The present application relates to: a novel mutant polypeptide having isopropylmalate synthase activity; and a method for producing L-leucine by using same. L-leucine can be produced at high yield by using the mutant polypeptide according to an embodiment.

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.

Provided herein are processes and microorganisms which utilize both protein hydrolysates and carbohydrates from biomass feedstocks to produce renewable hydrocarbon compositions. Advantages of the disclosed methods may be recognized in fuel blends comprising such hydrocarbon compositions.

The present disclosure relates to a mutant strain having enhanced L-glutamic acid productivity and a method of producing L-glutamic acid using the same. The mutant strain according to one embodiment of the present disclosure has reduced production of citramalate as a by-product due to weakening or inactivation of the activity of citramalate synthase and has excellent L-glutamic acid productivity. The strain having an additional mutation in the YggB protein may produce L-glutamic acid in an improved yield due to enhancement of glutamic acid release. Thus, when the mutant strain is used, it is possible to more effectively produce L-glutamic acid.

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 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.

A novel modified polypeptide having an isopropylmalate synthase activity, a polynucleotide encoding the same, a microorganism comprising the polypeptide, and a method of producing L-leucine by culturing the microorganism.