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Stable Europium(III) Complexes with Short Linkers for Site-Specific Labeling of Biomolecules.

ABSTRACT: In this study, two new terpyridine-based EuIII complexes were synthesized, the structures of which were optimized for luminescence resonance energy-transfer (LRET) experiments. The complexes showed high quantum yields (32?%); a single long lifetime (1.25?ms), which was not influenced by coupling to protein; very high stability in the presence of chelators such as ethylenediamine-N,N,N',N'-tetraacetate and ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid; and no interaction with cofactors such as adenosine triphosphate and guanosine triphosphate. A special feature is the short length of the linker between the EuIII ion and the maleimide or hydrazide function, which allows for site-specific coupling of cysteine mutants or unnatural keto amino acids. As a consequence, the new complexes appear particularly suited for accurate distance measurements in biomolecules by LRET.

SUBMITTER: Faschinger F

PROVIDER: S-EPMC5715356 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Stable Europium(III) Complexes with Short Linkers for Site-Specific Labeling of Biomolecules.

Faschinger Felix F Ertl Martin M Zimmermann Mirjam M Horner Andreas A Himmelsbach Markus M Schöfberger Wolfgang W Knör Günther G Gruber Hermann J HJ

ChemistryOpen 20170904 6

In this study, two new terpyridine-based EuIII complexes were synthesized, the structures of which were optimized for luminescence resonance energy-transfer (LRET) experiments. The complexes showed high quantum yields (32 %); a single long lifetime (1.25 ms), which was not influenced by coupling to protein; very high stability in the presence of chelators such as ethylenediamine-N,N,N',N'-tetraacetate and ethylene glycol-bis(2-aminoethylether)-N,N ...[more]

PMID: 29226060

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