RESUMEN
We report here the optimization of an HldE kinase inhibitor to low nanomolar potency, which resulted in the identification of the first reported compounds active on selected E. coli strains. One of the most interesting candidates, compound 86, was shown to inhibit specifically bacterial LPS heptosylation on efflux pump deleted E. coli strains. This compound did not interfere with E. coli bacterial growth (MIC > 32 µg/mL) but sensitized this pathogen to hydrophobic antibiotics like macrolides normally inactive on Gram-negative bacteria. In addition, 86 could sensitize E. coli to serum complement killing. These results demonstrate that HldE kinase is a suitable target for drug discovery. They also pave the way toward novel possibilities of treating or preventing bloodstream infections caused by pathogenic Gram negative bacteria by inhibiting specific virulence factors.
Asunto(s)
Antibacterianos/síntesis química , Benzotiazoles/síntesis química , Escherichia coli/efectos de los fármacos , Complejos Multienzimáticos/antagonistas & inhibidores , Nucleotidiltransferasas/antagonistas & inhibidores , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Triazinas/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Benzotiazoles/química , Benzotiazoles/farmacología , Escherichia coli/patogenicidad , Lipopolisacáridos/farmacología , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad , Triazinas/química , Triazinas/farmacología , Virulencia/efectos de los fármacosRESUMEN
As an essential constituent of the outer membrane of Gram-negative bacteria, lipopolysaccharide contributes significantly to virulence and antibiotic resistance. The lipopolysaccharide biosynthetic pathway therefore serves as a promising therapeutic target for antivirulence drugs and antibiotic adjuvants. Here we report the structural-functional studies of D-glycero-ß-D-manno-heptose 7-phosphate kinase (HldA), an absolutely conserved enzyme in this pathway, from Burkholderia cenocepacia. HldA is structurally similar to members of the PfkB carbohydrate kinase family and appears to catalyze heptose phosphorylation via an in-line mechanism mediated mainly by a conserved aspartate, Asp270. Moreover, we report the structures of HldA in complex with two potent inhibitors in which both inhibitors adopt a folded conformation and occupy the nucleotide-binding sites. Together, these results provide important insight into the mechanism of HldA-catalyzed heptose phosphorylation and necessary information for further development of HldA inhibitors.
Asunto(s)
Antibacterianos/química , Proteínas Bacterianas/química , Burkholderia cenocepacia/enzimología , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Proteínas Bacterianas/genética , Burkholderia cenocepacia/genética , Cristalografía por Rayos X , Modelos Moleculares , Mutación , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Conformación Proteica , Relación Estructura-Actividad , VirulenciaRESUMEN
In this paper, we present some elements of our optimization program to decouple triclosan's specific FabI effect from its nonspecific cytotoxic component. The implementation of this strategy delivered highly specific, potent, and nonbiocidal new FabI inhibitors. We also disclose some preclinical data of one of their representatives, 83, a novel antibacterial compound active against resistant staphylococci and some clinically relevant Gram negative bacteria that is currently undergoing clinical trials.
Asunto(s)
Antiinfecciosos Locales/farmacología , Benzamidas/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Enoil-ACP Reductasa (NADH)/antagonistas & inhibidores , Bacterias Gramnegativas/efectos de los fármacos , Éteres Fenílicos/farmacología , Triclosán/farmacología , Animales , Antiinfecciosos Locales/síntesis química , Benzamidas/síntesis química , Células Cultivadas , Perros , Evaluación Preclínica de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Éteres Fenílicos/síntesis química , Ratas , Relación Estructura-Actividad , Triclosán/síntesis químicaRESUMEN
The synthesis and SAR studies of a series of structurally novel small molecule inhibitors of PDE7 are discussed. The best compounds from the series displayed low nanomolar inhibitory activity and are selective versus PDE4.
Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Isoenzimas/antagonistas & inhibidores , Inhibidores de Fosfodiesterasa/síntesis química , Inhibidores de Fosfodiesterasa/farmacología , Tiadiazoles/síntesis química , Tiadiazoles/farmacología , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Línea Celular , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4 , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 7 , Humanos , Isoenzimas/metabolismo , Inhibidores de Fosfodiesterasa/química , Relación Estructura-Actividad , Tiadiazoles/químicaRESUMEN
The synthesis and optimization of pharmacokinetic parameters of structurally novel small PDE7 inhibitors is discussed.
Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Isoenzimas/antagonistas & inhibidores , Inhibidores de Fosfodiesterasa/farmacocinética , Tiadiazoles/farmacocinética , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Administración Oral , Animales , Disponibilidad Biológica , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 7 , Isoenzimas/metabolismo , Inhibidores de Fosfodiesterasa/síntesis química , Inhibidores de Fosfodiesterasa/química , Ratas , Estereoisomerismo , Relación Estructura-Actividad , Tiadiazoles/síntesis química , Tiadiazoles/químicaRESUMEN
The synthesis and SAR studies of spiroquinazolinones as novel PDE7 inhibitors are discussed. The best compounds from the series displayed nanomolar inhibitory affinity and were selective versus other PDE isoenzymes.
Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Isoenzimas/antagonistas & inhibidores , Inhibidores de Fosfodiesterasa/síntesis química , Quinazolinas/síntesis química , Compuestos de Espiro/síntesis química , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Línea Celular , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 7 , Evaluación Preclínica de Medicamentos , Humanos , Isoenzimas/metabolismo , Inhibidores de Fosfodiesterasa/química , Inhibidores de Fosfodiesterasa/farmacología , Quinazolinas/química , Quinazolinas/farmacología , Solubilidad , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Relación Estructura-ActividadRESUMEN
The optimization of 5,8-disubstituted spirocyclohexane-quinazolinones into potent, selective, soluble PDE7 inhibitors with acceptable in vivo pharmacokinetic parameters is presented.