Membrane-Anchored DNA Assembly for Energy and Electron Transfer

Abstract

In this work we examine the trapping and conversion of visible light energy into chemical energy using a supramolecular assembly. The assembly consists of a light-absorbing antenna and a porphyrin redox centre which are covalently attached to two complementary 14-mer DNA strands, hybridized to form a double helix and anchored to a lipid membrane. The excitation energy is finally trapped in the lipid phase of the membrane as a benzoquinone radical anion that could potentially be used in subsequent chemical reactions. In addition, in this model complex the hydrophobic porphyrin moiety acts as an anchor into the liposome positioning the DNA construct on the lipid membrane surface. The results show the suitability of our system as a prototype for DNA based light-harvesting devices, in which energy transfer from the aqueous phase to the interior of the lipid membrane is followed by charge separation.

Soft‐Surface DNA Nanotechnology: DNA Constructs Anchored and Aligned to Lipid Membrane

“…The porphyrin moiety is not merely an anchor, but also a multifunctional unit with both the ability to communicate with the surface and probe the binding strength to the membrane, features we have investigated in previous work. [3]…”

Self‐Assembled DNA‐Based Fluorescence Waveguide with Selectable Output

“…This feature could be used in conjunction with other functions relying on excitation energy as a driving force. One possible use is to create a system for controlled nanoscale reactions by coupling the multistep energy transfer to electron transfer 31, 32…”

Nucleotides and nucleic acids; oligo- and polynucleotides

“…182 A zinc-porphyrin complex has been added to C5 of dU for use in electron transfer. 183 Norbornene has been attached via an alkyne linker for post-synthetic modification with nitrile oxides in a copper-free Click reaction, 184 and various dienes have been attached for Diels-Alder tagging of DNA. 185 The photoaffinity tag (41) has been incorporated into DNA adjacent to a damaged DNA base (8-oxo-dG or thymine dimer) such that when exposed to repair systems, the repair enzyme is trapped by the diazirine for mass spectroscopic characterisation.…”

“…103 Diphenyl-and tetraphenylporphyrin derivatives as Zn(II) complexes have been attached to C5 of a pyrimidine to act as a zipper-structure in duplex DNA, and for energy transfer studies. 183,520 A number of metal complexes have been conjugated to the termini of oligonucleotides, such as the Co(III) Schiff base conjugate (88) which was used as an inhibitor of zinc finger transcription factors. 521 Ironporphyrin complexes have been conjugated to the end of oligonucleotides where they were found to modulate the activity of horseradish peroxidase by up to 100-fold depending upon the sequence of the tethered oligonucleotide.…”

“…542 Other methods of inducing DNA charge transfer include the use of intercalating Rh(III) 543 or Ru(II) 544 complexes, 2'-O-pyrene-modified uridine, 545 or a pyrene endcap, 546 and C5-porphyrin-modified dU. 183 A 2'-O-modified nitrobenzene uridine derivative has been used as an electron acceptor. 545 Various nucleoside analogues have been used as electron donors or acceptors, for example 2-aminopurine 547 and the novel pyrimidine analogue (90), 548 and 5-bromo-dU as electron acceptor.…”