Temperature effect on the functional expression of human cytochromes P450 2A6 and 2E1 in Escherichia coli

Abstract

Human cytochromes P450 (CYP) 2A6 and 2E1 are of great interest because of their important roles in the oxidation of numerous drugs and carcinogens. Bacterial expression systems, especially Escherichia coli cells, have been widely used for the production of various CYP enzymes in order to obtain high yield of proteins. The expression methods usually employ longer culture time (30-72 h) at lower temperature (usually under 30°C). Expression levels of CYPs 2A6 and 2E1 at 37°C were compared to those at 28°C, which is a usual temperature used in most bacterial expression systems for human CYP expression. Within 18 h the expression levels of CYPs 2A6 and 2E1 reached up to 360 and 560 nmol per liter culture at 37°C, respectively, which are compatible with those of 36 h culture at 28°C. The activities of CYPs expressed at 37°C were also comparable to those expressed at 28°C. The present overexpression system can be useful for rapid production of large amounts of active human CYPs 2A6 and 2E1 in E. coli.