Provided are a microorganism producing an L-amino acid or a precursor thereof, and a method of producing an L-amino acid or a precursor thereof using the microorganism.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present disclosure relates to the use of an amino acid dehydrogenase in combination with a cofactor regenerating system comprising a ketoreductase. In particular embodiments, the process can be used to prepare L-tert-leucine using a leucine dehydrogenase.

The present disclosure provides compositions and methods for rapid production of chemicals in genetically engineered microorganisms in a large scale. Also provided herein is a high-throughput metabolic engineering platform enabling the rapid optimization of microbial production strains. The platform, which bridges a gap between current in vivo and in vitro bio-production approaches, relies on dynamic minimization of the active metabolic network.

The present disclosure provides compositions and methods for rapid production of chemicals in genetically engineered microorganisms in a large scale. Also provided herein is a high-throughput metabolic engineering platform enabling the rapid optimization of microbial production strains. The platform, which bridges a gap between current in vivo and in vitro bio-production approaches, relies on dynamic minimization of the active metabolic network.

This invention relates to metabolically engineered microorganisms, such as bacterial and or fungal strains, and bioprocesses utilizing such strains. These strains enable the dynamic control of metabolic pathways, which can be used to optimize production. Dynamic control over metabolism is accomplished via a combination of methodologies including but not limited to transcriptional silencing and controlled enzyme proteolysis. These microbial strains are utilized in a multi-stage bioprocess encompassing at least two stages, the first stage in which organisms are grown and metabolism can be optimized for microbial growth and at least one other stage in which growth can be slowed or stopped, and dynamic changes can be made to metabolism to improve the production of desired product, such as a chemical or fuel.

Provided is a method for preparing β-alanine, the method comprising: preparing a β-alanine product from a reactant containing fumaric acid and aqueous ammonia in the presence of a catalyst, wherein the catalyst contains a catalyst composition containing aspartase and L-aspartic acid-α-decarboxylase, and adding fumaric acid during the reaction, wherein the total moles of the fumaric acid added is equal to the initial moles of the aqueous ammonia in the reactant minus the initial moles of the fumaric acid in the reactant. Also provided are methods for preparing a β-alanine salt (in particular calcium β-alanine, sodium β-alanine, and potassium β-alanine) and a pantothenate (in particular calcium pantothenate, sodium pantothenate, and potassium pantothenate).

Provided is a method for preparing β-alanine, the method comprising: preparing a β-alanine product from a reactant containing fumaric acid and aqueous ammonia in the presence of a catalyst, wherein the catalyst contains a catalyst composition containing aspartase and L-aspartic acid-α-decarboxylase, and adding fumaric acid during the reaction, wherein the total moles of the fumaric acid added is equal to the initial moles of the aqueous ammonia in the reactant minus the initial moles of the fumaric acid in the reactant. Also provided are methods for preparing a β-alanine salt (in particular calcium β-alanine, sodium β-alanine, and potassium β-alanine) and a pantothenate (in particular calcium pantothenate, sodium pantothenate, and potassium pantothenate).

The present disclosure relates to a genetically modified microorganism satisfying some of predetermined conditions. The predetermined conditions include: (I) succinate dehydrogenase activity or fumarate reductase activity being reduced or inactivated relative to a wild-type microorganism; (II) lactate dehydrogenase activity being reduced or inactivated relative to the wild-type microorganism; (III) the genetically modified microorganism having modified phosphoenolpyruvate carboxylase activity showing resistance to feedback inhibition by aspartic acid in wild-type phosphoenolpyruvate carboxylase activity, or exogenous phosphoenolpyruvate carboxylase activity having higher resistance to feedback inhibition by aspartic acid than that of the wild-type phosphoenolpyruvate carboxylase activity shown by the wild-type microorganism; and (IV) pyruvate:quinone oxidoreductase being reduced or inactivated relative to the wild-type microorganism.

The present disclosure relates to a genetically modified microorganism satisfying some of predetermined conditions. The predetermined conditions include: (I) succinate dehydrogenase activity or fumarate reductase activity being reduced or inactivated relative to a wild-type microorganism; (II) lactate dehydrogenase activity being reduced or inactivated relative to the wild-type microorganism; (III) the genetically modified microorganism having modified phosphoenolpyruvate carboxylase activity showing resistance to feedback inhibition by aspartic acid in wild-type phosphoenolpyruvate carboxylase activity, or exogenous phosphoenolpyruvate carboxylase activity having higher resistance to feedback inhibition by aspartic acid than that of the wild-type phosphoenolpyruvate carboxylase activity shown by the wild-type microorganism; and (IV) pyruvate:quinone oxidoreductase being reduced or inactivated relative to the wild-type microorganism.