Biomaterial Database

Measurement of choline acetyltransferase with [14C]acetate by a cycling procedure. 1987

J J O'Neill, and K A Hruschak

A multiple enzyme and multisubstrate cycling system is described for the radiometric determination of cholineacetyltransferase (ChAT) activity in crude tissue homogenates. The methods employs [14C]acetate coupled with the enzymes acetate kinase (AK) and phosphotransacetylase (PTA) for the generation of [14C]acetyl CoA. By recycling it was possible to avoid product inhibition of ChAT by CoA, ATP was maintained constant by rephosphorylation of ADP. Kinetics of the individual enzyme reactions were studied and the parameters obtained were used to select appropriate conditions to maintain linearity of varying amounts ChAT activity over a sixty minute time course. The sensitivity of the method is limited only by the specific activity of commercially available isotope labeled acetate.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010709	Phosphate Acetyltransferase	An enzyme that catalyzes the synthesis of acetylphosphate from acetyl-CoA and inorganic phosphate. Acetylphosphate serves as a high-energy phosphate compound. EC 2.3.1.8.	Phosphoacylase,Phosphotransacetylase,Phosphotransacylase,Phosphotransbutyrylase,Acetyltransferase, Phosphate
D011770	Pyruvate Kinase	ATP:pyruvate 2-O-phosphotransferase. A phosphotransferase that catalyzes reversibly the phosphorylation of pyruvate to phosphoenolpyruvate in the presence of ATP. It has four isozymes (L, R, M1, and M2). Deficiency of the enzyme results in hemolytic anemia. EC 2.7.1.40.	L-Type Pyruvate Kinase,M-Type Pyruvate Kinase,M1-Type Pyruvate Kinase,M2-Type Pyruvate Kinase,Pyruvate Kinase L,R-Type Pyruvate Kinase,L Type Pyruvate Kinase,M Type Pyruvate Kinase,M1 Type Pyruvate Kinase,M2 Type Pyruvate Kinase,Pyruvate Kinase, L-Type,Pyruvate Kinase, M-Type,Pyruvate Kinase, M1-Type,Pyruvate Kinase, M2-Type,Pyruvate Kinase, R-Type,R Type Pyruvate Kinase
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002250	Carbon Radioisotopes	Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.	Radioisotopes, Carbon
D002795	Choline O-Acetyltransferase	An enzyme that catalyzes the formation of acetylcholine from acetyl-CoA and choline. EC 2.3.1.6.	Choline Acetylase,Choline Acetyltransferase,Acetylase, Choline,Acetyltransferase, Choline,Choline O Acetyltransferase,O-Acetyltransferase, Choline
D000084	Acetate Kinase	An enzyme that catalyzes reversibly the phosphorylation of acetate in the presence of a divalent cation and ATP with the formation of acetylphosphate and ADP. It is important in the glycolysis process. EC 2.7.2.1.	Acetokinase,Kinase, Acetate
D000085	Acetates	Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.	Acetate,Acetic Acid Esters,Acetic Acids,Acids, Acetic,Esters, Acetic Acid
D000105	Acetyl Coenzyme A	Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent.	Acetyl CoA,Acetyl-CoA,CoA, Acetyl,Coenzyme A, Acetyl