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EC Number

Catalytic Site Atlas

CSA LITERATURE entry for 2b3i

E.C. nameplastoquinol---plastocyanin reductase
SpeciesProchlorothrix hollandica (Bacteria)
E.C. Number (IntEnz)
CSA Homologues of 2b3i
CSA Entries With UniProtID P50057
CSA Entries With EC Number
PDBe Entry 2b3i
PDBSum Entry 2b3i
MACiE Entry M0278

Literature Report

IntroductionPlastocyanin (PC) is a small ( 10 kDa), Type 1 copper protein that functions as an electron donor to Photosystem I (PSI) from cytochrome (cyt) f in both chloroplast systems and in some strains of cyanobacteria.
MechansimCu is coordinated in a skewed tetrahedral cage of Cys82, His39, weakly bound Met90 and His85. One side of His92 is exposed to the sovent in a region of hydrophobic residues which interact with the electron donor and acceptor. Cyt f donates one electron to oxidised PC at the Cu(II) centre forming reduced Cu(I) PC by through bond electron transfer involving His92. Reduced PC then binds to oxidised PSI where it donates an electron, reducing PSI and reforming oxidised PC.

Catalytic Sites for 2b3i

Annotated By Reference To The Literature - Site 1 (Perform Site Search)
ResidueChainNumberUniProtKB NumberFunctional PartFunctionTargetDescription
HisA85119macie:sideChainProvides a medium for the transfer of electrons to and from the Cu centre.

Literature References

Babu CR
NMR solution structure of plastocyanin from the photosynthetic prokaryote, Prochlorothrix hollandica.
Biochemistry 1999 38 4988-4995
PubMed: 10213601