Purification of squalene epoxidase from rat liver microsomes

Abstract

Squalene epoxidase was purified from rat liver microsomes by DEAE-cellulose, alumina C ν gel, hydroxylapatite, CM-Sephadex C-50 and Cibacron Blue Sepharose 4B in the presence of Triton X-100. The specific activity was increased 50 fold with a yield of about 10%. On SDS-polyacrylamide gel electrophoresis, the preparation gave one major band and one minor band with apparent molecular weights of 47,000 and 27,000 daltons, respectively. The protein of 47,000 was the most probable candidate for squalene epoxidase. Squalene epoxidase activity could be reconstituted in the squalene epoxidase preparation with the addition of NADPH-cytochrome P-450 reductase, FAD, and Triton X-100.