Biomaterial Database

Purification and characterization of the branched chain alpha-ketoacid dehydrogenase complex from Saccharomyces cerevisiae. 1993

D A Sinclair, and I W Dawes, and J R Dickinson

School of Biochemistry and Molecular Genetics, University of New South Wales, Kensington, Australia.

Branched chain alpha-ketoacid dehydrogenase complex was purified from Saccharomyces cerevisiae by polyethylene glycol fractionation and chromatography on Sephacryl S-200, DEAE-cellulose and Sepharose CL-2B. Electrophoresis on sodium dodecyl sulfate-polyacrylamide gels indicated the enzyme contained subunits of M(r) = 57,000, 52,000, 47,000 and 38,000. The specific activity of the purified enzyme was 0.82 mumol NADH/min/mg protein at 30 degrees C with 16 mM alpha-ketoisovalerate as substrate. The apparent Km values for alpha-ketoisovalerate, alpha-ketoisocaproate and alpha-keto-beta-methylvalerate were 21, 22, and 20 mM, respectively. The preparation was also able to oxidize the intermediates of threonine and methionine metabolism, alpha-keto-gamma-methiolbutyrate and alpha-ketobutyrate, with Km values of 13 and 8 mM, respectively.

UI	MeSH Term	Description	Entries
D007651	Keto Acids	Carboxylic acids that contain a KETONE group.	Oxo Acids,Oxoacids,Acids, Keto,Acids, Oxo
D007658	Ketone Oxidoreductases	Oxidoreductases that are specific for KETONES.	Oxidoreductases, Ketone
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009097	Multienzyme Complexes	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.	Complexes, Multienzyme
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
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013056	Spectrophotometry, Ultraviolet	Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Ultraviolet Spectrophotometry
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