Cytochrome p450 3A4 is a two-domain protein. CYP3A4 has an overall fold characteristic similar to other members of the CYP family. CYP3A4 has a transmembrane domain and a transmembrane helix domain.

A transmembrane domain is a membrane- spanning helicial or beta- stranded domain embedded in a membrane. 

A transmembrane helix domain is a protein that has at least one helicial domain, a membrane- spanning domain with a hydrogen bonded helicial configuration, that includes alpha, 3-10, and pi helicies. The transmembrane alpha helix is more common, whereas the 3-10 helix, found at the end of the alpha helicies, and the pi helix are more rare. 

Structural MotifsEdit

A major conserved structural motif can be found among all cytochrome p450 proteins is the signature motif found in the heme- binding pocket that involves a cysteine ligand to the iron residue that gives the CYP family their distinctive properties. This conserved region can be seen here . The signature motif found in this particular CYP protein is found from the amino acid residue 434 to 443. 

An N- terminal hydrophobic anchor and a proline rich region that may regulate folding and substrate access are also moderately conserved among all CYP families. However, these vary in sequence and spacing, such that overall unambiguous alignment based on these structures are uncommon. 


  1. Alessandra: Cytochrome p450: Introduction
  2. Alessandra: Cytochrome p450: Biological function
  3. Alessandra: Cytochrome p450: Biosynthesis
  4. Alessandra: Cytochrome p450: Gene sequence
  5. Alessandra: Cytochrome p450: Amino acid sequence and composition
  6. Alessandra: Cytochrome p450: Secondary and tertiary structure
  7. Alessandra: Cytochrome p450: Domains and structural motifs
  8. Alessandra: Cytochrome p450: Interactions with macromolecules and small molecules
  9. Alessandra: Cytochrome p450: Molecular biodiversity and evolution
  10. Alessandra: Cytochrome p450: Literature overview
  11. Alessandra: Cytochrome p450: Useful online resources


Domain Information was found on the page for CYP3A4

Motif Information was found using the ScanProsite resource portal