|
|
| Line 1: |
Line 1: |
| [[Image:1cgn.gif|left|200px]] | | {{Seed}} |
| | [[Image:1cgn.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1cgn| PDB=1cgn | SCENE= }} | | {{STRUCTURE_1cgn| PDB=1cgn | SCENE= }} |
|
| |
|
| '''CYTOCHROME C''''
| | ===CYTOCHROME C'=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| The three-dimensional structures of two cytochromes c' have been determined in order to analyse the common features of proteins of this family and their relationship with other four-helix bundle structures. The structure of cytochrome c' from Alcaligenes sp was determined by molecular replacement supplemented with the iron anomalous scattering and the use of a single isomorphous heavy-atom derivative, and was refined using synchrotron data to 1.8 A resolution. The final model, comprising 956 protein atoms (one monomer) and 89 water molecules, has a final R value of 0.188 for all data in the range 20.0-1.8 A resolution (14 673 reflections). The structure of the cytochrome c' from Alcaligenes denitrificans is isomorphous and essentially identical (r.m.s. deviation for all atoms 0.36 A). Although its amino-acid sequence has not been determined chemically, only four differences from that of Alcaligenes sp cytochrome c' were identified by the X-ray analysis. The final model for Alcaligenes denitrificans cytochrome c', comprising 953 protein atoms and 75 water molecules, gave a final R factor of 0.167 for all data in the range 20.0-2.15 A (8220 reflections). The cytochrome c' monomer forms a classic four-helix bundle, determined by the packing of hydrophobic side chains around the enclosed haem group. There are very few cross-linking hydrogen bonds between the helices, the principal side-chain hydrogen bonding involving one of the haem propionates and a conserved Arg residue. The cytochrome c' dimer is created by a crystallographic twofold axis. Monomer-monomer contacts primarily involve the two A helices, with size complementarity of side chains in a central solvent-excluded portion of the interface and hydrogen bonding at the periphery. Both species have a pyroglutamic acid N-terminal residue. The haem iron is five-coordinate, 0.32 A out of the haem plane towards the fifth ligand, His120. The unusual magnetic properties of the Fe atom may be linked to a conserved basic residue, Arg124, adjacent to His120. | | The line below this paragraph, {{ABSTRACT_PUBMED_15299707}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 15299707 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_15299707}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| Line 26: |
Line 30: |
| [[Category: Dobbs, A J.]] | | [[Category: Dobbs, A J.]] |
| [[Category: Faber, H R.]] | | [[Category: Faber, H R.]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 12:42:56 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 20:43:23 2008'' |
