Phototriggered DNA phosphoramidate ligation in a tandem 5'-amine deprotection/3'-imidazole activated phosphate coupling reaction

Bioconjug Chem. 2012 Oct 17;23(10):2014-9. doi: 10.1021/bc300093y. Epub 2012 Sep 26.

Abstract

We report the preparation and use of an N-methyl picolinium carbamate protecting group for applications in a phototriggered nonenzymatic DNA phosphoramidate ligation reaction. Selective 5'-amino protection of a modified 13-mer oligonucleotide is achieved in aqueous solution by reaction with an N-methyl-4-picolinium carbonyl imidazole triflate protecting group precursor. Deprotection is carried out by photoinduced electron transfer from Ru(bpy)(3)(2+) using visible light photolysis and ascorbic acid as a sacrificial electron donor. Phototriggered 5'- amino oligonucleotide deprotection is used to initiate a nonenzymatic ligation of the 13-mer to an imidazole activated 3'-phospho-hairpin template to generate a ligated product with a phosphoramidate linkage. We demonstrate that this methodology offers a simple way to exert control over reaction initiation and rates in nonenzymatic DNA ligation for potential applications in the study of model protocellular systems and prebiotic nucleic acid synthesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amides / chemistry*
  • Amines / chemistry*
  • Base Sequence
  • DNA / chemistry*
  • DNA / genetics
  • Imidazoles / chemistry*
  • Oligodeoxyribonucleotides / chemistry
  • Oligodeoxyribonucleotides / genetics
  • Phosphates / chemistry*
  • Phosphoric Acids / chemistry*
  • Photochemical Processes*

Substances

  • Amides
  • Amines
  • Imidazoles
  • Oligodeoxyribonucleotides
  • Phosphates
  • Phosphoric Acids
  • imidazole
  • DNA
  • phosphoramidic acid