PROBING ELECTRON TRANSFER OF THE REDOX SPECIES IN WILD-TYPE RC PROTEIN AND ITS PIGMENT-REPLACED MUTANTS RE-CONSTITUTED IN SELF-ASSEMBLY MONOLAYERS

The multi-layered protein film, containing photosynthetic reaction center (RC) protein isolated from Rhodobacter sphaeriodes or its pigment-replaced mutants, was prepared with 4-Aminothiophenol (LF-ATP) self-assembled monolayer (SAM) modified gold electrode. The RC protein was embedded in an ordered-orientated charged poly-styrenesulfonate (PSS) and poly(dimerthyldiallylammonium) chloride (PDDA) film successively. The reversible or quasi-reversible electron transfer (ET) for the re-constituted RC and its mutants was probed by cyclic voltammetry (CV) and square wave voltammetry (SWV), reflecting the electrochemical-driven electron recombination for RC protein or its mutants. The SWV data for RC and its mutants in the films were nonlinearly fitted to get the electrochemical parameters.