Catalytic core subunits (I and II) of cytochrome c oxidase from Rhodobacter sphaeroides in the reduced state

Redox dependent conformational changes in cytochrome c oxidase suggest a gating mechanism for proton uptake.

Cytochrome c oxidase polypeptide I, Cytochrome aa3 subunit 1

Cytochrome c oxidase polypeptide II, Cytochrome aa3 subunit 2, Oxidase aa(3) subunit 2

MADAAIHGHEHDRRGFFTRWFMSTNHKDIGVLYLFTGGLVGLISVAFTVYMRMELMAPGVQFMCAEHLESGLVKGFFQSL
WPSAVENCTPNGHLWNVMITGHGILMMFFVVIPALFGGFGNYFMPLHIGAPDMAFPRMNNLSYWLYVAGTSLAVASLFAP
GGNGQLGSGIGWVLYPPLSTSESGYSTDLAIFAVHLSGASSILGAINMITTFLNMRAPGMTMHKVPLFAWSIFVTAWLIL
LALPVLAGAITMLLTDRNFGTTFFQPSGGGDPVLYQHILWFFGHPEVYIIVLPAFGIVSHVIATFAKKPIFGYLPMVYAM
VAIGVLGFVVWAHHMYTAGLSLTQQSYFMMATMVIAVPTGIKIFSWIATMWGGSIELKTPMLWALGFLFLFTVGGVTGIV
LSQASVDRYYHDTYYVVAHFHYVMSLGAVFGIFAGIYFWIGKMSGRQYPEWAGKLHFWMMFVGANLTFFPQHFLGRQGMP
RRYIDYPEAFATWNFVSSLGAFLSFASFLFFLGVIFYTLTRGARVTANNYWNEHADTLEWTLTSPPPEHTFEQLPKREDW
ERAPAH

QQQSLEIIGRPQPGGTGFQPSASPVATQIHWLDGFILVIIAAITIFVTLLILYAVWRFHEKRNKVPARFTHNSPLEIAWT
IVPIVILVAIGAFSLPVLFNQQEIPEADVTVKVTGYQWYWGYEYPDEEISFESYMIGSPATGGDNRMSPEVEQQLIEAGY
SRDEFLLATDTAMVVPVNKTVVVQVTGADVIHSWTVPAFGVKQDAVPGRLAQLWFRAEREGIFFGQCSELCGISHAYMPI
TVKVVSEEAYAAWLEQHHHHHH

23-24% PEG-400, crystal reduced by dithionite, pH 6.3, VAPOR DIFFUSION, SITTING DROP, temperature 277K

Catalytic core subunits (I and II) of cytochrome c oxidase from Rhodobacter sphaeroides in the reduced state bound with cyanide

Catalytic Core (Subunits I and II) of Cytochrome c oxidase from Rhodobacter sphaeroides

(1) THERE IS A COVALENT LINKAGE
BETWEEN NE2 OF HIS284 OF SUBUNIT I AND CE2 OF TYR288 OF
SUBUNIT I. (2) THERE IS RESIDUAL DENSITY IN (FO-FC) DIFFERENCE
FOURIER MAP AT THE MAGNESIUM SITES IN BOTH MOLECULES AND THE B
-FACTOR FOR EACH MAGNESIUM ION IS UNUSUALLY LOW. THESE
OBSERVATIONS SUGGEST THAT THIS MAGNESIUM SITE MAY BE PARTIALLY
OCCUPIED BY A HEAVIER METAL ION IN THE PROTEIN CRYSTAL. (3)
THE SIDE CHAINS OF THE FOLLOWING RESIDUES ARE NOT FULLY
RESOLVED. THE UNRESOLVED SIDE CHAIN ATOMS ARE ASSIGNED AN
OCCUPANCY OF 0.00 AND AN ARBITORY B-FACTOR OF 100.00: PHE-A-17
THR-A-18 ARG-A-19 LYS-A-74 LYS-A-224 GLU-A-548 LYS-B-86
GLU-B-131 LYS-C-74 ARG-C-137 LYS-C-224 GLU-C-548 HIS-C-549
LYS-D-86 HIS-D-284 (4) LIGANDS LABELLED AS TRD ARE ALL
ALKYL CHAINS (WITH DIFFERENT LENGTHS) OF EITHER DMU OR NATIVE
MEMBRANE LIPIDS SUCH AS PHOSPHATIDYL ETHANOLAMINE OR
CARDIOLIPIN. SOME OF THE DETERGENTS LABELLED AS DMU DO NOT
CONTAIN THE CARBON CHAIN, OR THE DISTAL GLUCOSE MOIETY. THE
AUTHORS DO NOT KNOW FOR SURE THE IDENTITIES OF THE COMPLETE
MOLECULES YET. (5) THERE IS AN UNKOWN ATOM OR ION NEAR HIS26
AND THR550 OF SUBUNIT I.

conformational changes, Cell membrane, Copper, Electron transport, Heme, Hydrogen ion transport, Ion transport, Iron, Membrane, Metal-binding, Respiratory chain, Transmembrane, Transport, OXIDOREDUCTASE

QQQSLEIIGRPQPGGTGFQPSASPVATQIHWLDGFILVIIAAITIFVTLLILYAVWRFHEKRNKVPARFTHNSPLEIAWT
IVPIVILVAIGAFSLPVLFNQQEIPEADVTVKVTGYQWYWGYEYPDEEISFESYMIGSPATGGDNRMSPEVEQQLIEAGY
SRDEFLLATDTAMVVPVNKTVVVQVTGADVIHSWTVPAFGVKQDAVPGRLAQLWFRAEREGIFFGQCSELCGISHAYMPI
TVKVVSEEAYAAWLEQ