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1.
Antonie Van Leeuwenhoek ; 117(1): 78, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740670

RESUMO

Staphylococcus aureus is the etiologic agent of many nosocomial infections, and its biofilm is frequently isolated from medical devices. Moreover, the dissemination of multidrug-resistant (MDR) strains from this pathogen, such as methicillin-resistant S. aureus (MRSA) strains, is a worldwide public health issue. The inhibition of biofilm formation can be used as a strategy to weaken bacterial resistance. Taking that into account, we analysed the ability of marine sponge-associated bacteria to produce antibiofilm molecules, and we found that marine Priestia sp., isolated from marine sponge Scopalina sp. collected on the Brazilian coast, secretes proteins that impair biofilm development from S. aureus. Partially purified proteins (PPP) secreted after 24 hours of bacterial growth promoted a 92% biofilm mass reduction and 4.0 µg/dL was the minimum concentration to significantly inhibit biofilm formation. This reduction was visually confirmed by light microscopy and Scanning Electron Microscopy (SEM). Furthermore, biochemical assays showed that the antibiofilm activity of PPP was reduced by ethylenediaminetetraacetic acid (EDTA) and 1,10 phenanthroline (PHEN), while it was stimulated by zinc ions, suggesting an active metallopeptidase in PPP. This result agrees with mass spectrometry (MS) identification, which indicated the presence of a metallopeptidase from the M28 family. Additionally, whole-genome sequencing analysis of Priestia sp. shows that gene ywad, a metallopeptidase-encoding gene, was present. Therefore, the results presented herein indicate that PPP secreted by the marine Priestia sp. can be explored as a potential antibiofilm agent and help to treat chronic infections.


Assuntos
Antibacterianos , Proteínas de Bactérias , Biofilmes , Staphylococcus aureus , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Antibacterianos/farmacologia , Animais , Testes de Sensibilidade Microbiana , Brasil , Poríferos/microbiologia
2.
Bioinformatics ; 38(9): 2612-2614, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35188179

RESUMO

SUMMARY: Genome annotation pipelines traditionally exclude open reading frames (ORFs) shorter than 100 codons to avoid false identifications. However, studies have been showing that these may encode functional microproteins with meaningful biological roles. We developed µProteInS, a proteogenomics pipeline that combines genomics, transcriptomics and proteomics to identify novel microproteins in bacteria. Our pipeline employs a model to filter out low confidence spectra, to avoid the need for manually inspecting Mass Spectrometry data. It also overcomes the shortcomings of traditional approaches that usually exclude overlapping genes, leaderless transcripts and non-conserved sequences, characteristics that are common among small ORFs (smORFs) and hamper their identification. AVAILABILITY AND IMPLEMENTATION: µProteInS is implemented in Python 3.8 within an Ubuntu 20.04 environment. It is an open-source software distributed under the GNU General Public License v3, available as a command-line tool. It can be downloaded at https://github.com/Eduardo-vsouza/uproteins and either installed from source or executed as a Docker image. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Proteogenômica , Fases de Leitura Aberta , Proteogenômica/métodos , Software , Genômica/métodos , Bactérias/genética
3.
J Comput Aided Mol Des ; 37(3): 117-128, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36547753

RESUMO

Tuberculosis (TB) is one of the main causes of death from a single pathological agent, Mycobacterium tuberculosis (Mtb). In addition, the emergence of drug-resistant TB strains has exacerbated even further the treatment outcome of TB patients. It is thus needed the search for new therapeutic strategies to improve the current treatment and to circumvent the resistance mechanisms of Mtb. The shikimate kinase (SK) is the fifth enzyme of the shikimate pathway, which is essential for the survival of Mtb. The shikimate pathway is absent in humans, thereby indicating SK as an attractive target for the development of anti-TB drugs. In this work, a combination of in silico and in vitro techniques was used to identify potential inhibitors for SK from Mtb (MtSK). All compounds of our in-house database (Centro de Pesquisas em Biologia Molecular e Funcional, CPBMF) were submitted to in silico toxicity analysis to evaluate the risk of hepatotoxicity. Docking experiments were performed to identify the potential inhibitors of MtSK according to the predicted binding energy. In vitro inhibitory activity of MtSK-catalyzed chemical reaction at a single compound concentration was assessed. Minimum inhibitory concentration values for in vitro growth of pan-sensitive Mtb H37Rv strain were also determined. The mixed approach implemented in this work was able to identify five compounds that inhibit both MtSK and the in vitro growth of Mtb.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Simulação de Acoplamento Molecular , Antituberculosos/farmacologia , Antituberculosos/química , Tuberculose/tratamento farmacológico
4.
Molecules ; 27(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35458755

RESUMO

Tuberculosis remains a global health problem that affects millions of people around the world. Despite recent efforts in drug development, new alternatives are required. Herein, a series of 27 N-(4-(benzyloxy)benzyl)-4-aminoquinolines were synthesized and evaluated for their ability to inhibit the M. tuberculosis H37Rv strain. Two of these compounds exhibited minimal inhibitory concentrations (MICs) similar to the first-line drug isoniazid. In addition, these hit compounds were selective for the bacillus with no significant change in viability of Vero and HepG2 cells. Finally, chemical stability, permeability and metabolic stability were also evaluated. The obtained data show that the molecular hits can be optimized aiming at the development of drug candidates for tuberculosis treatment.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Aminoquinolinas/farmacologia , Antituberculosos/química , Humanos , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Tuberculose/tratamento farmacológico
5.
J Enzyme Inhib Med Chem ; 36(1): 847-855, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33752554

RESUMO

The dihydroneopterin aldolase (DHNA, EC 4.1.2.25) activity of FolB protein is required for the conversion of 7,8-dihydroneopterin (DHNP) to 6-hydroxymethyl-7,8-dihydropterin (HP) and glycolaldehyde (GA) in the folate pathway. FolB protein from Mycobacterium tuberculosis (MtFolB) is essential for bacilli survival and represents an important molecular target for drug development. S8-functionalized 8-mercaptoguanine derivatives were synthesised and evaluated for inhibitory activity against MtFolB. The compounds showed IC50 values in the submicromolar range. The inhibition mode and inhibition constants were determined for compounds that exhibited the strongest inhibition. Additionally, molecular docking analyses were performed to suggest enzyme-inhibitor interactions and ligand conformations. To the best of our knowledge, this study describes the first class of MtFolB inhibitors.


Assuntos
Aldeído Liases/antagonistas & inibidores , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Guanosina/análogos & derivados , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Tionucleosídeos/farmacologia , Aldeído Liases/genética , Aldeído Liases/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Guanosina/síntese química , Guanosina/química , Guanosina/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/enzimologia , Tionucleosídeos/síntese química , Tionucleosídeos/química
6.
Molecules ; 26(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668389

RESUMO

Tuberculosis (TB) has been described as a global health crisis since the second half of the 1990s. Mycobacterium tuberculosis (Mtb), the etiologic agent of TB in humans, is a very successful pathogen, being the main cause of death in the population among infectious agents. In 2019, it was estimated that around 10 million individuals were contaminated by this bacillus and about 1.2 million succumbed to the disease. In recent years, our research group has reported the design and synthesis of quinoline derivatives as drug candidates for the treatment of TB. These compounds have demonstrated potent and selective growth inhibition of drug-susceptible and drug-resistant Mtb strains. Herein, a new synthetic approach was established providing efficient and rapid access (15 min) to a series of 4-alkoxy-6-methoxy-2-methylquinolines using ultrasound energy. The new synthetic protocol provides a simple procedure utilizing an open vessel system that affords the target products at satisfactory yields (45-84%) and elevated purities (≥95%). The methodology allows the evaluation of a larger number of molecules in assays against the bacillus, facilitating the determination of the structure-activity relationship with a reduced environmental cost.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Quinaldinas/farmacologia , Ondas Ultrassônicas , Antituberculosos/síntese química , Antituberculosos/química , Testes de Sensibilidade Microbiana , Quinaldinas/síntese química , Quinaldinas/química
7.
Molecules ; 26(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500579

RESUMO

Tuberculosis has been described as a global health crisis since the 1990s, with an estimated 1.4 million deaths in the last year. Herein, a series of 20 1H-indoles were synthesized and evaluated as in vitro inhibitors of Mycobacterium tuberculosis (Mtb) growth. Furthermore, the top hit compounds were active against multidrug-resistant strains, without cross-resistance with first-line drugs. Exposing HepG2 and Vero cells to the molecules for 72 h showed that one of the evaluated structures was devoid of apparent toxicity. In addition, this 3-phenyl-1H-indole showed no genotoxicity signals. Finally, time-kill and pharmacodynamic model analyses demonstrated that this compound has bactericidal activity at concentrations close to the Minimum Inhibitory Concentration, coupled with a strong time-dependent behavior. To the best of our knowledge, this study describes the activity of 3-phenyl-1H-indole against Mtb for the first time.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Indóis/síntese química , Indóis/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana/métodos , Relação Estrutura-Atividade , Células Vero
8.
Invest New Drugs ; 38(6): 1653-1663, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32367200

RESUMO

Hepatocellular carcinoma (HCC) is the most prevalent type of tumor among primary liver tumors and is the second highest cause of cancer-related deaths worldwide. Current therapies are controversial, and more research is needed to identify effective treatments. A new synthetic compound, potassium 5-cyano-4-methyl-6-oxo-1,6-dihydropyridine-2-olate (CPBMF65), is a potent inhibitor of the human uridine phosphorylase-1 (hUP1) enzyme, which controls the cell concentration of uridine (Urd). Urd is a natural pyrimidine nucleoside involved in cellular processes, such as RNA synthesis. In addition, it is considered a promising biochemical modulator, as it may reduce the toxicity caused by chemotherapeutics without impairing its anti-tumor activity. Thus, the objective of this study is to evaluate the effects of CPBMF65 on the proliferation of the human hepatocellular carcinoma cell line (HepG2). Cell proliferation, cytotoxicity, apoptosis, senescence, autophagy, intracellular Urd levels, cell cycle arrest, and drug resistance were analyzed. Results demonstrate that, after incubation with CPBMF65, HepG2 cell proliferation decreased, mainly through cell cycle arrest and senescence, increasing the levels of intracellular Urd and maintaining cell proliferation reduced during chronic treatment. In conclusion, results show, for the first time, the ability of a hUP1 inhibitor (CPBMF65) to reduce HepG2 cell proliferation through cell cycle arrest and senescence.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Piridinas/farmacologia , Uridina Fosforilase/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Células Hep G2 , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Uridina/farmacologia
9.
Microb Pathog ; 119: 60-64, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29608932

RESUMO

Purine nucleoside phosphorylase from Mycobacterium tuberculosis (MtPNP), encoded by deoD gene (Rv3307), is an enzyme from the purine salvage pathway, which has been widely studied as a molecular target for the development of inhibitors with potential antimycobacterial activity. However, the role of MtPNP in tuberculosis pathogenesis and dormancy is still unknown. The present work aims to construct a deoD knockout strain from M. tuberculosis, to evaluate the role of MtPNP in the growth of M. tuberculosis under oxygenated condition and in a dormancy model, and to assess whether deoD gene is important for M. tuberculosis invasion and growth in macrophages. The construction of a knockout strain for deoD gene was confirmed at DNA level by PCR and protein level by Western blot and LC-MS/MS. The deoD gene is not required for M. tuberculosis growth and survival under oxygenated and hypoxic conditions. The disruption of deoD gene did not affect mycobacterial ability to invade and grow in RAW 264.7 cells under the experimental conditions employed here.


Assuntos
Macrófagos/microbiologia , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/genética , Purina-Núcleosídeo Fosforilase/genética , Purina-Núcleosídeo Fosforilase/fisiologia , Animais , Sequência de Bases , Cromatografia Líquida , DNA Bacteriano/genética , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes Bacterianos/genética , Camundongos , Mycobacterium tuberculosis/patogenicidade , Oxigênio/metabolismo , Células RAW 264.7 , Espectrometria de Massas em Tandem , Tuberculose/microbiologia
10.
Regul Toxicol Pharmacol ; 90: 78-86, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28838610

RESUMO

IQG-607 is an anti-tuberculosis drug candidate, with a promising safety and efficacy profile in models of tuberculosis infection both in vitro and in vivo. Here, we evaluated the safety and the possible toxic effects of IQG-607 after acute and 90-day repeated administrations in minipigs. Single oral administration of IQG-607 (220 mg/kg) to female and male minipigs did not result in any morbidity or mortality. No gross lesions were observed in the minipigs at necropsy. Repeated administration of IQG 607 (65, 30, or 15 mg/kg), given orally, for 90 days, in both male and female animals did not cause any mortality and no significant body mass alteration. Diarrhea and alopecia were the clinical signs observed in animals dosed with IQG-607 for 90 days. Long-term treatment with IQG-607 did not induce evident alterations of blood cell counts or any hematological parameters. Importantly, the repeated schedule of administration of IQG-607 resulted in increased cholesterol levels, increased glucose levels, decrease in the globulin levels, and increased creatinine levels over the time. Most necropsy and histopathological alterations of the organs from IQG-607-treated groups were also observed for the untreated group. In addition, pharmacokinetic parameters were evaluated. IQG-607 represents a potential candidate molecule for anti-tuberculosis drug development programs. Its promising in vivo activity and mild to moderate toxic events detected in this study suggest that IQG-607 represents a candidate for clinical development.


Assuntos
Alopecia/induzido quimicamente , Antituberculosos/toxicidade , Diarreia/induzido quimicamente , Compostos Ferrosos/toxicidade , Isoniazida/análogos & derivados , Administração Oral , Animais , Antituberculosos/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Feminino , Compostos Ferrosos/farmacocinética , Isoniazida/farmacocinética , Isoniazida/toxicidade , Masculino , Modelos Animais , Suínos , Porco Miniatura , Fatores de Tempo , Testes de Toxicidade/métodos
11.
Mem Inst Oswaldo Cruz ; 112(3): 203-208, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28225907

RESUMO

BACKGROUND: Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis. The better understanding of important metabolic pathways from M. tuberculosis can contribute to the development of novel therapeutic and prophylactic strategies to combat TB. Nucleoside hydrolase (MtIAGU-NH), encoded by iunH gene (Rv3393), is an enzyme from purine salvage pathway in M. tuberculosis. MtIAGU-NH accepts inosine, adenosine, guanosine, and uridine as substrates, which may point to a pivotal metabolic role. OBJECTIVES: Our aim was to construct a M. tuberculosis knockout strain for iunH gene, to evaluate in vitro growth and the effect of iunH deletion in M. tuberculosis in non-activated and activated macrophages models of infection. METHODS: A M. tuberculosis knockout strain for iunH gene was obtained by allelic replacement, using pPR27xylE plasmid. The complemented strain was constructed by the transformation of the knockout strain with pNIP40::iunH. MtIAGU-NH expression was analysed by Western blot and LC-MS/MS. In vitro growth was evaluated in Sauton's medium. Bacterial load of non-activated and interferon-γ activated RAW 264.7 cells infected with knockout strain was compared with wild-type and complemented strains. FINDINGS: Western blot and LC-MS/MS validated iunH deletion at protein level. The iunH knockout led to a delay in M. tuberculosis growth kinetics in Sauton's medium during log phase, but did not affect bases and nucleosides pool in vitro. No significant difference in bacterial load of knockout strain was observed when compared with both wild-type and complemented strains after infection of non-activated and interferon-γ activated RAW 264.7 cells. MAIN CONCLUSION: The disruption of iunH gene does not influence M. tuberculosis growth in both non-activated and activated RAW 264.7 cells, which show that iunH gene is not important for macrophage invasion and virulence. Our results indicated that MtIAGU-NH is not a target for drug development.


Assuntos
Técnicas de Inativação de Genes , Genes Bacterianos , Mycobacterium tuberculosis/genética , N-Glicosil Hidrolases/genética , Humanos , Macrófagos/microbiologia , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/crescimento & desenvolvimento
12.
Mem Inst Oswaldo Cruz ; 112(11): 785-789, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29091140

RESUMO

Cytidine deaminase (MtCDA), encoded by cdd gene (Rv3315c), is the only enzyme identified in nucleotide biosynthesis pathway of Mycobacterium tuberculosis that is able to recycle cytidine and deoxycytidine. An M. tuberculosis knockout strain for cdd gene was obtained by allelic replacement. Evaluation of mRNA expression validated cdd deletion and showed the absence of polar effect. MudPIT LC-MS/MS data indicated thymidine phosphorylase expression was decreased in knockout and complemented strains. The cdd disruption does not affect M. tuberculosis growth both in Mid- dlebrook 7H9 and in RAW 264.7 cells, which indicates that cdd is not important for macrophage invasion and virulence.


Assuntos
Citidina Desaminase/genética , Desoxicitidina/genética , Macrófagos/microbiologia , Mycobacterium tuberculosis/patogenicidade , Citidina Desaminase/biossíntese , Desoxicitidina/biossíntese , Técnicas de Inativação de Genes , Humanos , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Fatores de Tempo
13.
Biochimie ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642825

RESUMO

Astrocytes are glial cells that play key roles in neuroinflammation, which is a common feature in diabetic encephalopathy and aging process. Metformin is an antidiabetic compound that shows neuroprotective properties, including in inflammatory models, but astroglial signaling pathways involved are still poorly known. Interferons α/ß are cytokines that participate in antiviral responses and the lack of their signaling increases susceptible to viral infections. Here, we investigated the effects of metformin on astrocytes from hypothalamus, a crucial brain region related to inflammatory processes. Astrocyte cultures were derived from interferon α/ß receptor knockout (IFNα/ßR-/-) and wild-type (WT) mice. Metformin did not change the expression of glial fibrillary acidic protein but caused an anti-inflammatory effect by decreasing pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1ß), as well as increasing gene expression of anti-inflammatory proteins interleukin-10 and Nrf2 (nuclear factor erythroid derived 2 like 2). However, nuclear factor κB p65 and cyclooxygenase 2 were downregulated in WT astrocytes and upregulated in IFNα/ßR-/- astrocytes. AMP-activated protein kinase (AMPK), a molecular target of metformin, was upregulated only in WT astrocytes, while sirtuin 1 increased in both mice models. The expression of inducible nitric oxide synthase was decreased in WT astrocytes and heme oxygenase 1 was increased in IFNα/ßR-/- astrocytes. Although loss of IFNα/ßR-mediated signaling affects some effects of metformin, our results support beneficial roles of this drug in hypothalamic astrocytes. Moreover, paradoxical response of metformin may involve AMPK. Thus, metformin can mediate glioprotection due its effects on age-related disorders in non-diabetic and diabetic encephalopathy individuals.

14.
ACS Med Chem Lett ; 15(4): 493-500, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38628799

RESUMO

Utilizing a scaffold-hopping strategy from the drug candidate telacebec, a novel series of 2-(quinolin-4-yloxy)acetamides was synthesized and evaluated as inhibitors of Mycobacterium tuberculosis (Mtb) growth. These compounds demonstrated potent activity against drug-sensitive and multidrug-resistant strains (MIC ≤ 0.02 µM). Leading compounds were evaluated against a known qcrB resistant strain (T313A), and their loss in activity suggested that the cytochrome bc1 complex is the likely target. Additionally, these structures showed high selectivity regarding mammalian cells (selectivity index > 500) and stability across different aqueous media. Furthermore, some of the synthesized quinolines demonstrated aqueous solubility values that exceeded those of telacebec, while maintaining low rates of metabolism. Finally, a selected compound prevented Mtb growth by more than 1.7 log10 colony forming units in a macrophage model of tuberculosis (TB) infection. These findings validate the proposed design and introduce new 2-(quinolin-4-yloxy)acetamides with potential for development in TB drug discovery campaigns.

15.
Arch Biochem Biophys ; 538(2): 80-94, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23988349

RESUMO

Tuberculosis (TB) is a major global health threat. There is a need for the development of more efficient drugs for the sterilization of the disease's causative agent, Mycobacterium tuberculosis (MTB). A more comprehensive understanding of the bacilli's nucleotide metabolic pathways could aid in the development of new anti-mycobacterial drugs. Here we describe expression and purification of recombinant iunH-encoded nucleoside hydrolase from MTB (MtIAGU-NH). Glutaraldehyde cross-linking results indicate that MtIAGU-NH predominates as a monomer, presenting varied oligomeric states depending upon binding of ligands. Steady-state kinetics results show that MtIAGU-NH has broad substrate specificity, accepting inosine, adenosine, guanosine, and uridine as substrates. Inosine and adenosine displayed positive homotropic cooperativity kinetics, whereas guanosine and uridine displayed hyperbolic saturation curves. Measurements of kinetics of ribose binding to MtIAGU-NH by fluorescence spectroscopy suggest two pre-existing forms of enzyme prior to ligand association. The intracellular concentrations of inosine, uridine, hypoxanthine, and uracil were determined and thermodynamic parameters estimated. Thermodynamic activation parameters (Ea, ΔG(#), ΔS(#), ΔH(#)) for MtIAGU-NH-catalyzed chemical reaction are presented. Results from mass spectrometry, isothermal titration calorimetry (ITC), pH-rate profile experiment, multiple sequence alignment, and molecular docking experiments are also presented. These data should contribute to our understanding of the biological role played by MtIAGU-NH.


Assuntos
Mycobacterium tuberculosis/enzimologia , N-Glicosil Hidrolases/química , N-Glicosil Hidrolases/metabolismo , Tuberculose/microbiologia , Sequência de Aminoácidos , Cálcio/análise , Clonagem Molecular , Humanos , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , N-Glicosil Hidrolases/genética , N-Glicosil Hidrolases/isolamento & purificação , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Especificidade por Substrato , Termodinâmica
16.
Int Immunopharmacol ; 117: 109954, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36870284

RESUMO

We analyzed the ability of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) itself and SARS-CoV-2-IgG immune complexes to trigger human monocyte necroptosis. SARS-CoV-2 was able to induce monocyte necroptosis dependently of MLKL activation. Necroptosis-associated proteins (RIPK1, RIPK3 and MLKL) were involved in SARS-CoV-2N1 gene expression in monocytes. SARS-CoV-2 immune complexes promoted monocyte necroptosis in a RIPK3- and MLKL-dependent manner, and Syk tyrosine kinase was necessary for SARS-CoV-2 immune complex-induced monocyte necroptosis, indicating the involvement of Fcγ receptors on necroptosis. Finally, we provide evidence that elevated LDH levels as a marker of lytic cell death are associated with COVID-19 pathogenesis.


Assuntos
Complexo Antígeno-Anticorpo , COVID-19 , Humanos , Complexo Antígeno-Anticorpo/metabolismo , SARS-CoV-2 , Proteínas Quinases/metabolismo , Monócitos , Necroptose , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
17.
Eur J Med Chem ; 245(Pt 1): 114908, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36435016

RESUMO

Herein a series of 4-aminoquinolines were synthesized in an attempt to optimize and study the structural features related to LABIO-17 biological activity, a Mycobacterium tuberculosis NADH-dependent enoyl-acyl carrier protein reductase (MtInhA) inhibitor previously identified by a virtual-ligand-screening approach. Structure-activity relationships led to novel submicromolar inhibitors of MtInhA and potent antitubercular agents. The lead compound is 87-fold more potent as enzymatic inhibitors and 32-fold more potent against M. tuberculosis H37Rv strain in comparison with LABIO-17. These molecules were also active against multidrug-resistant strains, devoid of apparent toxicity to mammalian cells and showed favorable in vitro ADME profiles. Additionally, these compounds were active in an intracellular model of tuberculosis (TB) infection, showed no genotoxicity signals, satisfactory absorption parameters and absence of in vivo acute toxicity. Finally, treatment with selected 4-aminoquinoline for two weeks produced bacteriostatic effect in a murine model of TB. Taken together, these findings indicate that this chemical class may furnish candidates for the future development of drug-sensitive and drug-resistant tuberculosis treatments.


Assuntos
Aminoquinolinas , Antituberculosos , Inibidores Enzimáticos , Mycobacterium tuberculosis , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+) , Animais , Camundongos , Aminoquinolinas/síntese química , Aminoquinolinas/farmacologia , Aminoquinolinas/uso terapêutico , Antituberculosos/síntese química , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+)/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Tuberculose/tratamento farmacológico , Modelos Animais de Doenças
18.
J Biol Inorg Chem ; 17(2): 275-83, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21952749

RESUMO

For over a decade, tuberculosis (TB) has been the leading cause of death among infectious diseases. Since the 1950s, isoniazid has been used as a front-line drug in the treatment of TB; however, resistant TB strains have limited its use. The major route of isoniazid resistance relies on KatG enzyme disruption, which does not promote an electron transfer reaction. Here, we investigated the reactivity of isoniazid metal complexes as prototypes for novel self-activating metallodrugs against TB with the aim to overcome resistance. Reactivity studies were conducted with hydrogen peroxide, hexacyanoferrate(III), and aquopentacyanoferrate(III). The latter species showed a preference for the inner-sphere electron transfer reaction pathway. Additionally, electron transfer reaction performed with either free isoniazid or (isoniazid)pentacyanoferrate(II) complex resulted in similar oxidized isoniazid derivatives as observed when the KatG enzyme was used. However, upon metal coordination, a significant enhancement in the formation of isonicotinic acid was observed compared with that of isonicotinamide. These results suggest that the pathway of a carbonyl-centered radical might be favored upon coordination to the Fe(II) owing to the π-back-bonding effect promoted by this metal center; therefore, the isoniazid metal complex could serve as a potential metallodrug. Enzymatic inhibition assays conducted with InhA showed that the cyanoferrate moiety is not the major player involved in this inhibition but the presence of isoniazid is required in this process. Other isoniazid metal complexes, [Ru(CN)(5)(izd)](3-) and [Ru(NH(3))(5)(izd)](2+) (where izd is isoniazid), were also unable to inhibit InhA, supporting our proposed self-activating mechanism of action. We propose that isoniazid reactivity can be rationally modulated by metal coordination chemistry, leading to the development of novel anti-TB metallodrugs.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Desenho de Fármacos , Isoniazida/química , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Oxirredutases/antagonistas & inibidores , Farmacorresistência Bacteriana , Compostos Férricos/química , Humanos , Mycobacterium tuberculosis/enzimologia , Oxirredução , Tuberculose/tratamento farmacológico , Tuberculose/enzimologia
19.
J Mol Model ; 28(6): 140, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35534695

RESUMO

Flexibility and function are related properties in the study of protein dynamics. Flexibility reflects in the conformational potential of proteins and thus in their functionalities. The presence of interactions between protein-ligands and protein-protein complexes, substrates, and environmental changes can alter protein plasticity, acting from the rearrangement of the side chains of amino acids to the folding/unfolding of large structural motifs. To evaluate the effects of the flexibility in protein systems, we defined the enzyme 2-trans-enoyl-ACP (CoA) reductase from Mycobacterium tuberculosis, or MtInhA, as our target system. MtInhA is biologically active as a tetramer in solution; however, computational studies commonly use the monomer justifying the independence of its active sites due to their distances. However, differences in flexibility between tertiary and quaternary structures could present impact on the size of the active site, influencing the drug discovery process. In this study, we investigated the influence of flexibility restrictions in A- and B-loops of the MtInhA in order to suggest a monomeric structure that describes the conformational behavior of the tetrameric system. Overall, we observed that simulations where restrictions were applied to the A- and B-loops present a more similar behavior to the native structure when compared to unrestricted simulations. Therefore, our work presents a monomeric model of MtInhA, which has conformational characteristics of the biologically active structure. Thus, the data obtained in this work can be applied to the MtInhA system for the generation of more reliable flexible models for molecular docking experiments, and also for the performance of longer simulations by molecular dynamics and with a lower computational cost.


Assuntos
Simulação de Dinâmica Molecular , Mycobacterium tuberculosis , Proteínas de Bactérias/química , Simulação de Acoplamento Molecular , Oxirredutases/metabolismo
20.
Int J Biol Macromol ; 199: 307-317, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35007635

RESUMO

This study aimed to develop single-step purification and immobilization processes on cellulosic supports of ß-galactosidase from Kluyveromyces sp. combined with the Cellulose-Binding Domain (CBD) tag. After 15 min of immobilization, with an enzymatic load of 150 U/gsupport, expressed activity values reached 106.88 (microcrystalline cellulose), 115.03 (alkaline nanocellulose), and 108.47 IU/g (acid nanocellulose). The derivatives produced were less sensitive to the presence of galactose in comparison with the soluble purified enzyme. Among the cations assessed (Na+, K+, Mg2+, and Ca2+), magnesium provided the highest increase in the enzymatic activity of ß-galactosidases immobilized on cellulosic supports. Supports and derivatives showed no cytotoxic effect on the investigated cell cultures (HepG2 and Vero). Derivatives showed high operational stability in the hydrolysis of milk lactose and retained from 53 to 64% of their hydrolysis capacity after 40 reuse cycles. This study obtained biocatalyzers with promising characteristics for application in the food industry. Biocatalyzers were obtained through a low-cost one-step sustainable bioprocess of purification and immobilization of a ß-galactosidase on cellulose via CBD.


Assuntos
Enzimas Imobilizadas , Lactose , Celulose , Estabilidade Enzimática , Enzimas Imobilizadas/química , Hidrólise , Lactose/química , beta-Galactosidase/química
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