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DNA-Catalyzed Introduction of Azide at Tyrosine for Peptide Modification.

ABSTRACT: We show that DNA enzymes (deoxyribozymes) can introduce azide functional groups at tyrosine residues in peptide substrates. Using in vitro selection, we identified deoxyribozymes that transfer the 2'-azido-2'-deoxyadenosine 5'-monophosphoryl group (2'-Az-dAMP) from the analogous 5'-triphosphate (2'-Az-dATP) onto the tyrosine hydroxyl group of a peptide, which is either tethered to a DNA anchor or free. Some of the new deoxyribozymes are general with regard to the amino acid residues surrounding the tyrosine, while other DNA enzymes are sequence-selective. We use one of the new deoxyribozymes to modify free peptide substrates by attaching PEG moieties and fluorescent labels.

SUBMITTER: Wang P

PROVIDER: S-EPMC4993102 | biostudies-literature |

REPOSITORIES: biostudies-literature

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DNA-catalyzed covalent modification of amino acid side chains in tethered and free peptide substrates.

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