An unusual yet strongly conserved flavoprotein reductase in bacteria and mammals

Trends Biochem Sci. 1991 Apr;16(4):154-8. doi: 10.1016/0968-0004(91)90059-5.


The recent determination of the amino acid sequences of the Bacillus megaterium cytochrome P-450 and the flavoprotein component of Salmonella typhimurium NADPH-sulfite reductase revealed that these enzymes contain a flavoprotein moiety remarkably similar to mammalian NADPH-cytochrome P-450 reductase. The presence of this oxidoreductase in these very different enzymes suggests that this flavoprotein arose early in evolution and was utilized as an enzymological building block. The multi-domain structure of the reductase further suggests that it arose through a fusion of genes encoding simple flavin electron-transport proteins.

Publication types

  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bacillus megaterium / enzymology
  • Bacillus megaterium / genetics*
  • Base Sequence
  • Flavoproteins / genetics*
  • Molecular Sequence Data
  • NADPH-Ferrihemoprotein Reductase / genetics*
  • Oxidoreductases Acting on Sulfur Group Donors / genetics*
  • Salmonella typhimurium / enzymology
  • Salmonella typhimurium / genetics*
  • Sulfite Reductase (NADPH)


  • Flavoproteins
  • NADPH-Ferrihemoprotein Reductase
  • Oxidoreductases Acting on Sulfur Group Donors
  • Sulfite Reductase (NADPH)