Purification of beta-hydroxy-beta-methylglutaryl-coenzyme A reductase from yeast

Beta-Hydroxy-beta-methylglutaryl-coenzyme A reductase of yeast has been solubilized by two different methods and then purified approximately 5000-fold. The purified enzyme shows a single precipitin band on immunodiffusion, and it moves as a single band of protein and enzyme activity on gel filtration and diethylaminoethylcellulose column chromatography. It also shows one major band on polyacrylamide gel electrophoresis. The specific activity of the pure enzyme is 18 000 to 22 000 nmol of reduced nicotinamide adenine dinucleotide phosphate oxidized per min per mg of protein. The molecular weights of the enzyme, estimated by gel filtration, and the subunits, determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis, are 2.6 X 10(5) and 6.0 X 10(4), respectively.