Alexander L. Dounce

[137] Liver catalase

Publisher Summary This chapter discusses the determination of liver catalase. Next to urease, beef liver catalase is possibly the easiest enzyme to obtain in crystalline condition. The reasons for this are the unusual stability of this enzyme, its insolubility in water at its isoelectric point, and its relatively high concentration in beef liver. Since the preparation of crystalline catalase from beef liver by Sumner and Dounce crystalline catalases have been obtained from a number of other sources. These are: lamb liver, horse liver, beef erythrocytes, horse kidney and human liver, guinea pig liver, Micrococcus lysodeikticus, and pig liver. Catalase can be purified by being adsorbed on tricalcium phosphate in a Tswett column at pH 5.7 and later by eluting with phosphate buffer of pH 8.0. However, since most preparations of tricalcium phosphate are rather impermeable to water, it is probably better to adsorb on Celite. The chapter also describes a method for the determination of catalase activity which in all probability is the best yet devised for solutions of pure or partially purified catalase.