Hemin/G-quadruplex (hGQ) DNAzymes are horseradish peroxidase-mimicking catalysts capable of the oxidation of a variety of substrates. We now implement aptamer-functionalized hGQ DNAzymes, also known as nucleoapzymes, to achieve increased bioconjugation of N-methyl luminol to tyrosinecontaining residues and peptides. We found that the presence of a tyrosinamide-binding aptamer leads to a 12-fold increase in the catalytic rate constant (k cat ), and the saturation kinetics curves that were obtained provide evidence for the involve-ment of the substrate binding site in the reaction. The application of the best performing nucleoapzymes for the modification of Tyr-containing peptides reveals that (i) the aptamer also recognizes the ligand structure when this is embedded in a larger peptide structure, and (ii) distant residues in the peptide substrate can influence the conversion. As such, we show that nucleoapzymes display enzyme-like features and provide an additional tool in the toolbox of bioconjugation chemistry.