An enzyme-coupled artificial photosynthesis system prepared from antenna protein-mimetic tyrosyl bolaamphiphile self-assembly

Abstract

An artificial photosynthesis system coupled with an enzyme was constructed using the nanospherical self-assembly of tyrosyl bolaamphiphiles, which worked as a host matrix exhibiting an antenna effect that allowed enhanced energy transfer to the ZnDPEG photosensitizer. The excited electrons from the photosensitizer were transferred to NAD+ to produce NADH, which subsequently initiated the conversion of an aldehyde to ethanol by alcohol dehydrogenase. Production of NADH and ethanol was enhanced by increasing the concentration of tyrosyl bolaamphiphiles. Spectroscopic investigations proved that the photosensitizer closely associated with the surface of the bolaamphiphile assembly through hydrogen bonds that allowed energy transfer between the host matrix and the photosensitizer. This study demonstrates that the self-assembly of bolaamphiphiles could be applicable to the construction of biomimetic energy systems exploiting biochemical activity.

Photobiocatalysis: Activating Redox Enzymes by Direct or Indirect Transfer of Photoinduced Electrons

“…They have strong absorption in the visible light range,g iving them intrinsic advantages as ap hotosensitizer.F or example,z inc porphyrins (e.g.,z inc tetraphenylporphyrin tetrasulfonate,z inc tetramethylpyridinium porphyrin) have remarkably long lifetimes in the triplet excited state,w hich have been utilized for biocatalytic photosynthesis. [22][23][24][25] Xanthenes (e.g., eosin Y, rose bengal) are low-cost, metal-free dyes that absorb visible lights (500-600 nm) to generate photoexcited electrons with as inglettriplet transition. [26] They have been used for direct (or indirect) transfer of electrons to active sites of redox catalysts.…”

Photoinduced Intermolecular Electron Transfer Mediated by the Colloidal Tyrosyl Bolaamphiphile Assembly

“…TyrBA displayed biochemical activities of the tyrosine phenol groups and exhibited outstanding mechanical strength that originated from intermolecular interactions, such as hydrophobic interactions and hydrogen bonds. Furthermore, heterogeneous molecules can associate with TyrBA through intermolecular forces for diverse chemical activities . These biochemical and colloidal properties suggest that TyrBA could be a feasible platform with surface‐exposed tyrosyl phenol groups that can be utilized as a mimic of Tyr Z to construct a PSII mimetic system with an electron relay function.…”

“…Furthermore, heterogeneous molecules can associate with TyrBA through intermolecular forces ford iverse chemicala ctivities. [19] These biochemical and colloidal properties suggestt hat TyrBA could be af easible platform with surface-exposed tyrosyl phenol groups that can be utilized as a mimic of Tyr Z to construct aP SII mimetic system with an electron relay function.…”

Photobiokatalyse: Aktivierung von Redoxenzymen durch direkten oder indirekten Transfer photoinduzierter Elektronen

“…Über eine Elektronentransferkaskade,d as sogenannte "Z-Schema", werden diese in Form von NADPH und Adenosintriphosphat (ATP) gespeichert. [22][23][24][25] Xanthenbasierte Farbstoffe (wie Eosin Yund Bengalrosa) sind kostengünstige, metallfreie Farbstoffe,w elche im Bereich sichtbaren Lichts absorbieren (500-600 nm) und so über einen Singulett-Triplett-Übergang photoangeregte Elektronen erzeugen. Durch niveaus wichtiger biokatalytischer Redoxvorgänge.D a Chlorophylle eine Schlüsselrolle als Lichtsammelpigmente in der natürlichen Photosynthese spielen und diese Farbstoffe Porphyrine enthalten, werden Porphyrine vielfach als Bausteine fürd ie künstliche Photosynthese eingesetzt.…”

“…So zeigen beispielsweise Zinkporphyrine (wie Zinktetraphenylporphyrintetrasulfonat oder Zinktetramethylpyridiniumporphyrin) bemerkenswert lange Lebenszeiten in ihren angeregten Tr iplettzuständen und werden entsprechend bereits fürd ie biokatalytische Photosynthese eingesetzt. [22][23][24][25] Xanthenbasierte Farbstoffe (wie Eosin Yund Bengalrosa) sind kostengünstige, metallfreie Farbstoffe,w elche im Bereich sichtbaren Lichts absorbieren (500-600 nm) und so über einen Singulett-Triplett-Übergang photoangeregte Elektronen erzeugen. [26] Xanthenderivate werden sowohl zum direkten als auch zum indirekten Elektronentransfer zum aktiven Zentrum von Redoxkatalysatoren eingesetzt.…”