Figure 5 - full size

 

Figure 5.
Figure 5: Electron transfer chain and plastocyanin binding. Residues 18 -47 of plant PsaF, which include the 18 residues exclusive to eukaryotes and that form a helix -loop -helix domain, are coloured red. A cluster of four negatively charged residues (red) on the surface of plastocyanin (green) interacts with three lysines (blue) from the N terminus of PsaF, two of which are from the extra 18 residues. The two tryptophan residues (indicated by an arrow) crucial for the electron transfer from the reduced copper to the oxidized P[700], and that contribute to the hydrophobic interaction with plastocyanin, are shown as spherical atoms (cyan and magenta). The histidine residue that coordinates the copper atom in plastocyanin is in blue.

The above figure is reprinted by permission from Macmillan Publishers Ltd: Nature (2003, 426, 630-635) copyright 2003.