Function and Biology

Crystal structure of CYP3A4 ligated to oxazole-substituted desoxyritonavir

Source organism: Homo sapiens
Biochemical function: heme binding
Biological process: oxidation-reduction process
Cellular component: integral component of membrane

EC 1.14.13.97: Taurochenodeoxycholate 6-alpha-hydroxylase

Reaction catalysed:
(1) Taurochenodeoxycholate + NADPH + O(2) = taurohyocholate + NADP(+) + H(2)O. (2) Lithocholate + NADPH + O(2) = hyodeoxycholate + NADP(+) + H(2)O.
Comments:
  • Requires cytochrome b5 for maximal activity.
  • Acts on taurochenodeoxycholate, taurodeoxycholate and less readily on lithocholate and chenodeoxycholate.
  • In adult pig (Sus scrofa), hyocholic acid replaces cholic acid as a primary bile acid.
Systematic name:
Taurochenodeoxycholate,NADPH:oxygen oxidoreductase (6-alpha-hydroxylating)
Alternative Name(s):
  • CYP3A4
  • CYP4A21
  • Taurochenodeoxycholate 6-alpha-monooxygenase

EC 1.14.14.1: Unspecific monooxygenase

Reaction catalysed:
RH + [reduced NADPH--hemoprotein reductase] + O(2) = ROH + [oxidized NADPH--hemoprotein reductase] + H(2)O.
Comments:
  • Acts on a wide range of substrates including many xenobiotics, steroids, fatty acids, vitamins and prostaglandins; reactions catalyzed include hydroxylation, epoxidation, N-oxidation, sulfooxidation, N-, S- and O-dealkylations, desulfation, deamination, and reduction of azo, nitro and N-oxide groups.
  • Together with EC 1.6.2.4, it forms a system in which two reducing equivalents are supplied by NADPH.
  • Some of the reactions attributed to EC 1.14.15.3 belong here.
  • Formerly EC 1.14.1.1, EC 1.14.14.2, EC 1.14.99.8 and EC 1.99.1.1.
Systematic name:
Substrate,reduced-flavoprotein:oxygen oxidoreductase (RH-hydroxylating or -epoxidizing)
Alternative Name(s):
  • Aryl hydrocarbon hydroxylase
  • Aryl-4-monooxygenase
  • Flavoprotein monooxygenase
  • Flavoprotein-linked monooxygenase
  • Microsomal P-450
  • Microsomal monooxygenase
  • Xenobiotic monooxygenase
  • Cytochrome P450
  • Microsomal P450

EC 1.14.13.67: Quinine 3-monooxygenase

Reaction catalysed:
Quinine + NADPH + O(2) = 3-hydroxyquinine + NADP(+) + H(2)O.
Systematic name:
Quinine,NADPH:oxygen oxidoreductase
Alternative Name(s):
  • Quinine 3-hydroxylase
  • Nifedipine oxidase

EC 1.14.13.157: 1,8-cineole 2-exo-monooxygenase

Reaction catalysed:
1,8-cineole + NADPH + O(2) = 2-exo-hydroxy-1,8-cineole + NADP(+) + H(2)O.
Comments:
  • The mammalian enzyme, expressed in liver microsomes, performs a variety of oxidation reactions of structurally unrelated compounds, including stereoids, fatty acids, and xenobiotics.
  • Cf. EC 1.14.13.97, EC 1.14.13.67 and EC 1.14.13.32.
Systematic name:
1,8-cineole,NADPH:oxygen oxidoreductase (2-exo-hydroxylating)
Alternative Name(s):
  • CYP3A4

EC 1.14.13.32: Albendazole monooxygenase

Reaction catalysed:
Albendazole + NADPH + O(2) = albendazole S-oxide + NADP(+) + H(2)O.
Systematic name:
Albendazole,NADPH:oxygen oxidoreductase (sulfoxide-forming)
Alternative Name(s):
  • Albendazole oxidase
  • Albendazole sulfoxidase

Sequence family

Pfam Protein family (Pfam)
PF00067
Domain description: Cytochrome P450
Occurring in:
  1. Cytochrome P450 3A4
1 copy of Pfam domain PF00067 (Cytochrome P450) in Cytochrome P450 3A4 in PDB 4i4g.

InterPro InterPro annotations
IPR008072
Domain description: Cytochrome P450, E-class, CYP3A
Occurring in:
  1. Cytochrome P450 3A4
IPR001128
Domain description: Cytochrome P450
Occurring in:
  1. Cytochrome P450 3A4
IPR002402
Domain description: Cytochrome P450, E-class, group II
Occurring in:
  1. Cytochrome P450 3A4
IPR036396
Domain description: Cytochrome P450 superfamily
Occurring in:
  1. Cytochrome P450 3A4
IPR017972
Domain description: Cytochrome P450, conserved site
Occurring in:
  1. Cytochrome P450 3A4

Structure domain

CATH CATH domain
1.10.630.10
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Cytochrome p450
Homology: Cytochrome p450
Occurring in:
  1. Cytochrome P450 3A4
1 copy of CATH domain 1.10.630.10 (Cytochrome p450) in Cytochrome P450 3A4 in PDB 4i4g.