Modelling Photosynthesis with ZnII‐Protoporphyrin All‐DNA G‐Quadruplex/Aptamer Scaffolds

Abstract All‐DNA scaffolds act as templates for the organization of photosystem I model systems. A series of DNA templates composed of Zn II ‐protoporphyrin IX (Zn II PPIX)‐functionalized G‐quadruplex conjugated to the 3′‐ or 5′‐end of the tyrosinamide (TA) aptamer and Zn II PPIX/G‐quadruplex linked to the 3′‐ and 5′‐ends of the TA aptamer through a four‐thymidine bridge. Effective photoinduced electron transfer (ET) from Zn II PPIX/G‐quadruplex to bipyridinium‐functionalized tyrosinamide, TA‐MV 2+ , bound to the TA aptamer units is demonstrated. The effectiveness of the primary ET quenching of Zn II PPIX/G‐quadruplex by TA‐MV 2+ controls the efficiency of the generation of TA‐MV +. . The photosystem‐controlled formation of TA‐MV +. by the different photosystems dictates the secondary activation of the ET cascade corresponding to the ferredoxin‐NADP + reductase (FNR)‐catalysed reduction of NADP + to NADPH by TA‐MV +. , and the sequestered alcohol dehydrogenase catalysed reduction of acetophenone to 1‐phenylethanol by NADPH.