Figure 9.

Two modes of predicted usefulness for Cu²⁺-utilizing, CuAAC-catalyzing DNAzymes. (A) The usefulness of in cis conjugation of the existing ≡-CLICK-17 DNAzyme, with covalently appended multiple fluorescent (as well as other) labels, to an azide-incorporating cell surface marker, ‘a’. (B) Orthogonal labeling cell surface determinants. In this schematic, the high substrate specificity that DNA enzymes are known to be capable of, is invoked. Here, a substrate-specific ‘DNAzyme I’ would specifically couple an azide-derivatized cell surface determinant (‘a’) with an alkyne-labeled tag, ‘c’, but not with an azide-derivatized cell surface determinant (‘b’) with an alkyne-labeled tag, ‘d’. Conversely, a different enzyme, ‘DNAzyme II’ would exclusively couple an azide-derivatized cell surface determinant (‘b’) with alkyne-‘d’ and not ‘a’ with ‘c’.