Cu-Catalyzed Azide-Alkyne-Thiol Reaction Forms Ubiquitous Background in Chemical Proteomic Studies.

ABSTRACT: We report here a Cu-catalyzed azide-alkyne-thiol reaction forming thiotriazoles as the major byproduct under widely used bio-orthogonal protein labeling "click" conditions. The development of Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) had a tremendous impact on many biological discoveries. However, the considered chemoselectivity of CuAAC is hampered by the high reactivity of cysteine free thiols, yielding thiotriazole protein conjugates. The reaction byproducts generate false-positive protein hits in functional proteomic studies. The reported detail investigation of conjugates between chemical probes containing terminal alkynes, azide tags, and cell lysates reveals the formation of thiotriazoles, which can be readily detected by in-gel fluorescence scanning or after peptide and pr

SUBMITTER: Wiest A 

PROVIDER: S-EPMC10811670 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature