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1.
Toxins (Basel) ; 10(12)2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30487389

RESUMO

Snake venom serine proteases (SVSPs) are enzymes that are capable of interfering in various parts of the blood coagulation cascade, which makes them interesting candidates for the development of new therapeutic drugs. Herein, we isolated and characterized Moojase, a potent coagulant enzyme from Bothrops moojeni snake venom. The toxin was isolated from the crude venom using a two-step chromatographic procedure. Moojase is a glycoprotein with N-linked glycans, molecular mass of 30.3 kDa and acidic character (pI 5.80⁻6.88). Sequencing of Moojase indicated that it is an isoform of Batroxobin. Moojase was able to clot platelet-poor plasma and fibrinogen solutions in a dose-dependent manner, indicating thrombin-like properties. Moojase also rapidly induced the proteolysis of the Aα chains of human fibrinogen, followed by the degradation of the Bß chains after extended periods of incubation, and these effects were inhibited by PMSF, SDS and DTT, but not by benzamidine or EDTA. RP-HPLC analysis of its fibrinogenolysis confirmed the main generation of fibrinopeptide A. Moojase also induced the fibrinolysis of fibrin clots formed in vitro, and the aggregation of washed platelets, as well as significant amidolytic activity on substrates for thrombin, plasma kallikrein, factor Xia, and factor XIIa. Furthermore, thermofluor analyses and the esterase activity of Moojase demonstrated its very high stability at different pH buffers and temperatures. Thus, studies such as this for Moojase should increase knowledge on SVSPs, allowing their bioprospection as valuable prototypes in the development of new drugs, or as biotechnological tools.


Assuntos
Proteínas de Répteis , Serina Proteases , Venenos de Serpentes/enzimologia , Adulto , Animais , Coagulação Sanguínea/efeitos dos fármacos , Bothrops , Estabilidade Enzimática , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Proteínas de Répteis/química , Proteínas de Répteis/isolamento & purificação , Proteínas de Répteis/farmacologia , Serina Proteases/química , Serina Proteases/isolamento & purificação , Serina Proteases/farmacologia , Adulto Jovem
2.
J Proteome Res ; 17(11): 3941-3958, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30270628

RESUMO

Snake venoms are complex mixtures mainly composed of proteins and small peptides. Crotoxin is one of the most studied components from Crotalus venoms, but many other components are less known due to their low abundance. The venome of Crotalus durissus terrificus, the most lethal Brazilian snake, was investigated by combining its venom gland transcriptome and proteome to create a holistic database of venom compounds unraveling novel toxins. We constructed a cDNA library from C. d. terrificus venom gland using the Illumina platform and investigated its venom proteome through high resolution liquid chromotography-tandem mass spectrometry. After integrating data from both data sets, more than 30 venom components classes were identified by the transcriptomic analysis and 15 of them were detected in the venom proteome. However, few of them (PLA2, SVMP, SVSP, and VEGF) were relatively abundant. Furthermore, only seven expressed transcripts contributed to ∼82% and ∼73% of the abundance in the transcriptome and proteome, respectively. Additionally, novel venom proteins are reported, and we highlight the importance of using different databases to perform the data integration and discuss the structure of the venom components-related transcripts identified. Concluding, this research paves the way for novel investigations and discovery of future pharmacological agents or targets in the antivenom therapy.


Assuntos
Venenos de Crotalídeos/química , Crotalus/fisiologia , Proteoma/isolamento & purificação , Transcriptoma , Sequência de Aminoácidos , Animais , Carboxipeptidases/genética , Carboxipeptidases/isolamento & purificação , Carboxipeptidases/metabolismo , Cromatografia Líquida/métodos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/isolamento & purificação , Fatores de Crescimento de Fibroblastos/metabolismo , Expressão Gênica , Biblioteca Gênica , Ontologia Genética , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/isolamento & purificação , Hialuronoglucosaminidase/metabolismo , Anotação de Sequência Molecular , Proteoma/genética , Proteoma/metabolismo , Alinhamento de Sequência , Análise de Sequência de RNA , Espectrometria de Massas em Tandem/métodos
3.
Toxins (Basel) ; 10(5)2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29701671

RESUMO

Venom composition varies across snakes from all taxonomic levels and is influenced by the snakes’ age, habitat, diet, and sexual dimorphism. The present study reports the first in-depth investigation of venom composition in male and female Bothrops moojeni (B. moojeni) snakes (BmooM and BmooF, respectively) through three proteomics approaches associated with functional, cytotoxic, and immunoreactivity characterization. Compared with BmooM venom, BmooF venom exhibited weaker hyaluronidase, metalloproteinase, and phospholipase activity; stronger recognition by anti-bothropic serum; 1.4-fold stronger cytotoxicity; and greater number of peptides. The increased L-amino acid oxidase expression probably accounted for the stronger immunoreactivity and cytotoxicity of BmooF venom. BmooF and BmooM venom shared only 19% peptides. Some venom components were gender-specific, such as phospholipases B, phospholipase inhibitor, and hyaluronidases in BmooM, and cysteine-rich secretory proteins in BmooF. In conclusion, we describe herein the first proteomics study of B. moojeni snake venom and an in-depth characterization of gender-specific differences in venom composition. Altogether, our findings not only stress the importance of considering the snake’s gender during antivenom production, but also help to identify new potential drugs and biotechnological tools.


Assuntos
Bothrops/metabolismo , Venenos de Crotalídeos/química , Peptídeos/metabolismo , Proteínas de Répteis/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Venenos de Crotalídeos/toxicidade , Feminino , Humanos , Hialuronoglucosaminidase/metabolismo , L-Aminoácido Oxidase/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Metaloproteases/metabolismo , Fosfolipases/metabolismo , Proteômica , Serina Proteases/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-29467797

RESUMO

BACKGROUND: Advancements in proteomics, including the technological improvement in instrumentation, have turned mass spectrometry into an indispensable tool in the study of venoms and toxins. In addition, the advance of nanoscale liquid chromatography coupled to nanoelectrospray mass spectrometry allows, due to its high sensitivity, the study of venoms from species previously left aside, such as ants. Ant venoms are a complex mixture of compounds used for defense, predation or communication purposes. The venom from Neoponera ants, a genus restricted to Neotropical regions, is known to have cytolytic, hemolytic, antimicrobial and insecticidal activities. Moreover, venoms from several Neoponera species have been compared and differences in their toxicity related to nesting habitat variation were reported. Therefore, the present study aimed to perform a deep peptidomic analysis of Neoponera villosa venom and a comparison of seasonal and nesting habitat variations using high-resolution mass spectrometry. METHODS: Specimens of N. villosa ants were captured in Panga Natural Reserve (Uberlândia, MG, Brazil) from arboreal and ground-dwelling nests during summer and winter time. The venom glands were dissected, pooled and disrupted by ultra-sonic waves. The venom collected from different habitats (arboreal and ground-dwelling) and different seasons (summer and winter) was injected into a nanoACQUITY ULPC hyphened to a Q-Exactive Orbitrap mass spectrometer. The raw data were analyzed using PEAKS 7. RESULTS: The results showed a molecular diversity of more than 500 peptides among these venoms, mostly in the mass range of 800-4000 Da. Mutations and post-translational modifications were described and differences among the venoms were observed. Part of the peptides matched with ponericins, a well-known antimicrobial peptide family. In addition, smaller fragments related to ponericins were also identified, suggesting that this class of antimicrobial peptide might undergo enzymatic cleavages. CONCLUSION: There are substantial differences among the venom of N. villosa ants collected in different seasons and from different nest habitats. The venom composition is affected by climate changes that influence prey availability and predator presence. Clearly, nano-LC-MS boosted the knowledge about ant venom, a rich source of unexplored and promising bioactive compounds.

5.
Appl Microbiol Biotechnol ; 102(7): 3145-3158, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29455388

RESUMO

In general, hyaluronidases have a broad potential application on medicine and esthetics fields. Hyaluronidases from animal venoms cleave hyaluronan present in the extracellular matrix, acting as spreading factors of toxins into the tissues of the victim. However, the in-depth characterization of hyaluronidase from animal venoms has been neglected due to its instability and low concentration in the venom, which hamper its isolation. Thus, heterologous expression of hyaluronidase acts as a biotechnological tool in the obtainment of enough amounts of the enzyme for structural and functional studies. Therefore, this study produced a recombinant hyaluronidase from Tityus serrulatus scorpion venom, designated as rTsHyal-1, in the Pichia pastoris system. Thus, a gene for TsHyal-1 (gb|KF623285.1) was synthesized and cloned into the pPICZαA vector (GenScript Corporation) for heterologous expression in P. pastoris. rTsHyal-1 was expressed in laboratorial scale in a buffered minimal medium containing methanol (BMM) for 96 h with daily addition of methanol. Expression of rTsHyal-1 resulted in a total protein yield of 0.266 mg/mL. rTsHyal-1 partially purified through cation exchange chromatography presented a specific activity of 1097 TRU/mg, against 838 TRU/mg for the final expressed material, representing a 1.31-fold purification. rTsHyal-1 has molecular mass of 49.5 kDa, and treatment with PNGase F and analysis by mass spectrometry (MALDI-TOF) indicated a potential N-glycosylation of 4.5 kDa. Additionally, de novo sequencing of rTsHyal-1, performed in MALDI-TOF and Q Exactive Orbitrap MS, resulted in 46.8% of protein sequence coverage. rTsHyal-1 presents the highest substrate specificity to hyaluronan followed by chondroitin-6-sulfate, chondroitin-4-sulfate, and dermatan sulfate and showed an optimum activity at pH 6.0 and 40 °C. These results validate the biotechnological process for the heterologous expression of rTsHyal-1. This is the first recombinant hyaluronidase from scorpion venoms expressed in the P. pastoris system with preserved enzyme activity.


Assuntos
Expressão Gênica , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Pichia/genética , Proteínas Recombinantes/genética , Venenos de Escorpião/enzimologia , Sequência de Aminoácidos , Animais , Ácido Hialurônico/metabolismo , Proteínas Recombinantes/metabolismo
6.
Peptides ; 80: 9-17, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26116782

RESUMO

Ts19 Fragment II (Ts19 Frag-II) was first isolated from the venom of the scorpion Tityus serrulatus (Ts). It is a protein presenting 49 amino acid residues, three disulfide bridges, Mr 5534Da and was classified as a new member of class (subfamily) 2 of the ß-KTxs, the second one described for Ts scorpion. The ß-KTx family is composed by two-domain peptides: N-terminal helical domain (NHD), with cytolytic activity, and a C-terminal CSαß domain (CCD), with Kv blocking activity. The extensive electrophysiological screening (16 Kv channels and 5 Nav channels) showed that Ts19 Frag-II presents a specific and significant blocking effect on Kv1.2 (IC50 value of 544±32nM). However, no cytolytic activity was observed with this toxin. We conclude that the absence of 9 amino acid residues from the N-terminal sequence (compared to Ts19 Frag-I) is responsible for the absence of cytolytic activity. In order to prove this hypothesis, we synthesized the peptide with these 9 amino acid residues, called Ts19 Frag-III. As expected, Ts19 Frag-III showed to be cytolytic and did not block the Kv1.2 channel. The post-translational modifications of Ts19 and its fragments (I-III) are also discussed here. A mechanism of post-translational processing (post-splitting) is suggested to explain Ts19 fragments production. In addition to the discovery of this new toxin, this report provides further evidence for the existence of several compounds in the scorpion venom contributing to the diversity of the venom arsenal.


Assuntos
Peptídeos/química , Peptídeos/farmacologia , Venenos de Escorpião/química , Animais , Eletrofisiologia/métodos , Eritrócitos/efeitos dos fármacos , Feminino , Canal de Potássio Kv1.2/antagonistas & inibidores , Camundongos , Oócitos/efeitos dos fármacos , Peptídeos/isolamento & purificação , Bloqueadores dos Canais de Potássio/química , Bloqueadores dos Canais de Potássio/farmacologia , Processamento de Proteína Pós-Traducional , Venenos de Escorpião/isolamento & purificação , Escorpiões/química , Canais de Sódio Disparados por Voltagem/metabolismo , Xenopus laevis
7.
Appl Microbiol Biotechnol ; 99(23): 9971-86, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26227411

RESUMO

Snake venom serine proteases (SVSPs) act primarily on plasma proteins related to blood clotting and are considered promising for the treatment of several hemostatic disorders. We report the heterologous expression of a serine protease from Crotalus durissus collilineatus, named collinein-1, in Pichia pastoris, as well as the enzymatic comparative characterization of the toxin in native and recombinant forms. The complementary DNA (cDNA) encoding collinein-1 was amplified from cDNA library of C. d. collilineatus venom gland and cloned into the pPICZαA vector. The recombinant plasmid was used to transform cells of KM71H P. pastoris. Heterologous expression was induced by methanol and yielded 56 mg of recombinant collinein-1 (rCollinein-1) per liter of culture. The native collinein-1 was purified from C. d. collilineatus venom, and its identity was confirmed by amino acid sequencing. The native and recombinant enzymes showed similar effects upon bovine fibrinogen by releasing preferentially fibrinopeptide A. Although both enzymes have induced plasma coagulation, native Colinein-1 has shown higher coagulant activity. The serine proteases were able to hydrolyze the chromogenic substrates S-2222, S-2238, and S2302. Both enzymes showed high stability on different pH and temperature, and their esterase activities were inhibited in the presence of Zn2+ and Cu2+. The serine proteases showed similar k cat/K m values in enzyme kinetics assays, suggesting no significant differences in efficiency of these proteins to hydrolyze the substrate. These results demonstrated that rCollinein-1 was expressed with functional integrity on the evaluated parameters. The success in producing a functionally active recombinant SVSP may generate perspectives to their future therapeutic applications.


Assuntos
Venenos de Crotalídeos/enzimologia , Crotalus , Serina Proteases/isolamento & purificação , Serina Proteases/metabolismo , Animais , Coagulação Sanguínea , Bovinos , Clonagem Molecular , Cobre/metabolismo , Inibidores Enzimáticos/metabolismo , Estabilidade Enzimática , Fibrinogênio/metabolismo , Fibrinopeptídeo A/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Serina Proteases/química , Serina Proteases/genética , Temperatura , Zinco/metabolismo
8.
J Proteomics ; 94: 413-22, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24157790

RESUMO

Despite the noxious effects inflicted by Dinoponera ant's envenomation, the information about the biological properties and composition of their venom is still very limited. Ants from the genus Dinoponera are believed to be the world's largest living ants with a body length of 3cm. Their occurrence is restricted to tropical areas of South America. In this work, we study the venom of the giant Dinoponera quadriceps ant collected in 4 different regions of Brazil. By using a combination of complementary mass spectrometric approaches, we aim at: (i) characterizing the venom composition of these ants; (ii) establishing a comparative analysis of the venom from four geographically different regions in Brazil. This approach demonstrates that ant venom is a copious source of new compounds. Several peptides were identified and selected for "de novo sequencing". Since most of the new peptides showed similarities with antimicrobial peptides (AMPs), antimicrobial assays were performed with the purpose of evaluating their activity. In regard to the comparative study of the four regions, we observed not only major differences in the venom compositions, but also that the venoms collected in closest areas are more similar than the ones collected in distant regions. These observations seem to highlight an adaption of the ant venoms to the local environment. Concerning the biological assays, the peptides called Dq-3162 and Da-3177 showed a wide-ranging antimicrobial activity. The characterization of new AMPs with a broad spectrum of activity and different scaffolds may aid scientists to design new therapeutic agents and understand the mechanisms of those peptides to interact with microbial membranes. The results obtained betoken the biotechnological potential of ant's venom. BIOLOGICAL SIGNIFICANCE: For the first time this manuscript describes an extensive proteomics characterization of the D. quadriceps venom. In addition this study reports the variation in venom composition of primitive ants from 4 geographically different areas of Brazil. The results reveal the presence of ~335 compounds for each venom/area and inter-colony variations were observed. 16 new peptides were characterized and 2 of them were synthesized and biologically assayed. These findings highlight the considerable and still unexplored diversity of ant's venom which could be used as valuable research tools in different areas of knowledge.


Assuntos
Venenos de Formiga/química , Proteínas de Insetos/química , Peptídeos/química , Animais , Formigas , Brasil
9.
FEBS J ; 280(19): 4839-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23895459

RESUMO

Sea anemone venoms have become a rich source of peptide toxins which are invaluable tools for studying the structure and functions of ion channels. In this work, BcsTx3, a toxin found in the venom of a Bunodosoma caissarum (population captured at the Saint Peter and Saint Paul Archipelago, Brazil) was purified and biochemically and pharmacologically characterized. The pharmacological effects were studied on 12 different subtypes of voltage-gated potassium channels (K(V)1.1-K(V)1.6; K(V)2.1; K(V)3.1; K(V)4.2; K(V)4.3; hERG and Shaker IR) and three cloned voltage-gated sodium channel isoforms (Na(V)1.2, Na(V)1.4 and BgNa(V)1.1) expressed in Xenopus laevis oocytes. BcsTx3 shows a high affinity for Drosophila Shaker IR channels over rKv1.2, hKv1.3 and rKv1.6, and is not active on NaV channels. Biochemical characterization reveals that BcsTx3 is a 50 amino acid peptide crosslinked by four disulfide bridges, and sequence comparison allowed BcsTx3 to be classified as a novel type of sea anemone toxin acting on K(V) channels. Moreover, putative toxins homologous to BcsTx3 from two additional actiniarian species suggest an ancient origin of this newly discovered toxin family.


Assuntos
Venenos de Cnidários/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , Animais , Eletrofisiologia
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