2gsm
Catalytic Core (Subunits I and II) of Cytochrome c oxidase from Rhodobacter sphaeroides
|
OverviewOverview
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.
About this StructureAbout this Structure
2GSM is a Protein complex structure of sequences from Rhodobacter sphaeroides with DMU, CU, MG, CA, CD, OH, HEA and TRD as ligands. Active as Cytochrome-c oxidase, with EC number 1.9.3.1 Full crystallographic information is available from OCA.
ReferenceReference
Identification of conserved lipid/detergent-binding sites in a high-resolution structure of the membrane protein cytochrome c oxidase., Qin L, Hiser C, Mulichak A, Garavito RM, Ferguson-Miller S, Proc Natl Acad Sci U S A. 2006 Oct 31;103(44):16117-22. Epub 2006 Oct 18. PMID:17050688
Page seeded by OCA on Wed Nov 21 11:21:58 2007