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1.
Oncol Lett ; 25(4): 173, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36970608

RESUMO

Prostate cancer (PCa) is one of the most prevalent types of cancer in men worldwide; however, the main diagnostic tests available for PCa have limitations and a biopsy is required for histopathological confirmation of the disease. Prostate-specific antigen (PSA) is the main biomarker used for the early detection of PCa, but an elevated serum concentration is not cancer-specific. Therefore, there is a need for the discovery of new non-invasive biomarkers that can accurately diagnose PCa. The present study used trichloroacetic acid-induced protein precipitation and liquid chromatography-mass spectrometry to profile endogenous peptides in urine samples from patients with PCa (n=33), benign prostatic hyperplasia (n=25) and healthy individuals (n=28). Receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of urinary peptides. In addition, Proteasix tool was used for in silico prediction of protease cleavage sites. Five urinary peptides derived from uromodulin were revealed to be significantly altered between the study groups, all of which were less abundant in the PCa group. This peptide panel showed a high potential to discriminate between the study groups, resulting in area under the curve (AUC) values between 0.788 and 0.951. In addition, urinary peptides outperformed PSA in discriminating between malignant and benign prostate conditions (AUC=0.847), showing high sensitivity (81.82%) and specificity (88%). From in silico analyses, the proteases HTRA2, KLK3, KLK4, KLK14 and MMP25 were identified as potentially involved in the degradation of uromodulin peptides in the urine of patients with PCa. In conclusion, the present study allowed the identification of urinary peptides with potential for use as non-invasive biomarkers in PCa diagnosis.

2.
Biochimie ; 198: 141-154, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35367578

RESUMO

Li-Fraumeni and Li-Fraumeni-like syndromes (LFS/LFL) are hereditary cancer predisposition disorders associated with germline mutations in the TP53 tumor suppressor gene. Here, we stably expressed LFS/LFL-associated p53 mutants R337H and G245S in p53-null H1299 cells to study their cellular and molecular effects. Mutant proteins showed distinct oligomerization states and opposing effects on cell proliferation and viability. Stable expression of p53G245S enhanced cell proliferation and spheroid formation, while cells stably expressing p53R337H showed reduced proliferation and clonogenicity, along with increased cell death. Mass spectrometry analysis revealed that proteins whose expression was induced by p53R337H or p53G245S expression were related to distinct metabolic profiles. Proteins upregulated by p53G245S expression were associated with a Warburg phenotype, while proteins upregulated by p53R337H expression were related to oxidative phosphorylation and fatty acid oxidation. Differences in mitochondrial mass and activity between cells stably expressing p53R337H or p53G245S were further corroborated by High Resolution Respirometry, flow cytometry and qPCR assays. The implications of the different oncogenic properties of p53R337H and p53G245S on the clinical manifestation and treatment of LFS/LFL patients carrying these mutations are discussed.


Assuntos
Síndrome de Li-Fraumeni , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/patologia , Redes e Vias Metabólicas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
3.
Parasit Vectors ; 15(1): 99, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35313982

RESUMO

BACKGROUND: Most cystic echinococcosis cases in Southern Brazil are caused by Echinococcus granulosus and Echinococcus ortleppi. Proteomic studies of helminths have increased our knowledge about the molecular survival strategies that are used by parasites. Here, we surveyed the protein content of the hydatid fluid compartment in E. granulosus and E. ortleppi pulmonary bovine cysts to better describe and compare their molecular arsenal at the host-parasite interface. METHODS: Hydatid fluid samples from three isolates of each species were analyzed using mass spectrometry-based proteomics (LC-MS/MS). In silico functional analyses of the identified proteins were performed to examine parasite survival strategies. RESULTS: The identified hydatid fluid protein profiles showed a predominance of parasite proteins compared to host proteins that infiltrate the cysts. We identified 280 parasitic proteins from E. granulosus and 251 from E. ortleppi, including 52 parasitic proteins that were common to all hydatid fluid samples. The in silico functional analysis revealed important molecular functions and processes that are active in pulmonary cystic echinococcosis, such as adhesion, extracellular structures organization, development regulation, signaling transduction, and enzyme activity. CONCLUSIONS: The protein profiles described here provide evidence of important mechanisms related to basic cellular processes and functions that act at the host-parasite interface in cystic echinococcosis. The molecular tools used by E. granulosus and E. ortleppi for survival within the host are potential targets for new therapeutic approaches to treat cystic echinococcosis and other larval cestodiases.


Assuntos
Equinococose Pulmonar , Echinococcus granulosus , Animais , Bovinos , Cromatografia Líquida , Proteômica , Espectrometria de Massas em Tandem
4.
Parasit Vectors, v. 15, 99, mar. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4269

RESUMO

Background Most cystic echinococcosis cases in Southern Brazil are caused by Echinococcus granulosus and Echinococcus ortleppi. Proteomic studies of helminths have increased our knowledge about the molecular survival strategies that are used by parasites. Here, we surveyed the protein content of the hydatid fluid compartment in E. granulosus and E. ortleppi pulmonary bovine cysts to better describe and compare their molecular arsenal at the host-parasite interface. Methods Hydatid fluid samples from three isolates of each species were analyzed using mass spectrometry-based proteomics (LC-MS/MS). In silico functional analyses of the identified proteins were performed to examine parasite survival strategies. Results The identified hydatid fluid protein profiles showed a predominance of parasite proteins compared to host proteins that infiltrate the cysts. We identified 280 parasitic proteins from E. granulosus and 251 from E. ortleppi, including 52 parasitic proteins that were common to all hydatid fluid samples. The in silico functional analysis revealed important molecular functions and processes that are active in pulmonary cystic echinococcosis, such as adhesion, extracellular structures organization, development regulation, signaling transduction, and enzyme activity. Conclusions The protein profiles described here provide evidence of important mechanisms related to basic cellular processes and functions that act at the host-parasite interface in cystic echinococcosis. The molecular tools used by E. granulosus and E. ortleppi for survival within the host are potential targets for new therapeutic approaches to treat cystic echinococcosis and other larval cestodiases.

5.
Cancer Diagn Progn ; 1(3): 235-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35399307

RESUMO

Background: Drug resistance is the main cause of therapy failure in advanced lung cancer. Although non-genetic mechanisms play important roles in tumor chemoresistance, drug-induced epigenetic reprogramming is still poorly understood. Materials and Methods: The A549 cell line was used to generate cells with non-genetic resistance to cisplatin (CDDP), namely A549/CDDP cells. Bioorthogonal non-canonical amino acid tagging (BONCAT) and mass spectrometry were used to identify proteins modulated by CDDP in A549 and A549/CDDP cells. Results: Proteins related to proteostasis, telomere maintenance, cell adhesion, cytoskeletal remodeling, and cell redox homeostasis were found enriched in both cell lines upon CDDP exposure. On the other hand, proteins involved in drug response, metabolic pathways and mRNA processing and splicing were up-regulated by CDDP only in A549/CDDP cells. Conclusion: Our study revealed proteome dynamics involved in the non-genetic response to CDDP, pointing out potential targets to monitor and overcome epigenetic resistance in lung cancer.

6.
J Proteomics ; 228: 103939, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32798775

RESUMO

Mesocestoides corti (syn. vogae) is a useful model for developmental studies of platyhelminth parasites of the Cestoda class, such as Taenia spp. or Echinococcus spp. It has been used in studies to characterize cestode strobilation, i.e. the development of larvae into adult worms. So far, little is known about the initial molecular events involved in cestode strobilation and, therefore, we carried out a study to characterize newly synthesized (NS) proteins upon strobilation induction. An approach based on bioorthogonal noncanonical amino acid tagging and mass spectrometry was used to label, isolate, identify, and quantify NS proteins in the initial steps of M. corti strobilation. Overall, 121 NS proteins were detected exclusively after induction of strobilation, including proteins related to development pathways, such as insulin and notch signaling. Metabolic changes that take place in the transition from the larval stage to adult worm were noted in special NS protein subsets related to developmental processes, such as focal adhesion, cell leading edge, and maintenance of location. The data shed light on mechanisms underlying early steps of cestode strobilation and enabled identification of possible developmental markers. We also consider the use of developmental responsive proteins as potential drug targets for developing novel anthelmintics. BIOLOGICAL SIGNIFICANCE: Larval cestodiases are life-threatening parasitic diseases that affect both man and domestic animals worldwide. Cestode parasites present complex life cycles, in which they undergo major morphological and physiological changes in the transition from one life-stage to the next. One of these transitions occurs during cestode strobilation, when the mostly undifferentiated and non-segmented larval or pre-adult form develops into a fully segmented and sexually differentiated (strobilated) adult worm. Although the proteomes of bona fide larvae and strobialted adults have been previously characterized for a few cestode species, little is still known about the dynamic of protein synthesis during the early steps of cestode strobilation. Now, the assessment of newly synthesized (NS) proteins within the first 48 h of strobilation the model cestode M. corti allowed to shed light on molecular mechanisms that are triggered by strobilation induction. The functional analyses of this repertoire of over a hundred NS proteins pointed out to changes in metabolism and activation of classical developmental signaling pathways in early strobilation. Many of the identified NS proteins may become valuable cestode developmental markers and their involvement in vital processes make them also good candidate targets for novel anthelmintic drugs.


Assuntos
Cestoides , Mesocestoides , Parasitos , Animais , Estágios do Ciclo de Vida , Proteoma
7.
Pathogens ; 9(6)2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32545493

RESUMO

Echinococcus granulosus has a complex life cycle involving two mammalian hosts. The transition from one host to another is accompanied by changes in gene expression, and the transcriptional events that underlie this transition have not yet been fully characterized. In this study, RNA-seq was used to compare the transcription profiles of samples from E. granulosus protoscoleces induced in vitro to strobilar development at three time points. We identified 818 differentially expressed genes, which were divided into eight expression clusters formed over the entire 24 h period. An enrichment of gene transcripts with molecular functions of signal transduction, enzymes, and protein modifications was observed upon induction and developmental progression. This transcriptomic study provides insights for understanding the complex life cycle of E. granulosus and contributes for searching for the key genes correlating with the strobilar development, which can be used to identify potential candidates for the development of anthelmintic drugs.

8.
Sci Rep ; 10(1): 1242, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988353

RESUMO

The aim of this study was to establish a peptidomic profile based on LC-MS/MS and random forest (RF) algorithm to distinguish the urinary peptidomic scenario of type 2 diabetes mellitus (T2DM) patients with different stages of diabetic kidney disease (DKD). Urine from 60 T2DM patients was collected: 22 normal (stage A1), 18 moderately increased (stage A2) and 20 severely increased (stage A3) albuminuria. A total of 1080 naturally occurring peptides were detected, which resulted in the identification of a total of 100 proteins, irrespective of the patients' renal status. The classification accuracy showed that the most severe DKD (A3) presented a distinct urinary peptidomic pattern. Estimates for peptide importance assessed during RF model training included multiple fragments of collagen and alpha-1 antitrypsin, previously associated to DKD. Proteasix tool predicted 48 proteases potentially involved in the generation of the 60 most important peptides identified in the urine of DM patients, including metallopeptidases, cathepsins, and calpains. Collectively, our study lightened some biomarkers possibly involved in the pathogenic mechanisms of DKD, suggesting that peptidomics is a valuable tool for identifying the molecular mechanisms underpinning the disease and thus novel therapeutic targets.


Assuntos
Nefropatias Diabéticas/diagnóstico , Peptídeos/análise , Peptídeos/urina , Idoso , Algoritmos , Biomarcadores/urina , Cromatografia Líquida/métodos , Biologia Computacional/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteoma/análise , Espectrometria de Massas em Tandem/métodos , Urina/química
9.
PLoS Negl Trop Dis ; 12(5): e0006473, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29727452

RESUMO

BACKGROUND: Cystic hydatid disease is a zoonosis caused by the larval stage (hydatid) of Echinococcus granulosus (Cestoda, Taeniidae). The hydatid develops in the viscera of intermediate host as a unilocular structure filled by the hydatid fluid, which contains parasitic excretory/secretory products. The lipoprotein Antigen B (AgB) is the major component of E. granulosus metacestode hydatid fluid. Functionally, AgB has been implicated in immunomodulation and lipid transport. However, the mechanisms underlying AgB functions are not completely known. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated AgB interactions with different mammalian cell types and the pathways involved in its internalization. AgB uptake was observed in four different cell lines, NIH-3T3, A549, J774 and RH. Inhibition of caveolae/raft-mediated endocytosis causes about 50 and 69% decrease in AgB internalization by RH and A549 cells, respectively. Interestingly, AgB colocalized with the raft endocytic marker, but also showed a partial colocalization with the clathrin endocytic marker. Finally, AgB colocalized with an endolysosomal tracker, providing evidence for a possible AgB destination after endocytosis. CONCLUSIONS/SIGNIFICANCE: The results indicate that caveolae/raft-mediated endocytosis is the main route to AgB internalization, and that a clathrin-mediated entry may also occur at a lower frequency. A possible fate for AgB after endocytosis seems to be the endolysosomal system. Cellular internalization and further access to subcellular compartments could be a requirement for AgB functions as a lipid carrier and/or immunomodulatory molecule, contributing to create a more permissive microenvironment to metacestode development and survival.


Assuntos
Antígenos de Helmintos/metabolismo , Equinococose/parasitologia , Echinococcus granulosus/metabolismo , Endocitose , Proteínas de Helminto/metabolismo , Animais , Linhagem Celular , Equinococose/fisiopatologia , Echinococcus granulosus/genética , Humanos , Camundongos
10.
J Proteomics ; 175: 127-135, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29317356

RESUMO

Mesocestoides corti is a widely used model for the study of cestode biology, and its transition from the larval tetrathyridium (TT) stage to the strobilated, adult worm (ST) stage can be induced and followed in vitro. Here, a proteomic approach was used to describe and compare M. corti TT and ST protein repertories. Overall, 571 proteins were identified, 238 proteins in TT samples and 333 proteins in ST samples. Among the identified proteins, 207 proteins were shared by TTs and STs, while 157 were stage-specific, being 31 exclusive from TTs, and 126 from STs. Functional annotation revealed fundamental metabolic differences between the TT and the ST stages. TTs perform functions related mainly to basic metabolism, responsible for growth and vegetative development by asexual reproduction. STs, in contrast, perform a wider range of functions, including macromolecule biosynthetic processes, gene expression and control pathways, which may be associated to its proglottization/segmentation, sexual differentiation and more complex physiology. Furthermore, the generated results provided an extensive list of cestode proteins of interest for functional studies in M. corti. Many of these proteins are novel candidate diagnostic antigens, and/or potential targets for the development of new and more effective antihelminthic drugs. BIOLOGICAL SIGNIFICANCE: Cestodiases are parasitic diseases with serious impact on human and animal health. Efforts to develop more effective strategies for diagnosis, treatment or control of cestodiases are impaired by the still limited knowledge on many aspects of cestode biology, including the complex developmental processes that occur in the life cycles of these parasites. Mesocestoides corti is a good experimental model to study the transition from the larval to the adult stage, called strobilation, which occur in typical cestode life-cycles. The performed proteomics approach provided large-scale identification and quantification of M. corti proteins. Many stage-specific or differentially expressed proteins were detected in the larval tetrathyridium (TT) stage and in the strobilated, adult worm (ST) stage. Functional comparative analyses of the described protein repertoires shed light on function and processes associated to specific features of both stages, such as less differentiation and asexual reproduction in TTs, and proglottization/segmentation and sexual differentiation in ST. Moreover, many of the identified stage-specific proteins are useful as cestode developmental markers, and are potential targets for development of novel diagnostic methods and therapeutic drugs for cestodiases.


Assuntos
Larva/metabolismo , Estágios do Ciclo de Vida , Proteômica/métodos , Animais , Cestoides/química , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/tratamento farmacológico , Proteínas de Helminto/análise , Proteínas de Helminto/fisiologia , Humanos , Mesocestoides/química , Reprodução Assexuada , Diferenciação Sexual
11.
Mol Biochem Parasitol ; 211: 39-47, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27638150

RESUMO

Toxocariasis is a neglected disease, and its main etiological agent is the nematode Toxocara canis. Serological diagnosis is performed by an enzyme-linked immunosorbent assay using T. canis excretory and secretory (TES) antigens produced by in vitro cultivation of larvae. Identification of TES proteins can be useful for the development of new diagnostic strategies since few TES components have been described so far. Herein, we report the results obtained by proteomic analysis of TES proteins using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach. TES fractions were separated by one-dimensional SDS-PAGE and analyzed by LC-MS/MS. The MS/MS spectra were compared with a database of protein sequences deduced from the genome sequence of T. canis, and a total of 19 proteins were identified. Classification according to the signal peptide prediction using the SignalP server showed that seven of the identified proteins were extracellular, 10 had cytoplasmic or nuclear localization, while the subcellular localization of two proteins was unknown. Analysis of molecular functions by BLAST2GO showed that the majority of the gene ontology (GO) terms associated with the proteins present in the TES sample were associated with binding functions, including but not limited to protein binding (GO:0005515), inorganic ion binding (GO:0043167), and organic cyclic compound binding (GO:0097159). This study provides additional information about the exoproteome of T. canis, which can lead to the development of new strategies for diagnostics or vaccination.


Assuntos
Exossomos/metabolismo , Proteínas de Helminto/metabolismo , Proteoma , Proteômica , Vesículas Secretórias/metabolismo , Toxocara canis/metabolismo , Animais , Cromatografia Líquida , Biologia Computacional/métodos , Cães , Feminino , Proteômica/métodos , Espectrometria de Massas em Tandem , Toxocaríase/parasitologia
12.
PLoS Negl Trop Dis ; 10(10): e0005061, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27736880

RESUMO

Accumulating evidences have assigned a central role to parasite-derived proteins in immunomodulation. Here, we report on the proteomic identification and characterization of immunomodulatory excretory-secretory (ES) products from the metacestode larva (tetrathyridium) of the tapeworm Mesocestoides corti (syn. M. vogae). We demonstrate that ES products but not larval homogenates inhibit the stimuli-driven release of the pro-inflammatory, Th1-inducing cytokine IL-12p70 by murine bone marrow-derived dendritic cells (BMDCs). Within the ES fraction, we biochemically narrowed down the immunosuppressive activity to glycoproteins since active components were lipid-free, but sensitive to heat- and carbohydrate-treatment. Finally, using bioassay-guided chromatographic analyses assisted by comparative proteomics of active and inactive fractions of the ES products, we defined a comprehensive list of candidate proteins released by M. corti tetrathyridia as potential suppressors of DC functions. Our study provides a comprehensive library of somatic and ES products and highlight some candidate parasite factors that might drive the subversion of DC functions to facilitate the persistence of M. corti tetrathyridia in their hosts.


Assuntos
Infecções por Cestoides/imunologia , Células Dendríticas/imunologia , Proteínas de Helminto/imunologia , Mesocestoides/química , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/parasitologia , Infecções por Cestoides/parasitologia , Células Dendríticas/parasitologia , Proteínas de Helminto/química , Proteínas de Helminto/genética , Humanos , Larva/química , Larva/genética , Larva/imunologia , Mesocestoides/genética , Mesocestoides/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteômica
13.
Vet Parasitol ; 218: 43-5, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26872926

RESUMO

Echinococcus granulosus protoscolex proteins were separated using two-dimensional electrophoresis and then identified using mass spectrometry; we identified 61 proteins, 28 which are newly described of which 4 could be involved in hydatid cyst fertility molecular mechanisms.


Assuntos
Echinococcus granulosus/genética , Echinococcus granulosus/metabolismo , Proteínas de Helminto/metabolismo , Proteômica , Animais , Eletroforese em Gel de Poliacrilamida , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Helminto/genética , Proteínas de Helminto/isolamento & purificação , Estágios do Ciclo de Vida
14.
PLoS Negl Trop Dis ; 9(9): e0004085, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26393918

RESUMO

BACKGROUND: The proteins responsible for the key molecular events leading to the structural changes between the developmental stages of Echinococcus granulosus remain unknown. In this work, azidohomoalanine (AHA)-specific labeling was used to identify proteins expressed by E. granulosus protoscoleces (PSCs) upon the induction of strobilar development. METHODOLOGY/PRINCIPAL FINDINGS: The in vitro incorporation of AHA with different tags into newly synthesized proteins (NSPs) by PSCs was analyzed using SDS-PAGE and confocal microscopy. The LC-MS/MS analysis of AHA-labeled NSPs by PSCs undergoing strobilation allowed for the identification of 365 proteins, of which 75 were differentially expressed in comparison between the presence or absence of strobilation stimuli and 51 were expressed exclusively in either condition. These proteins were mainly involved in metabolic, regulatory and signaling processes. CONCLUSIONS/SIGNIFICANCE: After the controlled-labeling of proteins during the induction of strobilar development, we identified modifications in protein expression. The changes in the metabolism and the activation of control and signaling pathways may be important for the correct parasite development and be target for further studies.


Assuntos
Echinococcus granulosus/química , Echinococcus granulosus/fisiologia , Proteínas de Helminto/análise , Matadouros , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Cromatografia Líquida , Equinococose/parasitologia , Equinococose/veterinária , Eletroforese em Gel de Poliacrilamida , Perfilação da Expressão Gênica , Estágios do Ciclo de Vida , Microscopia Confocal , Espectrometria de Massas em Tandem
15.
J Proteomics ; 119: 230-7, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25724729

RESUMO

Listeria monocytogenes infections have been frequently reported in many food poisoning outbreaks around the world. In this work, the protein repertoires of L. monocytogenes ATCC 7644 cells treated or not with a 10(-3)mg/mL nisin sublethal concentration, established by antimicrobial susceptibility tests, were analyzed by LC-MS/MS. Overall, 179 proteins were identified, 9 of them more abundant in nisin-treated samples, and 4 more abundant in non-treated control samples. In nisin treated cells, proteins associated to oxidative stress response showed higher abundance. Also, the higher abundance of an enzyme related to the production of cell membrane lipids upon nisin exposure is suggestive of both a failure in conventional cell division mechanism and the activation of an alternative L-form mediated division mechanism. Finally, flagellar and motility proteins' overexpression upon nisin exposure is indicative of increased bacterial motility in response to the bacteriocin. Taken together, these results provide new insights on nisin effects on L. monocytogenes cells and on how this bacterium may overcome a bacteriocin-containing environment. BIOLOGICAL SIGNIFICANCE: The antimicrobial mechanism of nisin on target bacterial cells has been extensively studied since discovery of this bacteriocin. The nisin pore-forming mechanism is mediated by its binding to the pyrophosphate portion of membrane lipid II [1], but some evidences point out to alternative mechanisms. Results from assays with mutacin 1140 hybrids [2] showed that the portion of nisin that is not involved with lipid II binding could damage the bacterial cell, independently of pore formation [3,4]. Moreover, there are insufficient data to explain how nisin affects the bacterial survival. In this scenario, proteomics is an interesting approach, as a comparison between treated and untreated cells may provide insights of both antimicrobial mechanisms of action and bacterial response mechanisms [5].


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Listeria monocytogenes/metabolismo , Nisina/farmacologia , Relação Dose-Resposta a Droga , Proteômica
16.
PLoS Negl Trop Dis ; 8(9): e3176, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25233456

RESUMO

BACKGROUND: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. METHODOLOGY/PRINCIPAL FINDINGS: The T. rangeli haploid genome is ∼ 24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heat-shock proteins. CONCLUSIONS/SIGNIFICANCE: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets.


Assuntos
Genoma de Protozoário , Filogenia , Trypanosoma rangeli/genética , Animais , Sequência de Bases , DNA de Protozoário/genética , Haploidia , Humanos
17.
Acta Trop ; 140: 166-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25149354

RESUMO

Acanthamoeba polyphaga is a free-living protozoan pathogen, whose infective trophozoite form is capable of causing a blinding keratitis and fatal granulomatous encephalitis in humans. The damage caused by A. polyphaga trophozoites in human corneal or brain infections is the result of several different pathogenic mechanisms that have not yet been elucidated at the molecular level. We performed a comprehensive analysis of the proteins expressed by A. polyphaga trophozoites, based on complementary 2-DE MS/MS and gel-free LC-MS/MS approaches. Overall, 202 non-redundant proteins were identified. An A. polyphaga proteomic map in the pH range 3-10 was produced, with protein identification for 184 of 370 resolved spots, corresponding to 142 proteins. Additionally, 94 proteins were identified by gel-free LC-MS/MS. Functional classification revealed several proteins with potential importance for pathogen survival and infection of mammalian hosts, including surface proteins and proteins related to defense mechanisms. Our study provided the first comprehensive proteomic survey of the trophozoite infective stage of an Acanthamoeba species, and established foundations for prospective, comparative and functional studies of proteins involved in mechanisms of survival, development, and pathogenicity in A. polyphaga and other pathogenic amoebae.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/metabolismo , Ceratite por Acanthamoeba/prevenção & controle , Animais , Humanos , Proteômica , Espectrometria de Massas em Tandem , Trofozoítos/metabolismo
18.
Gene ; 506(1): 76-84, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22750316

RESUMO

Glycolytic enzymes, such as fructose-bisphosphate aldolase (FBA) and enolase, have been described as complex multifunctional proteins that may perform non-glycolytic moonlighting functions, but little is known about such functions, especially in parasites. We have carried out in silico genomic searches in order to identify FBA and enolase coding sequences in Echinococcus granulosus, the causative agent of cystic hydatid disease. Four FBA genes and 3 enolase genes were found, and their sequences and exon-intron structures were characterized and compared to those of their orthologs in Echinococcus multilocularis, the causative agent of alveolar hydatid disease. To gather evidence of possible non-glycolytic functions, the expression profile of FBA and enolase isoforms detected in the E. granulosus pathogenic larval form (hydatid cyst) (EgFBA1 and EgEno1) was assessed. Using specific antibodies, EgFBA1 and EgEno1 were detected in protoscolex and germinal layer cells, as expected, but they were also found in the hydatid fluid, which contains parasite's excretory-secretory (ES) products. Besides, both proteins were found in protoscolex tegument and in vitro ES products, further suggesting possible non-glycolytic functions in the host-parasite interface. EgFBA1 modeled 3D structure predicted a F-actin binding site, and the ability of EgFBA1 to bind actin was confirmed experimentally, which was taken as an additional evidence of FBA multifunctionality in E. granulosus. Overall, our results represent the first experimental evidences of alternative functions performed by glycolytic enzymes in E. granulosus and provide relevant information for the understanding of their roles in host-parasite interplay.


Assuntos
Echinococcus granulosus/enzimologia , Echinococcus granulosus/genética , Frutose-Bifosfato Aldolase/genética , Frutose-Bifosfato Aldolase/metabolismo , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA de Helmintos/genética , Equinococose/parasitologia , Echinococcus granulosus/patogenicidade , Echinococcus multilocularis/enzimologia , Echinococcus multilocularis/genética , Frutose-Bifosfato Aldolase/química , Perfilação da Expressão Gênica , Genes de Helmintos , Proteínas de Helminto/química , Interações Hospedeiro-Parasita , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Fosfopiruvato Hidratase/química , Mapeamento de Interação de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
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