Biomaterial Database

An acyl-coenzyme A chain length dependent assay for 3-oxoacyl-coenzyme A thiolases employing acetyldithio-coenzyme A. 1991

L V Wrensford, and C Coppola, and V E Anderson

Department of Chemistry, Brown University, Providence, Rhode Island 02912.

An assay for 3-oxoacyl-coenzyme A (3-oxoacyl-CoA) thiolases is described. The reaction utilizes acetyldithio-CoA as the nucleophile and variable chain length saturated acyl-CoA's as the electrophiles. The properties of the 3-oxoacyl-CoA dithioester product, notably a pKa of 6.6 +/- 0.1 and an extinction coefficient of 21,600 cm-1 M-1 for the enethiolate at 357 nm, make it possible to spectrophotometrically follow the reaction in the thermodynamically unfavorable carbon-carbon bond-forming direction. These properties eliminate both the background decomposition and the dependence on Mg2+, chain length, and pH that complicate assays with 3-oxoacyl-CoA substrates. Purified thiolase I from pig liver was 140-fold more active with butyryl-CoA as the electrophile than with acetyl-CoA and 38-fold more reactive with hexanoyl-CoA than with myristoyl-CoA. Beef liver homogenate showed a much greater relative activity with myristoyl-CoA as the electrophile than either purified pig heart thiolase I or pig heart homogenate. The analysis of the separation of thiolases by anion-exchange chromatography is simplified and further suggests the existence of isozymes with varying chain length specificities.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D002852	Chromatography, Ion Exchange	Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.	Chromatography, Ion-Exchange,Ion-Exchange Chromatography,Chromatographies, Ion Exchange,Chromatographies, Ion-Exchange,Ion Exchange Chromatographies,Ion Exchange Chromatography,Ion-Exchange Chromatographies
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000102	Acetyl-CoA C-Acyltransferase	Enzyme that catalyzes the final step of fatty acid oxidation in which ACETYL COA is released and the CoA ester of a fatty acid two carbons shorter is formed.	3-Ketoacyl CoA Thiolase,3-Ketothiolase,Acetyl CoA Acyltransferase,Acetyl Coenzyme A Acyltransferase,beta-Ketothiolase,2-Methylacetoacetyl CoA Thiolase,3-Oxoacyl CoA Thiolase,3-Oxoacyl-Coenzyme A Thiolase,beta-Ketoacyl Thiolase,Acetyl CoA C Acyltransferase,Acyltransferase, Acetyl CoA,C-Acyltransferase, Acetyl-CoA,CoA Acyltransferase, Acetyl,CoA Thiolase, 2-Methylacetoacetyl,CoA Thiolase, 3-Ketoacyl,CoA Thiolase, 3-Oxoacyl,Thiolase, 2-Methylacetoacetyl CoA,Thiolase, 3-Ketoacyl CoA,Thiolase, 3-Oxoacyl CoA,Thiolase, 3-Oxoacyl-Coenzyme A,Thiolase, beta-Ketoacyl,beta Ketoacyl Thiolase,beta Ketothiolase
D000214	Acyl Coenzyme A	S-Acyl coenzyme A. Fatty acid coenzyme A derivatives that are involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.	Acyl CoA,Fatty Acyl CoA,Long-Chain Acyl CoA,Acyl CoA, Fatty,Acyl CoA, Long-Chain,CoA, Acyl,CoA, Fatty Acyl,CoA, Long-Chain Acyl,Coenzyme A, Acyl,Long Chain Acyl CoA
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog