'Keto acids', also known as ketone bodies, are water-soluble compounds - acetoacetic acid, beta-hydroxybutyric acid, and acetone - that are produced during fat metabolism when liver glycogen stores are depleted, providing an alternative energy source for the brain and other organs in states of carbohydrate restriction or intense physical exertion.

Oxidoreductases that are specific for KETONES.

Derivatives of caproic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated six carbon aliphatic structure.

A ketone oxidoreductase that catalyzes the overall conversion of alpha-keto acids to ACYL-CoA and CO2. The enzyme requires THIAMINE DIPHOSPHATE as a cofactor. Defects in genes that code for subunits of the enzyme are a cause of MAPLE SYRUP URINE DISEASE. The enzyme was formerly classified as EC 1.2.4.3.

A subclass of enzymes of the transferase class that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Most of these enzymes are pyridoxyl phosphate proteins. (Dorland, 28th ed) EC 2.6.1.

A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)

Amino acids which have a branched carbon chain.

3-(p-Fluorophenyl)-alanine.

A group of compounds that are derivatives of phenylpyruvic acid which has the general formula C6H5CH2COCOOH, and is a metabolite of phenylalanine. (From Dorland, 28th ed)

An autosomal recessive inherited disorder with multiple forms of phenotypic expression, caused by a defect in the oxidative decarboxylation of branched-chain amino acids (AMINO ACIDS, BRANCHED-CHAIN). These metabolites accumulate in body fluids and render a "maple syrup" odor. The disease is divided into classic, intermediate, intermittent, and thiamine responsive subtypes. The classic form presents in the first week of life with ketoacidosis, hypoglycemia, emesis, neonatal seizures, and hypertonia. The intermediate and intermittent forms present in childhood or later with acute episodes of ataxia and vomiting. (From Adams et al., Principles of Neurology, 6th ed, p936)

An essential branched-chain aliphatic amino acid found in many proteins. It is an isomer of LEUCINE. It is important in hemoglobin synthesis and regulation of blood sugar and energy levels.

An essential branched-chain amino acid important for hemoglobin formation.

An unnatural amino acid that is used experimentally to study protein structure and function. It is structurally similar to METHIONINE, however it does not contain SULFUR.

The Ketoglutarate Dehydrogenase Complex is a multi-enzyme complex involved in the citric acid cycle, catalyzing the oxidative decarboxylation of alpha-ketoglutarate to succinyl-CoA and CO2, thereby connecting the catabolism of amino acids, carbohydrates, and fats to the generation of energy in the form of ATP.

Amino acids that are not synthesized by the human body in amounts sufficient to carry out physiological functions. They are obtained from dietary foodstuffs.

Pyruvates, in the context of medical and biochemistry definitions, are molecules that result from the final step of glycolysis, containing a carboxylic acid group and an aldehyde group, playing a crucial role in cellular metabolism, including being converted into Acetyl-CoA to enter the Krebs cycle or lactate under anaerobic conditions.

Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.

A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.

An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.

Valerates are salts or esters formed from the reaction between valerianic acid and a base, characterized by their tranquilizing and sedative properties, often used in pharmaceuticals and dietary supplements for promoting sleep and reducing anxiety.

An intermediate compound in the metabolism of carbohydrates, proteins, and fats. In thiamine deficiency, its oxidation is retarded and it accumulates in the tissues, especially in nervous structures. (From Stedman, 26th ed)

Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.

Coenzyme A is an essential coenzyme that plays a crucial role in various metabolic processes, particularly in the transfer and activation of acetyl groups in important biochemical reactions such as fatty acid synthesis and oxidation, and the citric acid cycle.

The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)

Proteins obtained from foods. They are the main source of the ESSENTIAL AMINO ACIDS.

A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).

A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.

Derivatives of BUTYRIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxypropane structure.

The rate dynamics in chemical or physical systems.

A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of RENAL INSUFFICIENCY. Most uremic toxins are end products of protein or nitrogen CATABOLISM, such as UREA or CREATININE. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms.

A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)