Proteorhodopsin Expression and Purification Anaerobic growth Proton-pumping measurements Solar mimicking apparatus Toxicity test by serial dilutions ATP assay 15-15' Beta-carotene dioxygenase (BLH) Cell growth Extraction of pigments TLC UV-VIS HPLC Nicotinic Phosphoribosyl Transferase (pncB) NAD/NADH quantification pMFC Berkley bacteria growth pMFC data logging