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1.
Biochim Biophys Acta Gen Subj ; 1867(1): 130265, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36280021

RESUMO

BACKGROUND: Some cationic and amphiphilic α-helical segments of proteins adsorb to prokaryotic membranes when synthesized as individual polypeptide sequences, resulting in broad and potent antimicrobial activity. However, amphiphilicity, a determinant physicochemical property for peptide-membrane interactions, can also be observed in some ß-sheets. METHODS: The software Kamal was used to scan the human reference proteome for short (7-11 amino acid residues) cationic and amphiphilic protein segments with the characteristic periodicity of ß-sheets. Some of the uncovered peptides were chemically synthesized, and antimicrobial assays were conducted. Biophysical techniques were used to probe the molecular interaction of one peptide with phospholipid vesicles, lipopolysaccharides (LPS) and the bacterium Escherichia coli. RESULTS: Thousands of compatible segments were found in human proteins, five were synthesized, and three presented antimicrobial activity in the micromolar range. Hs10, a nonapeptide fragment of the Complement C3 protein, could inhibit only the growth of tested Gram-negative microorganisms, presenting also little cytotoxicity to human fibroblasts. Hs10 interacted with LPS while transitioning from an unstructured segment to a ß-sheet and increased the hydrodynamic radius of LPS particles. This peptide also promoted morphological alterations in E. coli cells. CONCLUSIONS: Data presented herein introduce yet another molecular template to probe proteins in search for encrypted membrane-active segments and demonstrates that, using this approach, short peptides with low cytotoxicity and high selectivity to prokaryotic cells might be obtained. GENERAL SIGNIFICANCE: This work widens the biotechnological potential of the human proteome as a source of antimicrobial peptides with application in human health.


Assuntos
Anti-Infecciosos , Escherichia coli , Humanos , Escherichia coli/metabolismo , Peptídeos Antimicrobianos , Lipopolissacarídeos/farmacologia , Proteoma , Bactérias Gram-Negativas/metabolismo , Peptídeos/química
2.
J Pept Sci ; 28(5): e3382, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34859535

RESUMO

Disintegrins comprise a family of small proteins that bind to and alter the physiological function of integrins, especially integrins that mediate platelet aggregation in blood. Here, we report a lysine-glycine-aspartic acid (KGD) disintegrin-like motif present in a 15-amino acid residue peptide identified in a cDNA library of the amphibian Hypsiboas punctatus skin. The original peptide sequence was used as a template from which five new analogs were designed, chemically synthesized by solid phase, and tested for disintegrin activity and tridimensional structural studies using NMR spectroscopy. The original amphibian peptide had no effect on integrin-mediated responses. Nevertheless, derived peptide analogs inhibited integrin-mediated platelet function, including platelet spreading on fibrinogen.


Assuntos
Desintegrinas , Peptídeos , Anfíbios/genética , Anfíbios/metabolismo , Animais , DNA Complementar/genética , Desintegrinas/química , Desintegrinas/genética , Desintegrinas/farmacologia , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Agregação Plaquetária/fisiologia
3.
Macromol Mater Eng ; 306(1)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34539237

RESUMO

In order to better understand the relationship between Flagelliform (Flag) spider silk molecular structural organization and the mechanisms of fiber assembly, it was designed and produced the Nephilengys cruentata Flag spidroin analogue rNcFlag2222. The recombinant proteins are composed by the elastic repetitive glycine-rich motifs (GPGGX/GGX) and the spacer region, rich in hydrophilic charged amino acids, present at the native silk spidroin. Using different approaches for nanomolecular protein analysis, the structural data of rNcFlag2222 recombinant proteins were compared in its fibrillar and in its fully solvated states. Based on the results was possible to identify the molecular structural dynamics of NcFlag2222 prior to and after fiber formation. Overal rNcFlag2222 shows a mixture of semiflexible and rigid conformations, characterized mostly by the presence of PPII, ß-turn and ß-sheet. These results agree with previous studies and bring insights about the molecular mechanisms that might driven Flag silk fibers assembly and elastomeric behavior.

4.
Ecancermedicalscience ; 15: 1195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33889204

RESUMO

Oesophageal cancer is among the ten most common types of cancer worldwide. More than 80% of the cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of oesophageal and oesophagogastric junction (OGJ) carcinomas. The Brazilian Group of Gastrointestinal Tumours invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy (including checkpoint inhibitors) and follow-up, which was followed by presentation, discussion and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of oesophageal and OGJ carcinomas in several scenarios and clinical settings.

5.
Clin Cancer Res ; 27(1): 78-86, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873572

RESUMO

PURPOSE: Patients with advanced renal cell carcinoma with sarcomatoid features (sRCC) have poor prognoses and suboptimal outcomes with targeted therapy. This post hoc analysis of the phase III CheckMate 214 trial analyzed the efficacy of nivolumab plus ipilimumab (NIVO+IPI) versus sunitinib in patients with sRCC. PATIENTS AND METHODS: Patients with sRCC were identified via independent central pathology review of archival tumor tissue or histologic classification per local pathology report. Patients were randomized 1:1 to receive nivolumab (3 mg/kg) plus ipilimumab (1 mg/kg) every 3 weeks (four doses) then nivolumab 3 mg/kg every 2 weeks, or sunitinib 50 mg orally every day (4 weeks; 6-week cycles). Outcomes in patients with sRCC were not prespecified. Endpoints in patients with sRCC and International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor-risk disease included overall survival (OS), progression-free survival (PFS) per independent radiology review, and objective response rate (ORR) per RECIST v1.1. Safety outcomes used descriptive statistics. RESULTS: Of 1,096 randomized patients in CheckMate 214, 139 patients with sRCC and intermediate/poor-risk disease and six with favorable-risk disease were identified. With 42 months' minimum follow-up in patients with sRCC and intermediate/poor-risk disease, median OS [95% confidence interval (CI)] favored NIVO+IPI [not reached (NR) (25.2-not estimable [NE]); n = 74] versus sunitinib [14.2 months (9.3-22.9); n = 65; HR, 0.45 (95% CI, 0.3-0.7; P = 0.0004)]; PFS benefits with NIVO+IPI were similarly observed [median 26.5 vs. 5.1 months; HR, 0.54 (95% CI, 0.33-0.86; P = 0.0093)]. Confirmed ORR was 60.8% with NIVO+IPI versus 23.1% with sunitinib, with complete response rates of 18.9% versus 3.1%, respectively. No new safety signals emerged. CONCLUSIONS: NIVO+IPI showed unprecedented long-term survival, response, and complete response benefits versus sunitinib in previously untreated patients with sRCC and intermediate/poor-risk disease, supporting the use of first-line NIVO+IPI for this population.See related commentary by Hwang et al., p. 5.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Via de Sinalização Hippo , Humanos , Imunoterapia , Ipilimumab/efeitos adversos , Neoplasias Renais/tratamento farmacológico , Nivolumabe/efeitos adversos , Proteínas Serina-Treonina Quinases , Sunitinibe/uso terapêutico
6.
Ecancermedicalscience ; 14: 1126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33209117

RESUMO

Gastric cancer is among the ten most common types of cancer worldwide. Most cases and deaths related to the disease occur in developing countries. Local socio-economic, epidemiologic and healthcare particularities led us to create a Brazilian guideline for the management of gastric carcinomas. The Brazilian Group of Gastrointestinal Tumors (GTG) invited 50 physicians with different backgrounds, including radiology, pathology, endoscopy, nuclear medicine, genetics, oncological surgery, radiotherapy and clinical oncology, to collaborate. This document was prepared based on an extensive review of topics related to heredity, diagnosis, staging, pathology, endoscopy, surgery, radiation, systemic therapy and follow-up, which was followed by presentation, discussion, and voting by the panel members. It provides updated evidence-based recommendations to guide clinical management of gastric carcinomas in several scenarios and clinical settings.

7.
Commun Biol ; 3(1): 255, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444777

RESUMO

Recently, new serine integrases have been identified, increasing the possibility of scaling up genomic modulation tools. Here, we describe the use of unidirectional genetic switches to evaluate the functionality of six serine integrases in different eukaryotic systems: the HEK 293T cell lineage, bovine fibroblasts and plant protoplasts. Moreover, integrase activity was also tested in human cell types of therapeutic interest: peripheral blood mononuclear cells (PBMCs), neural stem cells (NSCs) and undifferentiated embryonic stem (ES) cells. The switches were composed of plasmids designed to flip two different genetic parts driven by serine integrases. Cell-based assays were evaluated by measurement of EGFP fluorescence and by molecular analysis of attL/attR sites formation after integrase functionality. Our results demonstrate that all the integrases were capable of inverting the targeted DNA sequences, exhibiting distinct performances based on the cell type or the switchable genetic sequence. These results should support the development of tunable genetic circuits to regulate eukaryotic gene expression.


Assuntos
Arabidopsis/enzimologia , Fibroblastos/enzimologia , Integrases/genética , Plasmídeos/genética , Protoplastos/enzimologia , Recombinação Genética , Serina/genética , Animais , Bovinos , Humanos , Integrases/metabolismo , Leucócitos Mononucleares/enzimologia , Regiões Promotoras Genéticas , Serina/metabolismo
8.
J Proteomics ; 217: 103690, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32068185

RESUMO

Arachis stenosperma is a wild peanut relative exclusive to South America that harbors high levels of resistance against several pathogens, including the peanut root-knot nematode (RKN) Meloidogyne arenaria. In this study, a proteomic survey of A. stenosperma-M. arenaria interaction using 2-DE and LC-MS/MS identified approximately 1400 proteins, out of which 222 were differentially abundant (DAPs) when RKN inoculated root samples were compared to the control. Most of these DAPs were assigned to functional categories related to plant responses to pathogens including stress, glycolysis, redox and tricarboxylic acid cycle. The comparison between the transcriptome (RNA-Seq) and proteome expression changes, showed that almost 55% of these DAPs encode genes with a similar expression trend to their protein counterparts. Most of these genes were induced during RKN infection and some were related to plant defense, such as MLP-like protein 34 (MLP34), cinnamoyl-CoA reductase 1 (CCR1), enolase (ENO), alcohol dehydrogenase (ADH) and eukaryotic translation initiation factor 5A (eIF5A). The overexpression of AsMLP34 in Agrobacterium rhizogenes transgenic roots in a susceptible peanut cultivar showed a reduction in the number of M. arenaria galls and egg masses, indicating that AsMLP34 is a promising candidate gene to be exploited in breeding programs for RKN control in peanut. SIGNIFICANCE: The use of an integrated approach to compare plant-nematode transcriptional and translational data enabled the identification of a new gene, AsMLP34, for Meloidogyne resistance.


Assuntos
Tylenchoidea , Agrobacterium , Animais , Arachis/genética , Cromatografia Líquida , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Raízes de Plantas , Proteômica , América do Sul , Espectrometria de Massas em Tandem
9.
PLoS One ; 14(8): e0220656, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31386688

RESUMO

Following the treads of our previous works on the unveiling of bioactive peptides encrypted in plant proteins from diverse species, the present manuscript reports the occurrence of four proof-of-concept intragenic antimicrobial peptides in human proteins, named Hs IAPs. These IAPs were prospected using the software Kamal, synthesized by solid phase chemistry, and had their interactions with model phospholipid vesicles investigated by differential scanning calorimetry and circular dichroism. Their antimicrobial activity against bacteria, yeasts and filamentous fungi was determined, along with their cytotoxicity towards erythrocytes. Our data demonstrates that Hs IAPs are capable to bind model membranes while attaining α-helical structure, and to inhibit the growth of microorganisms at concentrations as low as 1µM. Hs02, a novel sixteen residue long internal peptide (KWAVRIIRKFIKGFIS-NH2) derived from the unconventional myosin 1h protein, was further investigated in its capacity to inhibit lipopolysaccharide-induced release of TNF-α in murine macrophages. Hs02 presented potent anti-inflammatory activity, inhibiting the release of TNF-α in LPS-primed cells at the lowest assayed concentration, 0.1 µM. A three-dimensional solution structure of Hs02 bound to DPC micelles was determined by Nuclear Magnetic Resonance. Our work exemplifies how the human genome can be mined for molecules with biotechnological potential in human health and demonstrates that IAPs are actual alternatives to antimicrobial peptides as pharmaceutical agents or in their many other putative applications.


Assuntos
Anti-Infecciosos/síntese química , Anti-Inflamatórios/síntese química , Peptídeos/farmacologia , Animais , Eritrócitos/efeitos dos fármacos , Humanos , Lipossomos/metabolismo , Macrófagos/metabolismo , Camundongos , Micelas , Peptídeos/análise , Peptídeos/síntese química , Peptídeos/metabolismo , Conformação Proteica em alfa-Hélice , Proteínas/química , Técnicas de Síntese em Fase Sólida , Fator de Necrose Tumoral alfa/metabolismo
10.
Toxicon ; 167: 10-19, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31173792

RESUMO

The present work reports the isolation, characterization and the complete sequence of a phospholipase A2 (PLA2) present in the skin secretion of Pithecopus azureus. Among several peptides and small proteins previously described by our group from some species belonging to this amphibian genus (formerly named Phyllomedusa), a 15 kDa N-glycosylated protein showing PLA2 activity was purified, assayed, sequenced and named Pa-PLA2. The Pithecopus azureus skin phospholipase A2 polypeptide chain is composed by 125 amino acid residues linked by seven disulfide bonds and two N-glycosylated sites (N67 and N108). The Pa-PLA2 enzymatic activity was qualitatively evaluated and compared to classical viperid PLA2 showing that both, native and deglycosylated Pa-PLA2 forms, are catalytically functional. The tridimensional molecular model of Pa-PLA2 indicates that the observed glycan moieties are suggestively placed far from the active site of that enzyme and therefore having little or no significant role on the direct interaction of the Pa-PLA2 catalytic pocket and its substrates.


Assuntos
Anuros , Fosfolipases A2/química , Sequência de Aminoácidos , Animais , Fracionamento Químico , Cromatografia Líquida , Modelos Moleculares , Fosfolipases A2/isolamento & purificação , Análise de Sequência de Proteína , Espectrometria de Massas em Tandem
11.
Proteomics ; 19(13): e1900082, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31050381

RESUMO

Fully sequenced genomes of Xanthomonas campestris pv. campestris (Xcc) strains are reported. However, intra-pathovar differences are still intriguing and far from clear. In this work, the contrasting virulence between two isolates of Xcc - Xcc51 (more virulent) and XccY21 (less virulent) is evaluated by determining their pan proteome profiles. The bacteria are grown in NYG and XVM1 (optimal for induction of hrp regulon) broths and collected at the max-exponential growth phase. Shotgun proteomics reveals a total of 329 proteins when Xcc isolates are grown in XVM1. A comparison of both profiles reveals 47 proteins with significant abundance fluctuations, out of which, 39 show an increased abundance in Xcc51 and are mainly involved in virulence/adaptation mechanisms, genetic information processing, and membrane receptor/iron transport systems, such as BfeA, BtuB, Cap, Clp, Dcp, FyuA, GroEs, HpaG, Tig, and OmpP6. Several differential proteins are further analyzed by qRT-PCR, which reveals a similar expression pattern to the protein abundance. The data shed light on the complex Xcc pathogenicity mechanisms and point out a set of proteins related to the higher virulence of Xcc51. This information is essential for the development of more efficient strategies aiming at the control of black rot disease.


Assuntos
Proteínas de Bactérias/análise , Proteoma/análise , Fatores de Virulência/análise , Xanthomonas campestris/patogenicidade , Proteínas de Bactérias/genética , Meios de Cultura/química , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica/genética , Proteoma/genética , Virulência/genética , Fatores de Virulência/genética , Xanthomonas campestris/genética , Xanthomonas campestris/isolamento & purificação
12.
Front Plant Sci ; 9: 904, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29997646

RESUMO

The pathogenicity of phytonematodes relies on secreted virulence factors to rewire host cellular pathways for the benefits of the nematode. In the root-knot nematode (RKN) Meloidogyne incognita, thousands of predicted secreted proteins have been identified and are expected to interact with host proteins at different developmental stages of the parasite. Identifying the host targets will provide compelling evidence about the biological significance and molecular function of the predicted proteins. Here, we have focused on the hub protein CSN5, the fifth subunit of the pleiotropic and eukaryotic conserved COP9 signalosome (CSN), which is a regulatory component of the ubiquitin/proteasome system. We used affinity purification-mass spectrometry (AP-MS) to generate the interaction network of CSN5 in M. incognita-infected roots. We identified the complete CSN complex and other known CSN5 interaction partners in addition to unknown plant and M. incognita proteins. Among these, we described M. incognita PASSE-MURAILLE (MiPM), a small pioneer protein predicted to contain a secretory peptide that is up-regulated mostly in the J2 parasitic stage. We confirmed the CSN5-MiPM interaction, which occurs in the nucleus, by bimolecular fluorescence complementation (BiFC). Using MiPM as bait, a GST pull-down assay coupled with MS revealed some common protein partners between CSN5 and MiPM. We further showed by in silico and microscopic analyses that the recombinant purified MiPM protein enters the cells of Arabidopsis root tips in a non-infectious context. In further detail, the supercharged N-terminal tail of MiPM (NTT-MiPM) triggers an unknown host endocytosis pathway to penetrate the cell. The functional meaning of the CSN5-MiPM interaction in the M. incognita parasitism is discussed. Moreover, we propose that the cell-penetrating properties of some M. incognita secreted proteins might be a non-negligible mechanism for cell uptake, especially during the steps preceding the sedentary parasitic phase.

13.
Lancet Oncol ; 18(11): 1467-1482, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28958504

RESUMO

BACKGROUND: Rilotumumab is a fully human monoclonal antibody that selectively targets the ligand of the MET receptor, hepatocyte growth factor (HGF). We aimed to assess the efficacy, safety, and pharmacokinetics of rilotumumab combined with epirubicin, cisplatin, and capecitabine, and to assess potential biomarkers, in patients with advanced MET-positive gastric or gastro-oesophageal junction adenocarcinoma. METHODS: This multicentre, randomised, double-blind, placebo-controlled, phase 3 study was done at 152 centres in 27 countries. We recruited adults (aged ≥18 years) with unresectable locally advanced or metastatic gastric or gastro-oesophageal junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, MET-positive tumours (≥25% of tumour cells with membrane staining of ≥1+ staining intensity), and evaluable disease, who had not received previous systemic therapy. Eligible patients were randomly assigned (1:1) via a computerised voice response system to receive rilotumumab 15 mg/kg intravenously or placebo in combination with open-label chemotherapy (epirubicin 50 mg/m2 intravenously; cisplatin 60 mg/m2 intravenously; capecitabine 625 mg/m2 orally twice daily) in 21-day cycles for up to ten cycles. After completion of chemotherapy, patients continued to receive rilotumumab or placebo monotherapy until disease progression, intolerability, withdrawal of consent, or study termination. Randomisation was stratified by disease extent and ECOG performance status. Both patients and physicians were masked to study treatment assignment. The primary endpoint was overall survival, analysed by intention to treat. We report the final analysis. This study is registered with ClinicalTrials.gov, number NCT01697072. FINDINGS: Between Nov 7, 2012, and Nov 21, 2014, 609 patients were randomly assigned to rilotumumab plus epirubicin, cisplatin, and capecitabine (rilotumumab group; n=304) or placebo plus epirubicin, cisplatin, and capecitabine (placebo group; n=305). Study treatment was stopped early after an independent data monitoring committee found a higher number of deaths in the rilotumumab group than in the placebo group; all patients in the rilotumumab group subsequently discontinued all study treatment. Median follow-up was 7·7 months (IQR 3·6-12·0) for patients in the rilotumumab group and 9·4 months (5·3-13·1) for patients in the placebo group. Median overall survival was 8·8 months (95% CI 7·7-10·2) in the rilotumumab group compared with 10·7 months (9·6-12·4) in the placebo group (stratified hazard ratio 1·34, 95% CI 1·10-1·63; p=0·003). The most common grade 3 or worse adverse events in the rilotumumab and placebo groups were neutropenia (86 [29%] of 298 patients vs 97 [32%] of 299 patients), anaemia (37 [12%] vs 43 [14%]), and fatigue (30 [10%] vs 35 [12%]). The frequency of serious adverse events was similar in the rilotumumab and placebo groups (142 [48%] vs 149 [50%]). More deaths due to adverse events occurred in the rilotumumab group than the placebo group (42 [14%] vs 31 [10%]). In the rilotumumab group, 33 (11%) of 298 patients had fatal adverse events due to disease progression, and nine (3%) had fatal events not due to disease progression. In the placebo group, 23 (8%) of 299 patients had fatal adverse events due to disease progression, and eight (3%) had fatal events not due to disease progression. INTERPRETATION: Ligand-blocking inhibition of the MET pathway with rilotumumab is not effective in improving clinical outcomes in patients with MET-positive gastric or gastro-oesophageal adenocarcinoma. FUNDING: Amgen.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Capecitabina/administração & dosagem , Capecitabina/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Humanos , Internacionalidade , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas c-met/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Análise de Sobrevida , Resultado do Tratamento
14.
Sci Rep ; 7(1): 4197, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646205

RESUMO

In recent years the antimicrobial peptides (AMPs) have been prospected and designed as new alternatives to conventional antibiotics. Indeed, AMPs have presented great potential toward pathogenic bacterial strains by means of complex mechanisms of action. However, reports have increasingly emerged regarding the mechanisms by which bacteria resist AMP administration. In this context, we performed a comparative proteomic study by using the total bacterial lysate of magainin I-susceptible and -resistant E. coli strains. After nanoUPLC-MSE analyses we identified 742 proteins distributed among the experimental groups, and 25 proteins were differentially expressed in the resistant strains. Among them 10 proteins involved in bacterial resistance, homeostasis, nutrition and protein transport were upregulated, while 15 proteins related to bacterial surface modifications, genetic information and ß-lactams binding-protein were downregulated. Moreover, 60 exclusive proteins were identified in the resistant strains, among which biofilm and cell wall formation and multidrug efflux pump proteins could be observed. Thus, differentially from previous studies that could only associate single proteins to AMP bacterial resistance, data here reported show that several metabolic pathways may be related to E. coli resistance to AMPs, revealing the crucial role of multiple "omics" studies in order to elucidate the global molecular mechanisms involved in this resistance.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Magaininas/farmacologia , Espectrometria de Massas , Nanotecnologia , Cromatografia Líquida de Alta Pressão , Proteínas de Escherichia coli/metabolismo
15.
Proteomics ; 17(12)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28471538

RESUMO

Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot, a highly destructive disease that affects all brassicas. This work aimed to study the interaction Xcc-Brassica oleracea using an in vivo system in an attempt to identify proteins involved in pathogenicity. We used label-free shotgun 2D-nanoUPLC/MSE to analyze Xcc proteins in three conditions: in the interaction with susceptible (REK) and resistant (REU) plants and in culture medium (control condition). A model of Xcc-susceptible host interaction is proposed and shows that Xcc increases the abundance of several crucial proteins for infection and cell protection. In this study, we also confirmed the differential expression by qPCR analysis of selected genes. This is the first report showing a large-scale identification of proteins in an in vivo host plant condition. Considering that most studies involving phytopathogens are in vitro (growth in culture medium or in plant extract), this work contributes with relevant information related to the plant-pathogen interaction in planta.


Assuntos
Proteínas de Bactérias/metabolismo , Brassica/metabolismo , Brassica/microbiologia , Fatores de Virulência/metabolismo , Xanthomonas campestris/patogenicidade , Proteínas de Bactérias/genética , Brassica/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Proteoma/metabolismo , Fatores de Virulência/genética
16.
J Proteomics ; 151: 284-292, 2017 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-27457268

RESUMO

Tomato chlorotic mottle virus (ToCMoV) is a widespread bipartite Begomovirus species found in tomato fields in Brazil. In this study, plant responses and putative mechanisms associated with the 'Tyking'-derived recessive resistance to ToCMoV were investigated. Changes in the protein profile in the inoculated plants of two near isogenic tomato lines resistant ('LAM 157') and susceptible ('Santa Clara') to ToCMoV were analyzed. Seedlings were biolistically inoculated with an infectious ToCMoV clone. Leaves from infected plants (confirmed by PCR) were sampled at 15days after inoculation. Proteins were extracted using phenol and analyzed by shotgun MS (2D-nanoUPLC/HDMSE). Out of the 534 identified proteins, 82 presented statistically significant differences in abundance, including 35 unique proteins displayed in the resistant tomato inoculated with ToCMoV. Proteins associated to chromatin structure, cytoskeleton structure, cuticle biosynthesis, and ubiquitin pathway were identified and their putative roles during virus infection process were discussed. The protein profile analysis allowed for the development of a hypothetical model showing how the resistant host cell responds to ToCMoV infection. The data obtained provide a better understanding of resistant mechanisms used by the host plant to contain viral infection and could be the basis for further investigation in other plant-begomovirus pathosystems. BIOLOGICAL SIGNIFICANCE: In this study we propose a model of resistance to begomovirus in tomato and highlight host proteins, which could be targets for future investigations in plant-begomovirus pathosystems.


Assuntos
Begomovirus/patogenicidade , Resistência à Doença , Interações Hospedeiro-Patógeno/imunologia , Proteínas de Plantas/análise , Proteômica/métodos , Solanum lycopersicum/virologia , Brasil , Modelos Biológicos , Extratos Vegetais/química , Proteínas de Plantas/fisiologia
17.
Arq Bras Cir Dig ; 29(3): 173-179, 2016.
Artigo em Inglês, Português | MEDLINE | ID: mdl-27759781

RESUMO

In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.


Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Antineoplásicos/uso terapêutico , Brasil , Terapia Combinada , Embolização Terapêutica , Humanos
18.
ABCD (São Paulo, Impr.) ; 29(3): 173-179, July-Sept. 2016. tab
Artigo em Inglês | LILACS | ID: lil-796946

RESUMO

ABSTRACT In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.


RESUMO Neste último módulo do consenso, abordou-se alguns temas controversos. O primeiro tópico discutido foi o manejo da doença após progressão na primeira linha de quimioterapia, com foco em se ainda haveria indicação cirúrgica neste cenário. A seguir, o painel debruçou-se sobre as situações de ressecção da doença hepática na presença de doença extra-hepática, assim como, qual a melhor sequência de tratamento. O tratamento de conversão para doença inicialmente irressecável também foi abordado neste módulo, incluindo as importantes definições de quando se pode esperar que a doença se torne ressecável e quais esquemas terapêuticos seriam mais efetivos à luz dos conhecimentos atuais sobre a biologia tumoral e taxas de resposta objetiva. Por último, o tratamento da doença não passível de ressecção foi discutida, focando-se nos melhores esquemas a serem empregados e seu sequenciamento, bem como o papel da quimioembolização no manejo destes pacientes.


Assuntos
Humanos , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Brasil , Terapia Combinada , Embolização Terapêutica , Antineoplásicos/uso terapêutico
19.
J Proteomics ; 131: 8-16, 2016 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-26459402

RESUMO

Bone resorption is an important factor in bone homeostasis and imbalance can cause several diseases. In osteoimmunology, IL-4 has been described as an important factor in promoting M2 macrophage profile. In order to shed some light on the effect of IL-4 on osteoclast precursors in the presence of RANKL, cytokines and nitric oxide (NO) production and the proteomic profile were analyzed. The presence of IL-4 in in vitro osteoclastogenesis provides production of TNF-α, IL-1α, IL-1ß, IL-10 and IL-12 at basal cell levels. Regarding NO production, IL-4 was sufficient to increase the basal NO levels. Proteomic analyses identified 877 global proteins. IL-4 in in vitro RANKL-mediated osteoclastogenesis leads to the expression of 118 proteins. The presence of rIL-4 in in vitro rRANKL-mediated-osteoclastogenesis downregulated this process. However, the proteomics findings in the osteoclastogenesis demonstrated a much greater effect on osteoclast precursor cells than on RANKL-differentiated osteoclasts. These results suggest that the main effect of IL-4 in pre-osteoclast cells leads to a M2 macrophage activation, and this probably contributed to a reduction in osteoclastogenesis when both stimuli were used. This study noticed that IL-4 plays an important regulatory role in bone homeostasis due to its suppressive potential of precursor osteoclast cells.


Assuntos
Sobrevivência Celular/imunologia , Cromatografia Líquida/métodos , Interleucina-4/imunologia , Espectrometria de Massas/métodos , Osteoclastos/imunologia , Ligante RANK/imunologia , Animais , Regulação para Baixo/imunologia , Camundongos , Osteoclastos/patologia , Proteoma/imunologia , Células RAW 264.7
20.
Plant Biotechnol J ; 13(7): 884-92, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25572960

RESUMO

There is an urgent need to provide effective anti-HIV microbicides to resource-poor areas worldwide. Some of the most promising microbicide candidates are biotherapeutics targeting viral entry. To provide biotherapeutics to poorer areas, it is vital to reduce the cost. Here, we report the production of biologically active recombinant cyanovirin-N (rCV-N), an antiviral protein, in genetically engineered soya bean seeds. Pure, biologically active rCV-N was isolated with a yield of 350 µg/g of dry seed weight. The observed amino acid sequence of rCV-N matched the expected sequence of native CV-N, as did the mass of rCV-N (11 009 Da). Purified rCV-N from soya is active in anti-HIV assays with an EC50 of 0.82-2.7 nM (compared to 0.45-1.8 nM for E. coli-produced CV-N). Standard industrial processing of soya bean seeds to harvest soya bean oil does not diminish the antiviral activity of recovered rCV-N, allowing the use of industrial soya bean processing to generate both soya bean oil and a recombinant protein for anti-HIV microbicide development.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Transporte/biossíntese , Engenharia de Proteínas , Sementes/genética , Fármacos Anti-HIV , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Sementes/metabolismo , /metabolismo
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