title: Synthesis of red-shifted 8-hydroxyquinoline derivatives using click chemistry and their incorporation into phosphorylation chemosensors.
abstract: 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 Mg(2+) 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).
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge,Massachusetts 02139, USA.
authors.forename: Juan A
authors.initials: JA
authors.lastname: González-Vera
authors.forename: Elvedin
authors.initials: E
authors.lastname: Luković
authors.forename: Barbara
authors.initials: B
authors.lastname: Imperiali
mesh_terms: D005456:Fluorescent Dyes / Q000737:chemistry*; D015394:Molecular Structure; D015125:Oxyquinoline / Q000138:chemical synthesis* / Q000737:chemistry; D010766:Phosphorylation; D013237:Stereoisomerism
chemical_list: D005456:Fluorescent Dyes; D015125:Oxyquinoline