Activating Compound | Comment | Organism | Structure |
---|---|---|---|
additional information | at low molar ratios of cytochrome b5 to cytochrome P450 reductase, the more rapid catalysis results in enhanced substrate metabolism. In contrast, at high molar ratios of cytochome b5 to cytochrome P450 reductase, cytochrome b5 inhibits activity by binding to the proximal surface of cytochrome P450 and preventing the reductase from reducing ferric cytochrome P450 to the ferrous protein, thereby aborting the catalytic reaction cycle. Cytochrome b5 stimulates catalysis by causing a conformational change in the active site, which allows the active oxidizing oxyferryl species of cytochrome P450 to be formed more rapidly than in the presence of reductase | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
additional information | deletion of 11 amino acids of the membrane anchor yields a cytosolic protein that does not bind to the endoplasmic reticulum, whereas lengthening the membrane anchor by 5 amino acids causes the protein to be transported to the plasma membrane of COS cells | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | at low molar ratios of cytochrome b5 to cytochrome P450 reductase, the more rapid catalysis results in enhanced substrate metabolism. In contrast, at high molar ratios of cytochome b5 to cytochrome P450 reductase, cytochrome b5 inhibits activity by binding to the proximal surface of cytochrome P450 and preventing the reductase from reducing ferric cytochrome P450 to the ferrous protein, thereby aborting the catalytic reaction cycle | Homo sapiens |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | cytochrome b5 is a membrane-bound protein that is inserted into the membrane via an alpha-helix at its carboxy terminus. A random-coil linker of 15 amino acids connects the acidic soluble cytosolic heme domain to the membrane anchor | Homo sapiens | 16020 | - |
microsome | - |
Homo sapiens | - |
- |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | Homo sapiens | binding of cytochrome P450 2B4 to cytochrome b5 and cytochrome P450 reductase, binding site on cytochrome P450 2B4 for its redox partners, complex formation modelling, overview | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
liver | - |
Homo sapiens | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | binding of cytochrome P450 2B4 to cytochrome b5 and cytochrome P450 reductase, binding site on cytochrome P450 2B4 for its redox partners, complex formation modelling, overview | Homo sapiens | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
cytochrome P450 reductase | - |
Homo sapiens |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | - |
Homo sapiens | |
FMN | - |
Homo sapiens | |
additional information | cytochrome P450 reductase is a membrane-bound diflavin protein, which transfers two electrons sequentially from NADPH through FAD to the FMN cofactor, which is the ultimate donor of electrons to cytochrome P450 and other acceptor proteins | Homo sapiens | |
NADPH | - |
Homo sapiens |
General Information | Comment | Organism |
---|---|---|
additional information | cytochrome P450 reductase is a membrane-bound diflavin protein, which transfers two electrons sequentially from NADPH through FAD to the FMN cofactor, which is the ultimate donor of electrons to cytochrome P450 and other acceptor proteins | Homo sapiens |