BACULOVIRUS EXPRESSION OF BOVINE CYTOCHROME P450C17 IN SF9 CELLS AND COMPARISON WITH EXPRESSION IN YEAST, MAMMALIAN-CELLS, AND ESCHERICHIA-COLI

Expression of bovine 17 alpha-hydroxylase cytochrome P450 (P450c17) in insect Sf9 cells using baculovirus is the fourth heterologous express ion system developed for studying this enzyme. The enzyme in Sf9 cell membranes has all the expected activities and closely resembles that f rom the other systems: COS1 cells, yeast, and Escherichia, coli. One c urious feature of baculovirus expression of this hemoprotein is that t he immunodetectable P450c17 is present in an insoluble pellet when pro duced in the absence of added hemin and in a 10,000g supernatant when expressed in the presence of added hemin. When comparing the level of expression of bovine P450c17 in these different expression systems, E. coli produces the largest quantity per liter culture, while baculovir us produces the most molecules of P450c17 per cell. (C) 1994 Academic Press, Inc.