enterobacterales which has been modified to attenuate expression of a tyrB gene encoding a protein having tyrosine aminotransferase activity. The method also allows for production of a byproduct substance of 2-methyl-butyric acid during fermentation of the Enterobacterales bacterium having 2-methyl-butyric acid-producing ability.

Genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′ enzyme complexes), microbial organisms including genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′), and processes for preparing C7-C11 2-ketoacids with genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′). The genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD′ enzyme complexes), microbial organisms, and processes for preparing C7-C11 2-ketoacids can be used to produce C6-C10 aldehydes, alkanes, alcohols, and carboxylic acids, both in vivo and in vitro.

Recombinant microbial cells are provided which have been engineered to produce fatty acid derivatives having linear chains containing an odd number of carbon atoms by the fatty acid biosynthetic pathway. Also provided are methods of making odd chain fatty acid derivatives using the recombinant microbial cells, and compositions comprising odd chain fatty acid derivatives produced by such methods.

The invention relates to a 2-isopropyl malate synthase, a genetically engineered bacterium for producing L-leucine and application thereof and belongs to the field of metabolic engineering. The genetically engineered bacterium is obtained by overexpressing an isopropyl malate synthase coding gene leuA.sup.M for relieving feedback inhibition by L-leucine, an acetohydroxy acid synthase coding gene ilvBN.sup.M for relieving feedback inhibition by L-isoleucine, a 3-isopropyl malate dehydrogenase coding gene leuB and a 3-isopropyl malate dehydratase coding gene leuCD in host cells. The genetically engineered bacterium for producing the L-leucine is free from nutritional deficiency, rapid in growth, short in fermentation period, high in yield and high in conversion rate.

Genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD enzyme complexes), microbial organisms including genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD), and processes for preparing C.sub.7-C.sub.11 2-ketoacids with genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD). The genetically modified isopropylmalate isomerase enzyme complexes (e.g., LeuCD enzyme complexes), microbial organisms, and processes for preparing C.sub.7-C.sub.11 2-ketoacids can be used to produce C.sub.6-C.sub.10 aldehydes, alkanes, alcohols, and carboxylic acids, both in vivo and in vitro.