Figure 4

Structural model of an H-bond network around P840 in the L688C and the V689C RCs.
The structural model was constructed with the mutated PsaA in which Thr-742 and Thr-743 were substituted with cysteine residues, to show the artificially introduced H-bond network in the L688C and V689C RCs. The modelling was performed by the homology modelling program MODELLER (ver. 9.1550), using the X-ray structure of PS I (PDB ID: 1JB09) as a template.