Fabrication of a photoelectronic device by direct chemical binding of the photosynthetic reaction center protein to metal surfaces

A system that overcame the problems arising from direct covalent binding of proteins to metal surfaces was devised. The robust photosystem I (PS I) reaction centers from the cyanobacteria. The PS I monomer of the cysteine mutant D479C readily formed self-assembled, oriented monolayers. The CPD of the PS I monomer monolayer obtained by KPFM measurements in the dark describes a continuum. It was demonstrated that selection of a robust reaction center PS I from cyanobacteria and rational design of mutations based on the crystallographic structure enable the fabrication of an oriented monolayer on a conducting metal surface. The dry-membrane protein in the monolayer retained its capacity to generate a photopotential of approximately +1 V.