TY - JOUR T1 - Purification of Liver Microsomal Cytochrome P-448 from 3-Methylcholanthrene-Treated Rabbits JF - Molecular Pharmacology JO - Mol Pharmacol SP - 874 LP - 878 VL - 11 IS - 6 AU - JOSEPH C. KAWALEK AU - WAYNE LEVIN AU - DENE RYAN AU - PAUL E. THOMAS AU - ANTHONY Y. H. LU Y1 - 1975/11/01 UR - http://molpharm.aspetjournals.org/content/11/6/874.abstract N2 - Rabbit liver microsomal cytochrome P-448 has been highly purified to a specific content of greater than 20 nmoles/mg of protein. Sodium dodecyl sulfate-gel electrophoresis showed the presence of a major polypeptide band with a molecular weight of 5l,000 and a faint minor band at 60,000. Purified rabbit cytochrome P-448 differs from cytochrome P-448 purified from rats with respect to its molecular size, its poor reactivity with antibody produced against rat cytochrome P-448, and its relative inactivity for the hydroxylation of several substrates. These results indicate that rabbit cytochrome P-448 and rat cytochrome P-448 are different proteins. ACKNOWLEDGMENTS We thank Dr. C. Y. Lai and Mr. D. Chang of the Roche Institute of Molecular Biology, Nutley, N. J., for conducting the amino acid analysis. We also thank Mrs. Margaret Althoff for her assistance in the preparation of this manuscript. ER -