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Modular and tunable chemosensor scaffold for divalent zinc.

Melissa D Shults·Dierdre A Pearce·Barbara Imperiali
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Abstract

A modular peptide scaffold has been developed for fluorescent sensing of divalent zinc. The signaling component of the chemosensor is the chelation-sensitive fluorophore 8-hydroxy-5-(N,N-dimethylsulfonamido)-2-methylquinoline, which is prepared as the protected amino acid derivative Fmoc-Sox-OH and integrated into peptide sequences. Nineteen synthetic peptides incorporating the signaling element exhibit a range of affinities for Zn(2+) through variation of the type and number of Zn(2+) ligands, ligand arrangement and the beta-turn sequence that acts as a preorganization element between the ligands. The stoichiometry of the peptide-Zn(2+) complexes is evaluated by several criteria. The fluorescence response of these peptides to pH and various important metal ions is reported. Eleven of these sequences form only 1:1 complexes with Zn(2+) and their affinities range from 10 nM to nearly 1 microM. When used in concert, these sensors can provide Zn(2+) concentration information in a valuable range.

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Amino AcidsBiosensing TechniquesCations, DivalentFluorenesFluorescent DyesHydrogen-Ion ConcentrationKineticsOligopeptidesQuinolinesSpectrometry, FluorescenceSulfonamidesZincJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Melissa D Shults, Dierdre A Pearce, Barbara Imperiali. 2003-09-03. Modular and tunable chemosensor scaffold for divalent zinc.. https://doi.org/10.1021/ja0355980

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