RESUMO
In previous works, we identified a RNA-binding protein in presynaptic terminal of squid neurons, which is likely involved in local mRNA processing. Evidences indicate this strongly basic protein, called p65, is an SDS-stable dimer protein composed of ~ 37 kDa hnRNPA/B-like subunits. The function of p65 in presynaptic regions is not well understood. In this work, we showed p65 and its subunit p37 are concentrated in RNA-enriched regions in synaptosomes. We performed in vitro binding studies with a recombinant protein and showed its propensity to selectively bind actin mRNA at the squid presynaptic terminal. Biochemical analysis using lysed synaptosomes suggested RNA integrity may affect p65 and p37 functions. Mass spectrometry analysis of oligo(dT) pull down indicated squid hnRNPA1, hnRNPA1-like 2, hnRNPA3 and ELAV-like proteins as candidates to interact with p65 and p37 forming a ribonucleoprotein complex, suggesting a role of squid hnRNPA/B-like proteins in site-specific RNA processing.
Assuntos
Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Neurônios/metabolismo , Lobo Óptico de Animais não Mamíferos/metabolismo , Terminações Pré-Sinápticas/metabolismo , Animais , Decapodiformes , Ribonucleoproteínas Nucleares Heterogêneas/genética , Sinaptossomos/metabolismoRESUMO
Traditionally, chymosin has been used for milk-clotting, but this naturally occurring enzyme is in short supply and its use has raised religious and ethical concerns. Because milk-clotting peptidases are a promising substitute for chymosin in cheese preparation, there is a need to find and test the specificity of these enzymes. Here, we evaluated the milk-clotting properties of an aspartic peptidase secreted by Rhizopus microsporus. The molecular mass of this enzyme was estimated at 36 kDa and Pepstatin A was determined to be an inhibitor. Optimal activity occurred at a pH of 5.5 and a temperature range of 50-60 °C, but the peptidase was stable in the pH range of 4-7 and a temperature as low as 45 °C. Proteolytic activity was significantly reduced in the presence of Cu2+ and Al3+. When enzyme substrates based on FRET were used, this peptidase exhibited the highest catalytic efficiency for Abz-KNRSSKQ-EDDnp (4,644 ± 155 mM-1.s-1), Abz-KLRSSNQ-EDDnp (3,514 ± 130 mM-1.s-1), and Abz-KLRQSKQ-EDDnp (3,068 ± 386 mM-1.s-1). This study presents a promising peptidase for use in cheese making, due to its high stability in the presence of Ca2+ and broad pH range of 4-7, in addition to its ability to efficiently clot milk.
Assuntos
Ácido Aspártico Proteases/química , Proteínas Fúngicas/química , Leite/química , Rhizopus/enzimologia , Animais , Bovinos , Concentração de Íons de HidrogênioRESUMO
The fungal genus Pyrenochaetopsis has received particular attention because of its different lifestyles, such as numerous plant pathogenic, saprophytic, and endophytic species. Its ability to infect plant cells relies heavily upon secreted peptidases. Here, we investigated the biochemical properties and catalytic specificity of a new serine peptidase secreted by the filamentous fungus Pyrenochaetopsis sp. We found that while this neutral serine peptidase displayed optimal activity at a pH of 7.0 and temperature of 45 °C, it tolerated a wide range of pH conditions and temperatures lower than 45 °C. Its peptidase activity was depressed by some metallic ions (such as aluminum, cobalt, and copper (II) chloride) and enhanced by others (such as sodium, lithium, magnesium, potassium, calcium, and manganese). Lastly, the enzyme showed the greatest specificity for non-polar amino acids, particularly leucine and isoleucine, and moderate specificity for basic and neutral polar amino acids. It displayed the least specificity for acidic residues.
Assuntos
Ascomicetos/enzimologia , Biocatálise , Serina Proteases/química , Serina Proteases/metabolismo , Inibidores Enzimáticos/farmacologia , Guanidina/farmacologia , Metais/farmacologia , Inibidores de Serina Proteinase/farmacologia , Especificidade por Substrato , Tensoativos/farmacologia , Temperatura , Ureia/farmacologiaRESUMO
Visceral obesity is frequently associated with the development of type 2 diabetes (T2D), a highly prevalent chronic disease that features insulin resistance and pancreatic ß-cell dysfunction as important hallmarks. Recent evidence indicates that the chronic, low-grade inflammation commonly associated with visceral obesity plays a major role connecting the excessive visceral fat deposition with the development of insulin resistance and pancreatic ß-cell dysfunction. Herein, we review the mechanisms by which nutrients modulate obesity-associated inflammation.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Nutrientes , Animais , Ácidos Graxos Monoinsaturados/metabolismo , Humanos , Inflamação/complicações , Insulina/metabolismo , Gordura Intra-Abdominal/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Doenças Metabólicas , Camundongos , Obesidade/metabolismo , Transdução de SinaisRESUMO
Programming of hypothalamic functions regulating energy homeostasis may play a role in intrauterine growth restriction (IUGR)-induced adulthood obesity. The present study investigated the effects of IUGR on the hypothalamus proteome and metabolome of adult rats submitted to 50% protein-energy restriction throughout pregnancy. Proteomic and metabolomic analyzes were performed by data independent acquisition mass spectrometry and multiple reaction monitoring, respectively. At age 4 months, the restricted rats showed elevated adiposity, increased leptin and signs of insulin resistance. 1356 proteins were identified and 348 quantified while 127 metabolites were quantified. The restricted hypothalamus showed down-regulation of 36 proteins and 5 metabolites and up-regulation of 21 proteins and 9 metabolites. Integrated pathway analysis of the proteomics and metabolomics data indicated impairment of hypothalamic glucose metabolism, increased flux through the hexosamine pathway, deregulation of TCA cycle and the respiratory chain, and alterations in glutathione metabolism. The data suggest IUGR modulation of energy metabolism and redox homeostasis in the hypothalamus of male adult rats. The present results indicated deleterious consequences of IUGR on hypothalamic pathways involved in pivotal physiological functions. These results provide guidance for future mechanistic studies assessing the role of intrauterine malnutrition in the development of metabolic diseases later in life.
Assuntos
Retardo do Crescimento Fetal/metabolismo , Metabolômica , Obesidade/metabolismo , Biossíntese de Proteínas/genética , Proteômica , Animais , Animais Recém-Nascidos , Metabolismo Energético/genética , Feminino , Retardo do Crescimento Fetal/genética , Hipotálamo/metabolismo , Obesidade/genética , Obesidade/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , RatosRESUMO
For a long time, proteolytic enzymes have been employed as key tools of industrial processes, especially in the dairy industry. In the present work, we used Phanerochaete chrysosporium for biochemical characterization and analysis of catalytic specificity of an aspartic peptidase. Our results revealed an aspartic peptidase with molecular mass â¼38kDa, maximal activity at pH 4.5 and 50°C, and stability above 80% in the pH range of 3-8 and temperature up to 55°C for 1h. In a milk-clotting assay, this peptidase showed maximal milk clotting activity at 60-65°C and maintenance of enzymatic activity above 80% in the presence of 20mM CaCl2. In a specificity assay, we observed stronger restriction of catalysis at the S1 subsite, with a preference for lysine, arginine, leucine, tyrosine, and phenylalanine residues. The restricted proteolysis and milk-clotting potential are attractive properties for the use in cheese production.
Assuntos
Ácido Aspártico Proteases/metabolismo , Queijo/microbiologia , Indústria de Processamento de Alimentos , Leite/microbiologia , Phanerochaete/enzimologia , Animais , Proteínas Fúngicas/metabolismo , TemperaturaRESUMO
Cysteine-rich secretory proteins (CRISPs) are commonly described as part of the protein content of snake venoms, nevertheless, so far, little is known about their biological targets and functions. Our study describes the isolation and characterization of Bj-CRP, the first CRISP isolated from Bothrops jararaca snake venom, also aiming at the identification of possible targets for its actions. Bj-CRP was purified using three chromatographic steps (Sephacryl S-200, Source 15Q and C18) and showed to be an acidic protein of 24.6kDa with high sequence identity to other snake venom CRISPs. This CRISP was devoid of proteolytic, hemorrhagic or coagulant activities, and it did not affect the currents from 13 voltage-gated potassium channel isoforms. Conversely, Bj-CRP induced inflammatory responses characterized by increase of leukocytes, mainly neutrophils, after 1 and 4h of its injection in the peritoneal cavity of mice, also stimulating the production of IL-6. Bj-CRP also acted on the human complement system, modulating some of the activation pathways and acting directly on important components (C3 and C4), thus inducing the generation of anaphylatoxins (C3a, C4a and C5a). Therefore, our results for Bj-CRP open up prospects for better understanding this class of toxins and its biological actions.
Assuntos
Bothrops , Venenos de Crotalídeos/química , Peptídeos/isolamento & purificação , Sequência de Aminoácidos , Anafilatoxinas/biossíntese , Anafilatoxinas/imunologia , Animais , Coagulação Sanguínea/efeitos dos fármacos , Células Cultivadas , Ativação do Complemento/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Hemorragia/induzido quimicamente , Humanos , Técnicas In Vitro , Masculino , Camundongos Endogâmicos C57BL , Peso Molecular , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Técnicas de Patch-Clamp , Peptídeos/farmacologia , Peptídeos/toxicidade , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , Proteínas de Répteis/isolamento & purificação , Proteínas de Répteis/farmacologia , Proteínas de Répteis/toxicidade , Venenos de Víboras/isolamento & purificação , Venenos de Víboras/farmacologia , Venenos de Víboras/toxicidade , Xenopus laevisRESUMO
Peptidases are enzymes that catalyze the rupture of peptide bonds. Catalytic specificity studies of these enzymes have illuminated their modes of action and preferred hydrolysis targets. We describe the biochemical characteristics and catalytic specificity of a lysine-dependent peptidase secreted by the basidiomycete fungus Phanerochaete chrysosporium. We attained 5.7-fold purification of a â¼23-kDa neutral peptidase using size-exclusion (Sephadex G-50 resin) and ion-exchange (Source 15S resin) chromatography. Using the Fluorescence Resonance Energy Transfer substrate Abz-KLRSSKQ-EDDnp, we detected maximal activity at pH 7.0 and 45-55°C. The peptidase retained â¼80% of its enzymatic activity for a wide range of conditions (pH 4-9; temperatures up to 50°C for 1h). The peptidase activity was lowered by the ionic surfactants, sodium dodecyl sulfate and cetyltrimethylammonium bromide; the reducing agent, dithiothreitol; the chaotrope, guanidine; copper (II) ion; and the cysteine peptidase-specific inhibitors, iodoacetic acid and N-ethylmaleimide. The peptidase preferred the basic amino acids K and R and high selectivity on S'1 subsite, exhibiting a condition of lysine-dependence to catalysis on anchoring of this subsite.
Assuntos
Cisteína Proteases/química , Proteínas Fúngicas/química , Sequência de Aminoácidos , Biocatálise , Cisteína Proteases/isolamento & purificação , Inibidores de Cisteína Proteinase/química , Estabilidade Enzimática , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Lisina/química , Phanerochaete/enzimologia , Proteólise , Especificidade por SubstratoRESUMO
Laccase production by Pycnoporus sanguineus RP15 grown in wheat bran and corncob under solid-state fermentation was optimized by response surface methodology using a Central Composite Rotational Design. A laccase (Lacps1) was purified and characterized and the potential of the pure Lacps1 and the crude culture extract for synthetic dye decolorization was evaluated. At optimal conditions (eight days, 26 °C, 18% (w/w) milled corncob, 0.8% (w/w) NH4Cl and 50 mmol·L(-1) CuSO4, initial moisture 4.1 mL·g(-1)), the laccase activity reached 138.6 ± 13.2 U·g(-1). Lacps1 was a monomeric glycoprotein (67 kDa, 24% carbohydrate). Optimum pH and temperature for the oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonate) (ABTS) were 4.4 and 74.4 °C, respectively. Lacps1 was stable at pH 3.0-8.0, and after two hours at 55-60 °C, presenting high redox potential (0.747 V vs. NHE). ABTS was oxidized with an apparent affinity constant of 147.0 ± 6.4 µmol·L(-1), maximum velocity of 413.4 ± 21.2 U·mg(-1) and catalytic efficiency of 3140.1 ± 149.6 L·mmol(-1)·s(-1). The maximum decolorization percentages of bromophenol blue (BPB), remazol brilliant blue R and reactive blue 4 (RB4), at 25 or 40 °C without redox mediators, reached 90%, 80% and 60%, respectively, using either pure Lacps1 or the crude extract. This is the first study of the decolorization of BPB and RB4 by a P. sanguineus laccase. The data suggested good potential for treatment of industrial dye-containing effluents.
Assuntos
Corantes/química , Proteínas Fúngicas/metabolismo , Lacase/metabolismo , Pycnoporus/enzimologia , Benzotiazóis/química , Fermentação , Oxirredução , Pycnoporus/crescimento & desenvolvimento , Ácidos Sulfônicos/químicaRESUMO
In this study, we detail the specificity of an aspartic peptidase from Rhizomucor miehei and evaluate the effects of this peptidase on clotting milk using the peptide sequence of k-casein (Abz-LSFMAIQ-EDDnp) and milk powder. Molecular mass of the peptidase was estimated at 37 kDa, and optimum activity was achieved at pH 5.5 and 55 °C. The peptidase was stable at pH values ranging from 3 to 5 and temperatures of up 45 °C for 60 min. Dramatic reductions in proteolytic activity were observed with exposure to sodium dodecyl sulfate, and aluminum and copper (II) chloride. Peptidase was inhibited by pepstatin A, and mass spectrometry analysis identified four peptide fragments (TWSISYGDGSSASGILAK, ASNGGGGEYIFGGYDSTK, GSLTTVPIDNSR, and GWWGITVDRA), similar to rhizopuspepsin. The analysis of catalytic specificity showed that the coagulant activity of the peptidase was higher than the proteolytic activity and that there was a preference for aromatic, basic, and nonpolar amino acids, particularly methionine, with specific cleavage of the peptide bond between phenylalanine and methionine. Thus, this peptidase may function as an important alternative enzyme in milk clotting during the preparation of cheese.
Assuntos
Ácido Aspártico Proteases/química , Ácido Aspártico Proteases/metabolismo , Leite/química , Rhizomucor/enzimologia , Sequência de Aminoácidos , Animais , Ácido Aspártico Endopeptidases/química , Biocatálise , Caseínas/química , Queijo , Concentração de Íons de Hidrogênio , Cinética , Especificidade por Substrato , TemperaturaRESUMO
Exposure to high fluoride levels during amelogenesis causes enamel fluorosis. This study aimed to determine and compare the amino acid sequences in the enamel of fluorotic and control teeth. This investigation included enamel samples obtained from erupted and non-erupted third molars with either TF grade 4-6 (n=7) fluorosis or no sign of fluorosis (controls, n=7). The samples were kept frozen at -20 °C until protein extraction. Samples were etched and processed with a cocktail of proteinase inhibitors and immediately analyzed. Matrix Assisted Laser Desorption/Ionization-Time-Of-Flight/Time-of-Flight Mass Spectrometry (MALDI-TOF/TOF) followed by MASCOT search aided the peptides analysis. The more abundant peptides bore the N-terminal amelogenin sequences WYQSIRPPYP (which is specific for the X-encoded amelogenin) and MPLPPHPGHPGYINF (which does not show sexual dimorphism) were not different in control or fluorotic enamel. There was no missing proteolytic cleavage in the fluorotic samples, which suggested that the increased amount of protein described in fluorotic enamel did not stem from the decreased ability of proteinases to cleave the proteins in humans. This study showed how to successfully obtain peptide from superficial enamel. A relatively low number of teeth was sufficient to provide good data on the actual peptides found in mature enamel.
Assuntos
Fluorose Dentária/metabolismo , Peptídeos/química , Sequência de Aminoácidos , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Abstract Exposure to high fluoride levels during amelogenesis causes enamel fluorosis. This study aimed to determine and compare the amino acid sequences in the enamel of fluorotic and control teeth. This investigation included enamel samples obtained from erupted and non-erupted third molars with either TF grade 4-6 (n=7) fluorosis or no sign of fluorosis (controls, n=7). The samples were kept frozen at -20 °C until protein extraction. Samples were etched and processed with a cocktail of proteinase inhibitors and immediately analyzed. Matrix Assisted Laser Desorption/Ionization-Time-Of-Flight/Time-of-Flight Mass Spectrometry (MALDI-TOF/TOF) followed by MASCOT search aided the peptides analysis. The more abundant peptides bore the N-terminal amelogenin sequences WYQSIRPPYP (which is specific for the X-encoded amelogenin) and MPLPPHPGHPGYINF (which does not show sexual dimorphism) were not different in control or fluorotic enamel. There was no missing proteolytic cleavage in the fluorotic samples, which suggested that the increased amount of protein described in fluorotic enamel did not stem from the decreased ability of proteinases to cleave the proteins in humans. This study showed how to successfully obtain peptide from superficial enamel. A relatively low number of teeth was sufficient to provide good data on the actual peptides found in mature enamel.
Resumo Exposição a altos níveis de flúor durante a amelogênese causa fluorose no esmalte. Este estudo tem como objetivo determinar e comparar as sequências de aminoácidos presentes no esmalte de dentes controles e fluoróticos. A investigação incluiu amostras de esmalte obtidas de terceiros molares erupcionados e não erupcionados, ambas ou com grau de fluorose TF 4-6 (n=7) ou sem sinais de fluorose (controles, n=7), congelados a -20 oC até a extração das proteínas. As amostras sofreram ataque ácido e foram processadas utilizando um coquetel de inibidores de proteinases, sendo imediatamente analisadas. MALDI-TOF/TOF seguido pela pesquisa com MASCOT foram utilizados para a análise dos peptídeos. Os peptídeos mais abundantes foram das amelogeninas com sequências N-terminal WYQSIRPPYP (que é codificada especificamente pela amelogenina X) e MPLPPHPGHPGYINF (que não apresenta dimorfismo sexual algum), não havendo diferenças entre dentes fluoróticos e controles. Nenhuma alteração na proteólise ocorreu nas amostras fluoróticas, o que sugere que o aumento na quantidade de proteínas existentes nas amostras fluoróticas não está correlacionada a habilidade das proteinases em clivar as proteínas em humanos. Este estudo mostrou como extrair com sucesso peptídeos do esmalte superficial. Um número relativamente baixo de dentes foram suficientes para se obter ótimos dados a respeito de peptídeos encontrados no esmalte maduro.
Assuntos
Humanos , Fluorose Dentária/metabolismo , Peptídeos/química , Sequência de Aminoácidos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Coagulopathies following snakebite are triggered by pro-coagulant venom toxins, in which metalloproteases play a major role in envenomation-induced coagulation disorders by acting on coagulation cascade, platelet function and fibrinolysis. Considering this relevance, here we describe the isolation and biochemical characterization of moojenactivase (MooA), a metalloprotease from Bothrops moojeni snake venom, and investigate its involvement in hemostasis in vitro. MooA is a glycoprotein of 85,746.22 Da, member of the PIIId group of snake venom metalloproteases, composed of three linked disulfide-bonded chains: an N-glycosylated heavy chain, and two light chains. The venom protease induced human plasma clotting in vitro by activating on both blood coagulation factors II (prothrombin) and X, which in turn generated α-thrombin and factor Xa, respectively. Additionally, MooA induced expression of tissue factor (TF) on the membrane surface of peripheral blood mononuclear cells (PBMC), which led these cells to adopt pro-coagulant characteristics. MooA was also shown to be involved with production of the inflammatory mediators TNF-α, IL-8 and MCP-1, suggesting an association between MooA pro-inflammatory stimulation of PBMC and TF up-regulation. We also observed aggregation of washed platelets when in presence of MooA; however, the protease had no effect on fibrinolysis. Our findings show that MooA is a novel hemostatically active metalloprotease, which may lead to the development of coagulopathies during B. moojeni envenomation. Moreover, the metalloprotease may contribute to the development of new diagnostic tools and pharmacological approaches applied to hemostatic disorders.
Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Bothrops/metabolismo , Coagulantes/farmacologia , Venenos de Crotalídeos/enzimologia , Fator Xa/metabolismo , Leucócitos/efeitos dos fármacos , Metaloendopeptidases/farmacologia , Metaloproteases/farmacologia , Protrombina/metabolismo , Tromboplastina/metabolismo , Adulto , Sequência de Aminoácidos , Animais , Coagulantes/isolamento & purificação , Venenos de Crotalídeos/isolamento & purificação , Venenos de Crotalídeos/farmacologia , Estabilidade Enzimática , Feminino , Humanos , Concentração de Íons de Hidrogênio , Mediadores da Inflamação/metabolismo , Cinética , Leucócitos/metabolismo , Masculino , Metaloendopeptidases/isolamento & purificação , Metaloproteases/isolamento & purificação , Pessoa de Meia-Idade , Temperatura , Adulto JovemRESUMO
Phospholipase A2 inhibitors (PLIs) are important targets in the search and development of new drugs. This study aimed at evaluating the potential of an alpha-type phospholipase A2 inhibitor from Bothrops alternatus (Rhinocerophis alternatus) snake in its recombinant form (rBaltMIP) to complement the conventional antivenom therapy. Biochemical experiments showed that rBaltMIP presented pI 5.8 and molecular masses of â¼21 kDa by SDS-PAGE and 19.57 kDa by MALDI/TOF MS. After tryptic peptides sequencing, the results were compared with other PLIs available in databases, showing 100% identity between rBaltMIP and its native inhibitor BaltMIP and from 92% to 96% identity with other inhibitors. Myotoxic activities of BthTX-I and BthTX-II toxins were measured via plasma CK levels, showing myotoxic effective concentrations (EC50) of 0.1256 µg/µL and 0.6183 µg/µL, respectively. rBaltMIP neutralized the myotoxicity caused by these two toxins up to 65%, without promoting primary antibody response against itself. Nevertheless, this recombinant PLI was immunogenic when standard immunization protocol with Freud's adjuvant was used. In paw edema assays, EC50 of 0.02581 µg/µL and 0.02810 µg/µL, respectively, were observed with edema reductions of up to 40% by rBaltMIP, suggesting its use as an additional antivenom. In addition, myotoxicity neutralization experiments with the myotoxin BthTX-I showed that rBaltMIP was more effective in inhibiting muscle damage than the conventional antivenom. Thus, considering the severity of envenomations due to Bothrops alternatus (Rhinocerophis alternatus) and the low neutralization of their local effects (such as myotoxicity) by the current antivenoms, rBaltMIP is a promising molecule for the development of novel therapeutic strategies for clinical applications.
Assuntos
Antivenenos/uso terapêutico , Bothrops , Inibidores de Fosfolipase A2/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Mordeduras de Serpentes/tratamento farmacológico , Animais , Antivenenos/química , Camundongos , Camundongos Endogâmicos BALB C , Inibidores de Fosfolipase A2/isolamento & purificação , Proteínas Recombinantes/isolamento & purificação , Proteínas de Répteis , Mordeduras de Serpentes/patologia , Testes de ToxicidadeRESUMO
BACKGROUND: Leishmaniasis is a complex disease in which clinical outcome depends on factors such as parasite species, host genetics and immunity and vector species. In Brazil, Leishmania (Viannia) braziliensis is a major etiological agent of cutaneous (CL) and mucosal leishmaniasis (MCL), a disfiguring form of the disease, which occurs in ~10% of L. braziliensis-infected patients. Thus, clinical isolates from patients with CL and MCL may be a relevant source of information to uncover parasite factors contributing to pathogenesis. In this study, we investigated two pairs of L. (V.) braziliensis isolates from mucosal (LbrM) and cutaneous (LbrC) sites of the same patient to identify factors distinguishing parasites that migrate from those that remain at the primary site of infection. METHODOLOGY/PRINCIPAL FINDINGS: We observed no major genomic divergences among the clinical isolates by molecular karyotype and genomic sequencing. RT-PCR revealed that the isolates lacked Leishmania RNA virus (LRV). However, the isolates exhibited distinct in vivo pathogenesis in BALB/c mice; the LbrC isolates were more virulent than the LbrM isolates. Metabolomic analysis revealed significantly increased levels of 14 metabolites in LbrC parasites and 31 metabolites in LbrM parasites that were mainly related to inflammation and chemotaxis. A proteome comparative analysis revealed the overexpression of LbrPGF2S (prostaglandin f2-alpha synthase) and HSP70 in both LbrC isolates. Overexpression of LbrPGF2S in LbrC and LbrM promastigotes led to an increase in infected macrophages and the number of amastigotes per cell at 24-48 h post-infection (p.i.). CONCLUSIONS/SIGNIFICANCE: Despite sharing high similarity at the genome structure and ploidy levels, the parasites exhibited divergent expressed genomes. The proteome and metabolome results indicated differential profiles between the cutaneous and mucosal isolates, primarily related to inflammation and chemotaxis. BALB/c infection revealed that the cutaneous isolates were more virulent than the mucosal parasites. Furthermore, our data suggest that the LbrPGF2S protein is a candidate to contribute to parasite virulence profiles in the mammalian host.
Assuntos
Leishmania braziliensis/genética , Leishmania braziliensis/isolamento & purificação , Leishmaniose Mucocutânea/microbiologia , Metaboloma , Mucosa/microbiologia , Proteoma , Pele/microbiologia , Animais , Brasil , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Leishmaniose Mucocutânea/patologia , Camundongos Endogâmicos BALB C , Mucosa/patologia , Pele/patologiaRESUMO
Proteases hydrolyze polypeptides to release peptides and/or amino acids. This subclass of enzymes is among those with the most sales worldwide, particularly those produced by microorganisms. Proteases may be applied in the several industries, including the food industry, leather, detergents, and bioremediation. Myceliophthora thermophila protease was produced by a submerged bioprocess and then purified 185-fold by anion exchange and hydrophobic chromatography with a 37% yield. The molecular mass was estimated at 36.2 kDa, and mass spectrometry identified two sequences: GVVANMSLGGSYSASINNAAAALVR and STGNAAITGVPSGTTNR. The isolated protein was characterized biochemically, showed an optimum pH of 6.5 and optimum temperature of 45 °C, and stability at wide range of pH and temperatures and in the presence of reducing agents and some surfactants. Kinetic assays for this enzyme showed a greater catalytic efficiency when the substrate had alanine at position P'2. The protease presented characteristics that may be of interest to many industrial areas.
Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Sordariales/enzimologia , Sequência de Aminoácidos , Caseínas/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peptídeo Hidrolases/isolamento & purificação , TemperaturaRESUMO
Phospholipases A2 (PLA2s) are enzymes responsible for inflammatory effects, edema formation, myotoxicity, neurotoxicity and other manifestations from envenoming. In this paper we report the isolation and biochemical characterization of Lmr-PLA2, the first acidic PLA2 found in Lachesis muta rhombeata venom. Furthermore, this study compared biological effects of Lmr-PLA2 and crotoxin B (CB), a PLA2 from Crotalus durissus terrificus venom. Lmr-PLA2 was isolated by molecular exclusion and reversed phase chromatography. The purified enzyme showed a molecular mass of 13,975 Da, pI of 5.46 and its partial amino acid sequence showed a high identity with PLA2s already described in the literature. In addition, this enzyme possesses the residue D49 in its amino acid sequence, indicating that it is a catalytically active PLA2. Lmr-PLA2 presented high phospholipase activity and was able to inhibit platelet aggregation. Studies of biochemical characterization of new PLA2s, as Lmr-PLA2, are relevant since they help to clarify the structure-function relationship of this important class of toxins.
Assuntos
Fosfolipases A2/química , Fosfolipases A2/isolamento & purificação , Proteínas de Répteis/química , Proteínas de Répteis/isolamento & purificação , Venenos de Víboras/química , Sequência de Aminoácidos , Animais , Creatina Quinase/análise , Creatina Quinase/metabolismo , Crotoxina/química , Edema/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Fragmentos de Peptídeos/análise , Fosfolipases A2/toxicidade , Agregação Plaquetária/efeitos dos fármacos , Proteínas de Répteis/toxicidade , Alinhamento de Sequência , ViperidaeRESUMO
Crotoxin is a neurotoxin from Crotalus durissus terrificus venom that shows immunomodulatory, anti-inflammatory, antimicrobial, antitumor and analgesic activities. Structurally, this toxin is a heterodimeric complex composed by a toxic basic PLA2 (Crotoxin B or CB) non-covalently linked to an atoxic non-enzymatic and acidic component (Crotapotin, Crotoxin A or CA). Several CA and CB isoforms have been isolated and characterized, showing that the crotoxin venom fraction is, in fact, a mixture of different molecules derived from the combination of distinct subunit isoforms. Intercro (IC) is a protein from the same snake venom which presents high similarity in primary structure to CB, indicating that it could be an another isoform of this toxin. In this work, we compare IC to the crotoxin complex (CA/CB) and/or CB in order to understand its functional aspects. The experiments with IC revealed that it is a new toxin with different biological activities from CB, keeping its catalytic activity but presenting low myotoxicity and absence of neurotoxic activity. The results also indicated that IC is structurally similar to CB isoforms, but probably it is not able to form a neurotoxic active complex with crotoxin A as observed for CB. Moreover, structural and phylogenetic data suggest that IC is a new toxin with possible toxic effects not related to the typical CB neurotoxin.
Assuntos
Venenos de Crotalídeos/metabolismo , Fosfolipases A2/metabolismo , Sequência de Aminoácidos , Animais , Venenos de Crotalídeos/química , Venenos de Crotalídeos/genética , Venenos de Crotalídeos/isolamento & purificação , Crotalus , Masculino , Camundongos , Modelos Moleculares , Fosfolipases A2/química , Fosfolipases A2/genética , Fosfolipases A2/isolamento & purificação , Filogenia , Alinhamento de Sequência , Venenos de Serpentes/metabolismoRESUMO
Bothrops pirajai snake venom was analyzed by a proteomic strategy. Proteins were separated by RP-HPLC, followed by SDS-PAGE, in-gel tryptic digestion, identification by MALDI-TOF/TOF mass spectrometry, and assignment to known protein families by similarity. Proteins belonging to six families were found in B. pirajai venom, including abundant PLA2s and metalloproteinases, with the remaining proteins distributed among l-amino acid oxidase, serine proteinase, disintegrin and lectin-like families. A P-I class metalloproteinase, named BpirMP, was isolated from this venom by three chromatographic steps. The enzyme has a molecular mass of 23.1kDa, as determined by mass spectrometry. Its proteolytic activity on azocasein was inhibited by chelating and reducing agents, with optimum activity at higher pH values and 37°C. BpirMP presented weak hemorrhagic activity, with an MHD of 50µg, and was able to hydrolyze basement membrane components in vivo and in vitro. The toxin cleaved both Aα and Bß chains of fibrinogen and was also able to degrade fibrin and blood clots in vitro. The primary sequence analysis indicates that BpirMP contains a zinc ligand motif and a CVM motif that is associated with a Met-turn structure. These results demonstrate that BpirMP is a zinc-dependent hemorrhagic metalloproteinase with fibrin(ogen)olytic and thrombolytic activities. BIOLOGICAL SIGNIFICANCE: This manuscript describes the diversity of protein components present in the venom of Bothops pirajai, a threatened snake species from northeastern Brazil, as well as the isolation and biochemical properties of a PI-SVMP. The results showed distinct mechanisms of action that should contribute in the elucidation of the differences in the hemorrhagic potential of SVMPs, allowing a better understanding of this class of enzymes and of the biology of Bothrops pirajai species.