RESUMO
There is a great need for identification and development of new anti-tuberculosis drugs with novel targets. Recent drug-discovery efforts typically focus on identifying inhibitors but not activators that perturb metabolic enzymes' functions as a means to kill Mycobacterium tuberculosis (Mtb). Here, we describe a class of quinoline compounds, Z0933/Z0930, which kill Mtb by acting as activators of glutamate kinase (GK), a previously untargeted enzyme catalyzing the first step of proline biosynthesis. We further show that Z0933/Z0930 augment proline production and induce Mtb killing via proline-derived redox imbalance and production of reactive oxygen species. This work highlights the effectiveness of gain-of-function probes against Mtb and provides a framework for the discovery of next-generation allosteric activators of GK.
Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Fosfotransferases (Aceptor do Grupo Carboxila)/metabolismo , Quinolinas/farmacologia , Animais , Antituberculosos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Cinética , Macrófagos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/enzimologia , Fosfotransferases (Aceptor do Grupo Carboxila)/genética , Estabilidade Proteica , Quinolinas/química , Células RAW 264.7 , Relação Estrutura-AtividadeRESUMO
We expressed the wild-type rplC and mutated rplC (Cys154Arg) genes, respectively, in Mycobacterium tuberculosis H37Ra and H37Rv in an attempt to delineate the role of rplC (Cys154Arg) regarding oxazolidinone resistance. An increase of the MICs of linezolid (LZD) and sutezolid (PNU-100480, PNU) against the recombinant mycobacteria with overexpressed rplC mutation (Cys154Arg) was found, suggesting the rplC gene is a determinant of bacillary susceptibilities to LZD and PNU.
Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/metabolismo , Oxazolidinonas/farmacologia , Proteínas Ribossômicas/metabolismo , Linezolida/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Proteína Ribossômica L3 , Proteínas Ribossômicas/genéticaRESUMO
The combination of trimethoprim (TMP) and sulfamethoxazole (SMX) has been shown to be active against Mycobacterium tuberculosis (Mtb) in clinical tuberculosis (TB) treatment. However, the mechanism of action of TMP-SMX against Mtb is still unknown. To unravel this, we have studied the effect of TMP and SMX by deleting the folP2 gene in Mycobacterium smegmatis (Msm), and overexpressing the Mtb and Msm folP1/2 genes in Msm. Knocking out of the folP2 gene in Msm reduced the minimum inhibitory concentration of SMX 8-fold compared with wild type. Overexpression of the folP1 genes from Mtb and Msm increased the MICs by 4- and 2-fold in Msm for SMX and TMP, respectively. We show a strong correlation between the expression of folP1 and folP2 genes and TMP-SMX resistance in mycobacteria. This suggests that a combination of FolP2 inhibitor and SMX could be used for TB treatment with a better outcome.