EC Number   |
Substrates |
Organism |
Products |
Reversibility |
|---|
   4.4.1.17 | Apocytochrome c + heme |
chorse cytochrome c, recombinant substrate with mutations D2A, E4A, K5A, G6A, K7A, K8A and F10A. For the D2A, E4A and K7A variants, heme attachment is not attenuated by the amino acid replacements. The G6A and F10A variants are not matured at detectable levels.K5A and K8A variants of horse cytochrome c are also matured at similar levels to the wild type protein |
Saccharomyces cerevisiae |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
activity of the recombinant enzyme with several mutant variants of holocytochrome c552 from Hydrogenobacter thermophilus coexpressed in Escherichia coli in cytoplasm and periplasm, respectively, and enzyme activity with several cytocohrome variants from Equus caballus in Escherichia coli cells, heme attachment motifs, overview |
Saccharomyces cerevisiae |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
conserved His154 is the key ligand to the heme iron, formation of the enzyme-heme complex serves as the platform for interaction with apocytochrome c, the heme is the central molecule mediating contact between enzyme and apocytochrome c. Conserved His19 of the CXXCH motif in apocytochrome c supplies the second axial ligand to heme in the trapped enzyme-heme-cytochrome c complex. Molecular mechanisms, overview |
Homo sapiens |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
Equus caballus heart cytochrome c or Strep-tagged Saccharomyces cerevisiae cytochrome c are coexpressed in Escherichia coli strain BL21(DE3) with Saccharomyces cerevisiae holocytochrome c synthase. No product synthesis from truncated cytochrome c1 mutants G29X, H45X and K60X, with the X indicating the position of the inserted stop codon |
Saccharomyces cerevisiae |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
the catalytic function of the enzyme depends on its ability to coordinate interactions between its substrates: heme and cytochrome c, four-step model describing enzyme-mediated cytochrome c assembly, identifying conserved histidine residue 154 as an axial ligand to the heme iron, overview. The enzyme contains two heme-binding domains, heme contacts mediated by residues within these domains modulate the dynamics of heme binding and contribute to the stability of the enzyme-heme-cytochrome c steady state ternary complex. While some residues are essential for initial heme binding, others impact the subsequent release of the holocytochrome c product |
Homo sapiens |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
the enzyme attaches heme to wild-type cytochrome, and to mutant cytochromes containing individual cysteine, histidine, and double cysteine of conserved motif CXXCH, but not the mutant with triple cysteine/histidine substitutions, overview. His19 in cytochrome c is important for 1. to provide the second axial ligand to the heme iron in preparation for covalent attachment, 2. to spatially position the two cysteinyl sulfurs adjacent to the two heme vinyl groups for thioether formation, and 3. to aid in release of the holocytochrome c from the enzyme's active site. Substitutions of His19 in cytochrome c to seven other residues (G,A,M,R,K,C,Y) show that only mutant H19M is able to carry out these three roles, albeit at lower efficiencies than the wild-type His19. The histidine in the CXXCH motif acts as an axial ligand to the heme iron |
Homo sapiens |
Holocytochrome c |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
during its import into mitochondria |
Neurospora crassa |
? |
- |
? |
| 4.4.1.17 | Apocytochrome c + heme |
enzyme for the covalent attachment of heme to apocytochrome c |
Saccharomyces cerevisiae |
? |
- |
? |
| 4.4.1.17 | apocytochrome c1 + heme |
- |
Mus musculus |
holocytochrome c1 |
- |
? |
| 4.4.1.17 | apocytochrome c1 + heme |
- |
Saccharomyces cerevisiae |
holocytochrome c1 |
- |
? |
