Synthesis of Red-Shifted 8-Hydroxyquinoline Derivatives Using Click Chemistry and Their Incorporation into Phosphorylation Chemosensors

Protein phosphorylation is a ubiquitous post-translational modification, and protein kinases, the enzymes that catalyze the phosphoryl transfer, are involved in nearly every aspect of normal, as well as aberrant, cell function. Here we describe the synthesis of novel, red-shifted 8-hydroxyquinoline-...

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Bibliographic Details
Main Authors: Gonzalez-Vera, Juan A., Lukovic, Elvedin, Imperiali, Barbara
Other Authors: Massachusetts Institute of Technology. Department of Biology
Format: Article
Language:en_US
Published: American Chemical Society 2012
Online Access:http://hdl.handle.net/1721.1/69597
https://orcid.org/0000-0002-5749-7869
Description
Summary:Protein phosphorylation is a ubiquitous post-translational modification, and protein kinases, the enzymes that catalyze the phosphoryl transfer, are involved in nearly every aspect of normal, as well as aberrant, cell function. Here we describe the synthesis of novel, red-shifted 8-hydroxyquinoline-based fluorophores and their incorporation into peptidyl kinase activity reporters. Replacement of the sulfonamide group of the sulfonamido-oxine (1, Sox) chromophore, which has been previously used in kinase sensing, by a 1,4-substituted triazole moiety prepared via click chemistry resulted in a significant bathochromic shift in the fluorescence excitation (15 nm) and emission (40 nm) maxima for the Mg2+ chelate. Furthermore, when a click derivative was incorporated into a chemosensor for MK2, the kinase accepted the new substrate as efficiently as the previously reported Sox-based sensor. Taken together, these results extend the utility range of kinase sensors that are based on chelation-enhanced fluorescence (CHEF).