Enhanced in vivo monooxygenase activities of mammalian P450s in engineered yeast cells producing high levels of NADPH-P450 reductase and human cytochrome b5

Gene. 1993 Mar 15;125(1):49-55. doi: 10.1016/0378-1119(93)90744-n.


We have engineered yeast genomic DNA to construct a set of strains producing various relative amounts of yeast NADPH-P450 reductase (Yred) and human cytochrome b5 (Hb5). Expression of cDNAs encoding human P450 1A1, 1A2, 3A4, 19A and mouse P450 1A1 in the different oxido-reduction backgrounds thus constituted were achieved after strain transformation by plasmid-based P450-encoding expression cassettes. The results indicate that the level of Yred strongly affects all activities tested. In contrast, the amount of Hb5 affects activities in a manner that is dependent both on the P450 isoform considered and the Yred level. In a strain containing optimized amounts of Hb5 and Yred, human P450 3A4-specific testosterone-6 beta-hydroxylase activity can be enhanced as much as 73-fold in comparison with the activity observed in a wild-type strain. Bioconversion of sterols or xenobiotics was easily achieved in vivo using this new co-expression system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biotransformation
  • Cytochrome P-450 Enzyme System / genetics*
  • Cytochrome P-450 Enzyme System / metabolism*
  • Cytochromes b5 / genetics*
  • Cytochromes b5 / physiology*
  • Gene Expression Regulation, Enzymologic / genetics*
  • Gene Expression Regulation, Fungal
  • Genetic Engineering / methods
  • Humans
  • Mice
  • NADPH-Ferrihemoprotein Reductase / genetics*
  • NADPH-Ferrihemoprotein Reductase / physiology*
  • Promoter Regions, Genetic
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics


  • Cytochromes b5
  • Cytochrome P-450 Enzyme System
  • NADPH-Ferrihemoprotein Reductase