1f56
From Proteopedia
SPINACH PLANTACYANIN
Overview
The crystal structure of the basic blue protein (plantacyanin) from spinach (SBP) has been solved to a resolution of 2.05 A by molecular replacement using the homologous protein from cucumber (CBP) as a model. Although the sequence identity of 58% between both proteins is only moderate, the three-dimensional structures turned out to be highly similar and the buried residues, which form the hydrophobic core of the protein, are almost completely conserved. However, the redox potentials of both proteins differ by 40 mV, and a comparison of the two structures leads to a single lysine replacing a proline in the cucumber sequence, which causes a shift of the peptide chain and thus a subtle distortion of the copper ligand geometry in respect to CBP. The crystal contained three monomers of SBP in the asymmetric unit which show considerable variations in outer loop regions owing to crystal packing, but not in the regions presumed to be essential for redox partner recognition and redox potential fine tuning of the copper centers. Still, bond length variations at the copper site are at the same scale between the monomers of SBP as they are in respect to CBP, indicating that in the oxidized state the protein does not impose a high conformational strain on the copper.
About this Structure
1F56 is a Single protein structure of sequence from Spinacia oleracea. Full crystallographic information is available from OCA.
Reference
Crystal structure of plantacyanin, a basic blue cupredoxin from spinach., Einsle O, Mehrabian Z, Nalbandyan R, Messerschmidt A, J Biol Inorg Chem. 2000 Oct;5(5):666-72. PMID:11085657 Page seeded by OCA on Fri May 2 15:54:53 2008
