A Genetically Encoded Picolyl Azide for Improved Live Cell Copper Click Labeling.

Meineke B, Heimgärtner J, Craig AJ, Landreh M, Moodie LWK, Elsässer SJ

Front Chem 9 (-) 768535 [2021-11-11; online 2021-11-11]

Bioorthogonal chemistry allows rapid and highly selective reactivity in biological environments. The copper-catalyzed azide-alkyne cycloaddition (CuAAC) is a classic bioorthogonal reaction routinely used to modify azides or alkynes that have been introduced into biomolecules. Amber suppression is an efficient method for incorporating such chemical handles into proteins on the ribosome, in which noncanonical amino acids (ncAAs) are site specifically introduced into the polypeptide in response to an amber (UAG) stop codon. A variety of ncAA structures containing azides or alkynes have been proven useful for performing CuAAC chemistry on proteins. To improve CuAAC efficiency, biologically incorporated alkyne groups can be reacted with azide substrates that contain copper-chelating groups. However, the direct incorporation of copper-chelating azides into proteins has not been explored. To remedy this, we prepared the ncAA paz-lysine (PazK), which contains a picolyl azide motif. We show that PazK is efficiently incorporated into proteins by amber suppression in mammalian cells. Furthermore, PazK-labeled proteins show improved reactivity with alkyne reagents in CuAAC.

SciLifeLab Fellow

Simon Elsässer

PubMed 34858945

DOI 10.3389/fchem.2021.768535

Crossref 10.3389/fchem.2021.768535

pii: 768535
pmc: PMC8632528

Publications 9.5.0