Engineering Photosystem i Complexes with Metal Oxide Binding Peptides for Bioelectronic Applications
Conventional dye-sensitized solar cells comprise semiconducting anodes sensitized with complex synthetic organometallic dyes, a platinum counter electrode, and a liquid electrolyte. This work focuses on replacing synthetic dyes with a naturally occurring biological pigment-protein complex known as Photosystem I (PSI). Specifically, ZnO binding peptides (ZOBiP)-fused PSI subunits (ZOBiP-PsaD and ZOBiP-PsaE) and TiO2 binding peptides (TOBiP)-fused ferredoxin (TOBiP-Fd) have been produced recombinantly from Escherichia coli. The MOBiP-fused peptides have been characterized via western blotting, circular dichroism, MALDI-TOF, and cyclic voltammetry. ZOBiP-PSI subunits have been used to replace wild-type PsaD and PsaE, and TOBiP-Fd has been chemically cross-linked to the stromal hump of PSI. These MOBiP peptides and MOBiP-PSI complexes have been produced and incubated with various metal oxide nanoparticles, showing increased binding when compared to that of wild-type PSI complexes.
Simmerman, R., Zhu, T., Baker, D., Wang, L., Mishra, S., Lundgren, C., & Bruce, B. (2015). Engineering Photosystem i Complexes with Metal Oxide Binding Peptides for Bioelectronic Applications. Bioconjugate Chemistry, 26 (10), 2097-2105. https://doi.org/10.1021/acs.bioconjchem.5b00374