2GSM: Catalytic Core (subunits I And Ii) Of Cytochrome C Oxidase From Rhodobacter Sphaeroides

Citation:
Abstract
Well ordered reproducible crystals of cytochrome c oxidase (CcO) from Rhodobacter sphaeroides yield a previously unreported structure at 2.0 A resolution that contains the two catalytic subunits and a number of alkyl chains of lipids and detergents. Comparison with crystal structures of other bacterial and mammalian CcOs reveals that the positions occupied by native membrane lipids and detergent substitutes are highly conserved, along with amino acid residues in their vicinity, suggesting a more prevalent and specific role of lipid in membrane protein structure than often envisioned. Well defined detergent head groups (maltose) are found associated with aromatic residues in a manner similar to phospholipid head groups, likely contributing to the success of alkyl glycoside detergents in supporting membrane protein activity and crystallizability. Other significant features of this structure include the following: finding of a previously unreported crystal contact mediated by cadmium and an engineered histidine tag; documentation of the unique His-Tyr covalent linkage close to the active site; remarkable conservation of a chain of waters in one proton pathway (D-path); and discovery of an inhibitory cadmium-binding site at the entrance to another proton path (K-path). These observations provide important insight into CcO structure and mechanism, as well as the significance of bound lipid in membrane proteins.
PDB ID: 2GSMDownload
MMDB ID: 42220
PDB Deposition Date: 2006/4/26
Updated in MMDB: 2006/12
Experimental Method:
x-ray diffraction
Resolution: 2  Å
Source Organism:
Similar Structures:
Biological Unit for 2GSM: dimeric; determined by author and by software (PISA,PQS)
Molecular Components in 2GSM
Label Count Molecule
Proteins (2 molecules)
1
Cytochrome C Oxidase Subunit 1
Molecule annotation
1
Cytochrome C Oxidase Subunit 2
Molecule annotation
Chemicals (20 molecules)
1
5
2
3
3
1
4
1
5
1
6
2
7
5
8
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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