title: Regulation of photosensitisation processes by an RNA aptamer.
abstract: One of the most powerful attributes of proteins is their ability to bind to and modulate the chemistry of cofactors and prosthetic groups. Here, we demonstrated the ability of an artificial nucleic acid (an aptamer) to similarly control the functionality of a non-biological element. Specifically, we selected an RNA aptamer that binds tris(bipyridine) ruthenium (II), Ru(bpy)32+, an inorganic complex that has attracted intense interest due to its photoredox chemistry, including its ability to split water by visible light. We found that a newly discovered aptamer strongly and enantioselectively binds Λ-Ru(bpy)32+(Kd= 65 nM) and, in doing so, selectively suppresses deactivation via energy transfer, thereby elongating the lifetime of its photo-excited state by four-fold. The ability of the aptamer to enhance this important aspect of Ru(bpy)32+chemistry illustrates a broader point concerning the potential power of combining in vitro-created biomolecules with non-biological reactants to perform enhanced chemical reactions.
authors.affiliation: Nano Medical Engineering Laboratory, RIKEN, Wako, Saitama, Japan.|Department of Biological Science, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.|Center for Molecular Biology, Duy Tan University, P402, K7/25 Quang Trung, Danang, Vietnam.
authors.forename: Tran Thi Thanh
authors.initials: TT
authors.lastname: Thoa
authors.affiliation: Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Minagawa
authors.affiliation: Department of Biological Science, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Aigaki
authors.affiliation: Nano Medical Engineering Laboratory, RIKEN, Wako, Saitama, Japan.|Department of Biological Science, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.|Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Nano Medical Engineering Laboratory, RIKEN, Wako, Saitama, Japan.|Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Uzawa
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002151:Calorimetry; D009942:Organometallic Compounds / Q000737:chemistry*; D055668:Photochemical Processes; D013816:Thermodynamics
chemical_list: D052157:Aptamers, Nucleotide; D009942:Organometallic Compounds; C415768:tris(2,2'-bipyridyl)ruthenium(II)