A study of the catalase monomer produced by lyophilization

• Published in: Biochimica et biophysica acta, Protein structure and molecular enzymology Vol. 925; no. 3; pp. 282 - 289
• Main Authors: Sichak, S P, Dounce, AL
• Format: Journal Article
• Language: English
• Published: 01.01.1987
• Subjects: catalase; freeze drying; liver
• ISSN: 0167-4838

Lyophilization of Dounce and Mourtzikos beef liver catalase under specified conditions produced conformationally altered but not completely denatured catalase monomer which retained both significant catalatic activity and peroxidatic activity towards ethanol. The same lyophilization procedure used with Sigma Co. catalase produced a mixture of conformationally altered catalase monomer and conformationally altered tetramer which showed still higher catalatic and peroxidatic activities; this was attributed to the presence of the altered tetramer. The conformationally altered catalase tetramer, which shows more enzymatic activity than the monomer, evidently retains a higher proportion of its native conformation than the monomer, but still appears to be fully reducible with dithionite. A possible explanation for the observed differences in lyophilization products depending on the starting material is presented.