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Intramolecular substitution uncages fluorogenic probes for detection of metallo-carbapenemase-expressing bacteria.

ABSTRACT: This work reports a novel caging strategy for designing fluorogenic probes to detect the activity of ?-lactamases. The caging strategy uses a thiophenyl linker connected to a fluorophore caged by a good leaving group-dinitrophenyl. The uncaging proceeds in two steps through the sulfa-releasing and subsequent intramolecular substitution. The length of the linker has been examined and optimized to maximize the rate of intramolecular reaction and thus the rate of fluorescence activation. Finally based on this strategy, we prepared a green fluorogenic probe CAT-7 and validated its selectivity for detecting metallo-carbapenemases (VIM-27, IMP-1, NDM-1) in carbapenem-resistant Enterobacteriaceae (CRE) lysates.

SUBMITTER: Song A

PROVIDER: S-EPMC5849144 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Intramolecular substitution uncages fluorogenic probes for detection of metallo-carbapenemase-expressing bacteria.

Song Aiguo A Song Aiguo A Cheng Yunfeng Y Xie Jinghang J Banaei Niaz N Rao Jianghong J

Chemical science 20170921 11

This work reports a novel caging strategy for designing fluorogenic probes to detect the activity of β-lactamases. The caging strategy uses a thiophenyl linker connected to a fluorophore caged by a good leaving group-dinitrophenyl. The uncaging proceeds in two steps through the sulfa-releasing and subsequent intramolecular substitution. The length of the linker has been examined and optimized to maximize the rate of intramolecular reaction and thus the rate of fluorescence activation. Finally ba ...[more]

PMID: 29568429

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