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1.
Biol Res ; 57(1): 12, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561836

RESUMO

BACKGROUND: Bacterial aromatic degradation may cause oxidative stress. The long-chain flavodoxin FldX1 of Paraburkholderia xenovorans LB400 counteracts reactive oxygen species (ROS). The aim of this study was to evaluate the protective role of FldX1 in P. xenovorans LB400 during the degradation of 4-hydroxyphenylacetate (4-HPA) and 3-hydroxyphenylacetate (3-HPA). METHODS: The functionality of FldX1 was evaluated in P. xenovorans p2-fldX1 that overexpresses FldX1. The effects of FldX1 on P. xenovorans were studied measuring growth on hydroxyphenylacetates, degradation of 4-HPA and 3-HPA, and ROS formation. The effects of hydroxyphenylacetates (HPAs) on the proteome (LC-MS/MS) and gene expression (qRT-PCR) were quantified. Bioaugmentation with strain p2-fldX1 of 4-HPA-polluted soil was assessed, measuring aromatic degradation (HPLC), 4-HPA-degrading bacteria, and plasmid stability. RESULTS: The exposure of P. xenovorans to 4-HPA increased the formation of ROS compared to 3-HPA or glucose. P. xenovorans p2-fldX1 showed an increased growth on 4-HPA and 3-HPA compared to the control strain WT-p2. Strain p2-fldX1 degraded faster 4-HPA and 3-HPA than strain WT-p2. Both WT-p2 and p2-fldX1 cells grown on 4-HPA displayed more changes in the proteome than cells grown on 3-HPA in comparison to glucose-grown cells. Several enzymes involved in ROS detoxification, including AhpC2, AhpF, AhpD3, KatA, Bcp, CpoF1, Prx1 and Prx2, were upregulated by hydroxyphenylacetates. Downregulation of organic hydroperoxide resistance (Ohr) and DpsA proteins was observed. A downregulation of the genes encoding scavenging enzymes (katE and sodB), and gstA and trxB was observed in p2-fldX1 cells, suggesting that FldX1 prevents the antioxidant response. More than 20 membrane proteins, including porins and transporters, showed changes in expression during the growth of both strains on hydroxyphenylacetates. An increased 4-HPA degradation by recombinant strain p2-fldX1 in soil microcosms was observed. In soil, the strain overexpressing the flavodoxin FldX1 showed a lower plasmid loss, compared to WT-p2 strain, suggesting that FldX1 contributes to bacterial fitness. Overall, these results suggest that recombinant strain p2-fldX1 is an attractive bacterium for its application in bioremediation processes of aromatic compounds. CONCLUSIONS: The long-chain flavodoxin FldX1 improved the capability of P. xenovorans to degrade 4-HPA in liquid culture and soil microcosms by protecting cells against the degradation-associated oxidative stress.


Assuntos
Burkholderia , Burkholderiaceae , Flavodoxina , Gliceraldeído/análogos & derivados , Fenilacetatos , Propano , Biodegradação Ambiental , Flavodoxina/metabolismo , Flavodoxina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteoma/metabolismo , Proteoma/farmacologia , Cromatografia Líquida , Burkholderia/genética , Burkholderia/metabolismo , Espectrometria de Massas em Tandem , Estresse Oxidativo , Glucose/metabolismo , Solo
2.
São Paulo; s.n; s.n; 2018. 93 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-881085

RESUMO

A esporotricose é uma doença crônica que envolve o tecido subcutâneo afetando seres humanos e animais, causada pelo fungo termodimórfico Sporothrix spp.. A esporotricose é endêmica na América latina, principalmente no Brasil que teve o maior surto zoonótico já registrado, ocorrendo na cidade do Rio de Janeiro. A espécie Sporothrix brasiliensis é a mais diagnosticada no surto e a mais virulenta entre as especies de Sporothrix spp., causando formas mais graves da doença. A esporotricose em gatos é endêmica, fatal e um dos principais fatores pelo alto número de casos no Rio de Janeiro. O tratamento é longo e não vem sendo o suficiente para conter o número de casos da doença. Uma vacina contra a esporotricose poderia mudar esse paradigma no Brasil. O presente trabalho obteve o proteoma da cepa S. brasiliensis 5110 por meio de uma eletroforese 2D, e caracterizou e identificou as possíveis proteínas imunogênicas do fungo por espectrometria de massa. Por meio de programas de predição, foi avaliado e sintetizado 7 sequências de aminoácidos,das proteínas identificadas com maiores chances de se acoplar a molécula MHC de classe II. Apenas 3 foram capazes de induzir proliferação in vitro, os peptídeos ZR3, ZR4 e ZR8, que foram utilizados como vacina na esporotricose subcutânea e avaliados sua eficácia por meio da carga fúngica, diâmetro das lesões, perfil celular e níveis de citocinas. Neste trabalho concluímos que o peptídeo ZR8 foi o melhor candidato à vacina na esporotricose, pois foi capaz de diminuir o diâmetro das lesões, aumentar os níveis de citocinas protetoras (IFN-γ, IL-17A e IL-1ß) e aumentar o número de células TCD4+ e CD3-/CD19+, sendo assim induzindo uma resposta imunológica protetora na esporotricose subcutânea


Sporotrichosis is a chronic disease, which involves the subcutaneous tissue affecting humans and animals caused by the thermodymorphic fungus Sporothrix spp. Sporotrichosis is endemic in Latin America, mainly in Brazil that had the largest zoonotic outbreak ever recorded, occurring in the city of Rio de Janeiro. The Sporothrix brasiliensis is the species more diagnosed in the outbreak and most virulent, causing severe forms of the disease. Sporotrichosis in cats is endemic, fatal and the main factors due to the high number of cases of the disease in Rio de Janeiro. The treatment is long, and has not been enough to contain the number of cases of sporotrichosis. A vaccine against sporotrichosis could change this paradigm in Brazil. The present work obtained the proteome of S. brasiliensis 5110 strain by 2D electrophoresis, and characterized and identified possible immunogenic proteins by mass spectrometry. By prediction programs were evaluated and synthesized 7 peptide sequence from antigenic proteins that have the highest chances of coupling to the MHC class II molecule. From these 7 peptides only 3 were able to induce proliferation in vitro, called ZR3, ZR4 and ZR8 peptides, that were used as a vaccine in subcutaneous sporotrichosis and evaluated their efficacy through fungal load, lesion diameter, cell profile and cytokine levels. We conclude that ZR8 peptide was the best candidate for sporotrichosis vaccine, since it was able to decrease the lesion diameter, increase the levels of protective cytokines (IFN-γ, IL-17A and IL-1ß) and increase the number of CD4+ T cells and CD3-/CD19+ inducing a protective immune response in subcutaneous sporotrichosis


Assuntos
Animais , Masculino , Feminino , Camundongos , Esporotricose/complicações , Sporothrix/classificação , Vacinas/análise , Espectrometria de Massas/métodos , Western Blotting/métodos , Proteoma/farmacologia , Previsões/métodos
3.
J Agric Food Chem ; 63(22): 5335-43, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26034922

RESUMO

Several studies have described the effects of seed exudates against microorganisms, but only few of them have investigated the proteins that have defensive activity particularly against nematode parasites. This study focused on the proteins released in the exudates of soybean seeds and evaluated their nematicidal properties against Meloidogyne incognita. A proteomic approach indicated the existence of 63 exuded proteins, including ß-1,3-glucanase, chitinase, lectin, trypsin inhibitor, and lipoxygenase, all of which are related to plant defense. The presence of some of these proteins was confirmed by their in vitro activity. The soybean exudates were able to reduce the hatching of nematode eggs and to cause 100% mortality of second-stage juveniles (J2). The pretreatment of J2 with these exudates resulted in a 90% reduction of the gall number in tobacco plants. These findings suggest that the exuded proteins are directly involved in plant defense against soil pathogens, including nematodes, during seed germination.


Assuntos
Antinematódeos/química , Glycine max/química , Exsudatos de Plantas/química , Proteínas de Plantas/química , Proteoma/química , Sementes/química , Tylenchoidea/efeitos dos fármacos , Animais , Antinematódeos/metabolismo , Antinematódeos/farmacologia , Espectrometria de Massas , Exsudatos de Plantas/metabolismo , Exsudatos de Plantas/farmacologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacologia , Proteoma/metabolismo , Proteoma/farmacologia , Sementes/metabolismo , Glycine max/metabolismo , Tylenchoidea/crescimento & desenvolvimento
4.
J Proteome Res ; 12(10): 4585-98, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-23998483

RESUMO

Snake venom proteomes/peptidomes are highly complex and subject to ontogenetic changes. Individual variation in the venom proteome of juvenile snakes is poorly known. We report the proteomic analysis of venoms from 21 juvenile specimens of Bothrops jararaca of different geographical origins and correlate it with the evaluation of important venom features. Individual venoms showed similar caseinolytic activities; however, their amidolytic activities were significantly different. Rather intriguingly, plasma coagulant activity showed remarkable variability among the venoms but not the prothrombin-activating activity. LC-MS analysis showed significant differences between venoms; however, an interesting finding was the ubiquitous presence of the tripeptide ZKW, an endogenous inhibitor of metalloproteinases. Electrophoretic profiles of proteins submitted to reduction showed significant variability in total proteins, glycoproteins, and in the subproteomes of proteinases. Moreover, identification of differential bands revealed variation in most B. jararaca toxin classes. Profiles of venoms analyzed under nonreducing conditions showed less individual variability and identification of proteins in a conserved band revealed the presence of metalloproteinases and l-amino acid oxidase as common components of these venoms. Taken together, our findings suggest that individual venom proteome variability in B. jararaca exists from a very early animal age and is not a result of ontogenetic and diet changes.


Assuntos
Bothrops/metabolismo , Proteoma/metabolismo , Proteínas de Répteis/metabolismo , Peçonhas/metabolismo , Sequência de Aminoácidos , Animais , Coagulantes/química , Coagulantes/metabolismo , Coagulantes/farmacologia , Feminino , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicoproteínas/farmacologia , Humanos , Masculino , Metaloproteases/química , Metaloproteases/metabolismo , Metaloproteases/farmacologia , Anotação de Sequência Molecular , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Proteólise , Proteoma/química , Proteoma/farmacologia , Protrombina/química , Proteínas de Répteis/química , Proteínas de Répteis/farmacologia , Peçonhas/química , Peçonhas/farmacologia
5.
J Proteome Res ; 11(1): 172-88, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22142336

RESUMO

Pseudallescheria boydii is a filamentous fungus that causes a wide array of infections that can affect practically all the organs of the human body. The treatment of pseudallescheriosis is difficult since P. boydii exhibits intrinsic resistance to the majority of antifungal drugs used in the clinic and the virulence attributes expressed by this fungus are unknown. The study of the secretion of molecules is an important approach for understanding the pathogenicity of fungi. With this task in mind, we have shown that mycelial cells of P. boydii were able to actively secrete proteins into the extracellular environment; some of them were recognized by antibodies present in the serum of a patient with pseudallescheriosis. Additionally, molecules secreted by P. boydii induced in vitro irreversible damage in pulmonary epithelial cells. Subsequently, two-dimensional gel electrophoresis combined with mass spectrometry was carried out in order to start the construction of a map of secreted proteins from P. boydii mycelial cells. The two-dimensional map showed that most of the proteins (around 100 spots) were focused at pH ranging from 4 to 7 with molecular masses ranging from 14 to >117 kDa. Fifty spots were randomly selected, of which 30 (60%) were consistently identified, while 20 (40%) spots generated peptides that showed no resemblance to any known protein from other fungi and/or MS with low quality. Notably, we identified proteins involved in metabolic pathways (energy/carbohydrate, nucleotide, and fatty acid), cell wall remodeling, RNA processing, signaling, protein degradation/nutrition, translation machinery, drug elimination and/or detoxification, protection against environmental stress, cytoskeleton/movement proteins, and immunogenic molecules. Since the genome of this fungus is not sequenced, we performed enzymatic and immunodetection assays in order to corroborate the presence of some released proteins. The identification of proteins actively secreted by P. boydii provides important new information for understanding immune modulation and provides important new perspectives on the biology of this intriguing fungus.


Assuntos
Proteínas Fúngicas/metabolismo , Genoma Fúngico , Micélio/metabolismo , Micoses/microbiologia , Proteoma/metabolismo , Pseudallescheria/metabolismo , Sequência de Aminoácidos , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Linhagem Celular Tumoral , Eletroforese em Gel Bidimensional , Proteínas Fúngicas/química , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/farmacologia , Humanos , Concentração Inibidora 50 , Viabilidade Microbiana , Dados de Sequência Molecular , Micélio/crescimento & desenvolvimento , Micélio/imunologia , Micélio/ultraestrutura , Micoses/sangue , Fragmentos de Peptídeos/química , Mapeamento de Peptídeos , Proteoma/química , Proteoma/imunologia , Proteoma/farmacologia , Proteômica , Pseudallescheria/crescimento & desenvolvimento , Pseudallescheria/imunologia , Pseudallescheria/ultraestrutura
6.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 17(4): 442-450, 2011. ilus
Artigo em Inglês | VETINDEX | ID: vti-7928

RESUMO

Two-dimensional gel electrophoresis (2DE) is an important tool for investigating the complexity of snake venom proteomes. Apart from applications based on whole proteome analysis, we suggest that 2DE can be used as an assay to guide the progress of protein purification. The aim of this study was to prove the feasibility of this concept by using it to purify rhodocetin from Calloselasma rhodostoma venom. Rhodocetin (α subunit) spot on the 2DE profile of C. rhodostoma venom was first identified and confirmed by mass spectrometry, with a molecular mass of 16 kDa and calculated pI of 5.16. Rhodocetin was subsequently purified by successive anion-exchange and gel filtration chromatography. Every peak from both chromatography profiles was collected and tested on 2DE. The presence of rhodocetin (α subunit) spot in the 2DE profile of the peak DP2 indicated the presence of the protein. The purified compound was used to spike the crude venom. A spiked spot with a 1.6-fold increase in intensity was observed and its position matched to that of rhodocetin (α subunit) on the 2DE profile. Together, these spots confirmed the identity of the purified compound as rhodocetin. Hence, our results have demonstrated the effectiveness of the concept we now term 2DE-guided purification.(AU)


Assuntos
Animais , Eletroforese em Gel Bidimensional/métodos , Eletroforese em Gel Bidimensional/veterinária , Proteoma/análise , Proteoma/farmacologia , Venenos de Serpentes
7.
Toxicon ; 47(3): 304-12, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16373076

RESUMO

Variation of venom proteome is relevant to basic research, to management of envenoming, and to studies on the evolution of poisonous snakes. In this study, we explored the venom proteomes of eighteen Bothrops jararaca specimens of a single litter born and raised in laboratory. Using electrophoretic techniques and various protocols for measuring the proteolytic activities of these venoms we have detected individual variability and highlighted sex-specific proteomic similarities and differences among sibling snakes. SDS-polyacrylamide gel electrophoresis under non-reducing conditions showed protein bands of approximately 100 kDa specific of male venoms. 2D-electrophoresis showed regions with varying spot complexity between pooled female and male venoms as well as spots that were gender specific. Gelatin zymography showed that female venoms contained proteinases of approximately 25 kDa absent from male venoms. Female venoms were more active than male venoms in degrading fibrinogen whereas on fibrin no significant differences were detected. Among various chromogenic peptide substrates tested, male venoms showed higher amidolytic activity than female venoms on D-Val-Leu-Lys-pNA and D-Phe-Pip-Arg-pNA. Taken together, these results show sex-based differences in the venom proteome of sibling snakes of a single litter raised under controlled conditions which seem to be genetically inherited and imposed by evolutionary forces.


Assuntos
Bothrops , Venenos de Crotalídeos/química , Proteoma/química , Amidas/metabolismo , Animais , Coagulação Sanguínea/efeitos dos fármacos , Bothrops/genética , Caseínas/metabolismo , Tamanho da Ninhada , Venenos de Crotalídeos/genética , Venenos de Crotalídeos/farmacologia , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Feminino , Fibrinogênio/metabolismo , Gelatina/metabolismo , Humanos , Masculino , Proteoma/genética , Proteoma/farmacologia , Fatores Sexuais
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