RESUMO
Reported herein is a relebactam-derived fluorogenic reagent for covalent labeling of serine ß-lactamases (SBLs), which are the major causes of bacterial resistance to ß-lactam antibiotics. This highly selective imaging reagent generates over 300-fold stronger near-infrared fluorescence signals upon covalently bonding to SBLs, allowing wash-free visualization of live antimicrobial-resistant bacteria.
Assuntos
Marcadores de Afinidade/farmacologia , Compostos Azabicíclicos/farmacologia , Enterobacter cloacae/isolamento & purificação , Corantes Fluorescentes/farmacologia , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/química , Marcadores de Afinidade/síntese química , Marcadores de Afinidade/química , Compostos Azabicíclicos/síntese química , Compostos Azabicíclicos/química , Enterobacter cloacae/enzimologia , Fluoresceínas/síntese química , Fluoresceínas/química , Fluoresceínas/farmacologia , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Indóis/síntese química , Indóis/química , Indóis/farmacologia , Inibidores de beta-Lactamases/síntese química , Inibidores de beta-Lactamases/químicaRESUMO
Metallo-ß-lactamase is one of the major clinical threats because this ß-lactam-hydrolyzing enzyme confers significant resistance to most ß-lactam antibiotics, including carbapenems, among bacterial pathogens. Reported herein is a novel fluorogenic sensor for the specific detection of metallo-ß-lactamase activities. This carbapenem-based reagent exhibits excellent selectivity to metallo-ß-lactamase over other serine-ß-lactamases, including serine carbapenemases. The usefulness of this probe was further demonstrated in the rapid identification of metallo-ß-lactamase-expressing pathogenic bacteria.
Assuntos
Bactérias/enzimologia , Carbapenêmicos/química , Corantes Fluorescentes/química , beta-Lactamases/metabolismo , Carbapenêmicos/metabolismo , Escherichia coli/metabolismo , Hidrólise , Cinética , Limite de Detecção , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Espectrometria de Fluorescência , beta-Lactamases/química , beta-Lactamases/genéticaRESUMO
Reported herein is a fluorescence assay for the rapid screening of metallo-ß-lactamase (MBL) inhibitors. This assay employs a fluorogenic carbapenem CPC-1 as substrate and is compatible with all MBLs, including B1, B2 and B3 subclass MBLs. The efficiency of this assay was demonstrated by the rapid inhibition screening of a number of molecules against B2 MBL CphA and 2,3-dimercaprol was identified as a potent CphA inhibitor.
Assuntos
Carbapenêmicos/química , Fluorescência , Corantes Fluorescentes/química , Inibidores de beta-Lactamases/química , Carbapenêmicos/farmacologia , Relação Dose-Resposta a Droga , Corantes Fluorescentes/farmacologia , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismoRESUMO
The dissemination of antimicrobial resistance around the world is one of the biggest threats to global public health. The acquisition and expression of extended-spectrum ß-lactamases (ESBLs) in pathogenic bacterial are mainly responsible for bacterial resistance to third-generation cephalosporins. Reported herein is a ratiometric fluorescent probe for the detection of the activity of ESBLs. This imaging reagent adopts the core structure of cefotaxime as an enzymatic recognition moiety, and exhibits excellent selectivity to ESBLs over other ß-lactamases. The specific activation of this sensor by ESBLs can lead to over 2500-fold changes in the fluorescent ratio, which is independent of the concentration of the probe and environmental conditions. Further experiments have demonstrated that this ratiometric fluorescent probe can distinguish bacteria with extended-spectrum antibiotic resistance from a group of clinically important pathogens within a short period of time.