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1.
Int J Biol Macromol ; 238: 124357, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37028634

RESUMEN

Animal venoms and their chemical compounds have aroused both empirical and scientific attention for ages. However, there has been a significant increase in scientific investigations in recent decades, allowing the production of various formulations that are helping in the development of many important tools for biotechnological, diagnostic, or therapeutic use, both in human and animal health, as well as in plants. Venoms are composed of biomolecules and inorganic compounds that may have physiological and pharmacological activities that are not related to their principal actions (prey immobilization, digestion, and defense). Snake venom toxins, mainly enzymatic and non-enzymatic proteins, and peptides have been identified as potential prototypes for new drugs and/or models for the development of pharmacologically active structural domains for the treatment of cancer, cardiovascular diseases, neurodegenerative and autoimmune diseases, pain, and infectious-parasitic diseases. This minireview aims to provide an overview of the biotechnological potential of animal venoms, with a focus on snakes, and to introduce the reader to the fascinating world of Applied Toxinology, where animal biodiversity can be used to develop therapeutic and diagnostic applications for humans.


Asunto(s)
Neoplasias , Venenos de Serpiente , Animales , Humanos , Venenos de Serpiente/química , Serpientes/metabolismo , Proteínas/química , Péptidos/farmacología , Neoplasias/tratamiento farmacológico
2.
Nat Rev Chem ; 6(7): 451-469, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35702592

RESUMEN

The fascination and fear of snakes dates back to time immemorial, with the first scientific treatise on snakebite envenoming, the Brooklyn Medical Papyrus, dating from ancient Egypt. Owing to their lethality, snakes have often been associated with images of perfidy, treachery and death. However, snakes did not always have such negative connotations. The curative capacity of venom has been known since antiquity, also making the snake a symbol of pharmacy and medicine. Today, there is renewed interest in pursuing snake-venom-based therapies. This Review focuses on the chemistry of snake venom and the potential for venom to be exploited for medicinal purposes in the development of drugs. The mixture of toxins that constitute snake venom is examined, focusing on the molecular structure, chemical reactivity and target recognition of the most bioactive toxins, from which bioactive drugs might be developed. The design and working mechanisms of snake-venom-derived drugs are illustrated, and the strategies by which toxins are transformed into therapeutics are analysed. Finally, the challenges in realizing the immense curative potential of snake venom are discussed, and chemical strategies by which a plethora of new drugs could be derived from snake venom are proposed.

4.
Nat Rev Chem ; 6(7): 451-469, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-37117308

RESUMEN

The fascination and fear of snakes dates back to time immemorial, with the first scientific treatise on snakebite envenoming, the Brooklyn Medical Papyrus, dating from ancient Egypt. Owing to their lethality, snakes have often been associated with images of perfidy, treachery and death. However, snakes did not always have such negative connotations. The curative capacity of venom has been known since antiquity, also making the snake a symbol of pharmacy and medicine. Today, there is renewed interest in pursuing snake-venom-based therapies. This Review focuses on the chemistry of snake venom and the potential for venom to be exploited for medicinal purposes in the development of drugs. The mixture of toxins that constitute snake venom is examined, focusing on the molecular structure, chemical reactivity and target recognition of the most bioactive toxins, from which bioactive drugs might be developed. The design and working mechanisms of snake-venom-derived drugs are illustrated, and the strategies by which toxins are transformed into therapeutics are analysed. Finally, the challenges in realizing the immense curative potential of snake venom are discussed, and chemical strategies by which a plethora of new drugs could be derived from snake venom are proposed.


Asunto(s)
Medicina , Mordeduras de Serpientes , Toxinas Biológicas , Animales , Venenos de Serpiente/química , Serpientes , Mordeduras de Serpientes/tratamiento farmacológico , Toxinas Biológicas/uso terapéutico
5.
J Proteomics ; 249: 104379, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-34534714

RESUMEN

We report the first proteomics analyses of the venoms of two poorly studied snakes, the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to South Pacific Costa Rica and western Panamá. These venom proteomes share a conserved compositional pattern reported in four other congeneric species within the clade of South American Porthidium species, P. nasutum, P. lansbergii, P. ophryomegas, and P. porrasi. The paraspecific immunorecognition profile of antivenoms produced in Costa Rica (ICP polyvalent), Perú (Instituto Nacional de Salud) and Brazil (soro antibotrópico pentavalente, SAB, from Instituto Butantan) against the venom of P. arcosae was investigated through a third-generation antivenomics approach. The maximal venom-binding capacities of the investigated antivenoms were 97.1 mg, 21.8 mg, and 25.7 mg of P. arcosae venom proteins per gram of SAB, ICP, and INS-PERU antibody molecules, respectively, which translate into 28.4 mg, 13.1 mg, and 15.2 mg of total venom proteins bound per vial of SAB, ICP, and INS-PERU AV. The antivenomics results suggest that 21.8%, 7.8% and 6.1% of the SAB, ICP, and INS-PERU antibody molecules recognized P. arcosae venom toxins. The SAB antivenom neutralized P. arcosae venom's lethality in mice with an ED50 of 31.3 mgV/g SAB AV. This preclinical neutralization paraspecificity points to Brazilian SAB as a promising candidate for the treatment of envenomings by Ecuadorian P. arcosae. BIOLOGICAL SIGNIFICANCE: Assessing the preclinical efficacy profile of antivenoms against homologous and heterologous medically relevant snake venoms represents an important goal towards defining the biogeographic range of their clinical utility. This is particularly relevant in regions, such as Mesoamerica, where a small number of pharmaceutical companies produce antivenoms against the venoms of a small number of species of maximum medical relevance among the local rich herpetofauna, leaving a wide range of snakes of secondary medical relevance, but also causing life-threatening human envenomings without nominal clinical coverage. This work is part of a larger project aiming at mapping the immunological characteristics of antivenoms generated in Latin American countries towards venoms of such poorly studied snakes of the local and neighboring countries' herpetofauna. Here we report the proteomics characterization of the Manabi hognosed pitviper Porthidium arcosae endemic to the western coastal province of Manabí (Ecuador), and the Costa Rican hognosed pitviper P. volcanicum with distribution restricted to southwestern Costa Rica, the antivenomics assessment of three bothropoid commercial antivenoms produced in Costa Rica, Perú, and Brazil against the venom components of P. arcosae, and the in vivo capacity of the Brazilian soro antibotrópico pentavalente (SAB) from Instituto Butantan to neutralize the murine lethality of P. arcosae venom. The preclinical paraspecific ED50 of 31.3 mg of P. arcosae venom per gram of antivenom points to Brazilian SAB as a promising candidate for the treatment of envenomings by the Manabi hognosed pitviper P. arcosae.


Asunto(s)
Venenos de Crotálidos , Crotalinae , Animales , Antivenenos , Ratones , Proteoma , Proteómica , Venenos de Serpiente
6.
Chem Biol Interact ; 346: 109581, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34302801

RESUMEN

Bothrops asper is one of the most important snake species in Central America, mainly because of its medical importance in countries like Ecuador, Panama and Costa Rica, where this species causes a high number of snakebite accidents. Several basic phospholipases A2 (PLA2s) have been previously characterized from B. asper venom, but few studies have been carried out with its acidic isoforms. In addition, since snake venom is a rich source of bioactive substances, it is necessary to investigate the biotechnological potential of its components. In this context, this study aimed to carry out the biochemical characterization of PLA2 isoforms isolated from B. asper venom and to evaluate the antiparasitic potential of these toxins. The venom and key fractions were subjected to different chromatographic steps, obtaining nine PLA2s, four acidic ones (BaspAc-I, BaspAc-II, BaspAc-III and BaspAc-IV) and five basic ones (BaspB-I, BaspB-II, BaspB-III, BaspB-IV and BaspB-V). The isoelectric points of the acidic PLA2s were also determined, which presented values ranging between 4.5 and 5. The findings indicated the isolation of five unpublished isoforms, four Asp49-PLA, corresponding to the group of acidic isoforms, and one Lys49-PLA2-like. Acidic PLA2s catalyzed the degradation of all substrates evaluated; however, for the basic PLA2s, there was a preference for phosphatidylglycerol and phosphatidic acid. The antiparasitic potential of the toxins was evaluated, and the acidic PLA2s demonstrated action against the epimastigote forms of T. cruzi and promastigote forms of L. infantum, while the basic PLA2s BaspB-II and BaspB-IV showed activity against P. falciparum. The results indicated an increase of up to 10 times in antiplasmodial activity, when the Asp49-PLA2 and Lys49-PLA2 were associated with one another, denoting synergistic action between these PLA2 isoforms. These findings correspond to the first report of synergistic antiplasmodial action for svPLA2s, demonstrating that these molecules may be important targets in the search for new antiparasitic agents.


Asunto(s)
Antiprotozoarios/farmacología , Fosfolipasas A2/química , Plasmodium falciparum/efectos de los fármacos , Venenos de Serpiente/metabolismo , Secuencia de Aminoácidos , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Bothrops/metabolismo , Sinergismo Farmacológico , Punto Isoeléctrico , Leishmania infantum/efectos de los fármacos , Panamá , Pruebas de Sensibilidad Parasitaria , Fosfolipasas A2/aislamiento & purificación , Fosfolipasas A2/farmacología , Isoformas de Proteínas/química , Isoformas de Proteínas/aislamiento & purificación , Isoformas de Proteínas/farmacología , Alineación de Secuencia
7.
Int J Biol Macromol ; 175: 572-585, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33529631

RESUMEN

A basic sPLA2 (D49) from the venom of snake Agkistrodon piscivorus leucostoma (AplTX-II) was isolated, purified and characterized. We determined the enzymatic and pharmacological profiles of this toxin. AplTX-II was isolated with a high level of purity through reverse phase chromatography and molecular exclusion. The enzyme showed pI 9.48 and molecular weight of 14,003 Da. The enzymatic activity of the AplTX-II depended on Ca2+ pH and temperature. The comparison of the primary structure with other sPLA2s revealed that AplTX-II presented all the structural reasons expected for a basic sPLA2s. Additionally, we have resolved its structure with the docked synthetic substrate NOBA (4-nitro-3-octanoyloxy benzoic acid) by homology modeling, and performed MD simulations with explicit solvent. Structural similarities were found between the enzyme's modeled structure and other snake sPLA2 X-Ray structures, available in the PDB database. NOBA and active-site water molecules spontaneously adopted stable positions and established interactions in full agreement with the reaction mechanism, proposed for the physiological substrate, suggesting that NOBA hydrolysis is an excellent model to study phospholipid hydrolysis.


Asunto(s)
Agkistrodon/metabolismo , Fosfolipasas A2 Secretoras/aislamiento & purificación , Venenos de Serpiente/química , Agkistrodon/fisiología , Secuencia de Aminoácidos , Animales , Venenos de Crotálidos/enzimología , Peso Molecular , Fosfolipasas A2 Secretoras/química , Fosfolipasas A2 Secretoras/metabolismo , Fosfolípidos/química , Venenos de Serpiente/aislamiento & purificación , Serpientes
8.
Toxicon ; 193: 63-72, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33503404

RESUMEN

Bothrops atrox is the most clinically relevant snake species within the Amazon region, which includes Ecuadorian territories. It comprises a large distribution, which could contribute to the genetic and venomic variation identified in the species. The high variability and protein isoform diversity of its venom are of medical interest, since it can influence the clinical manifestations caused by envenomation and its treatment. However, in Ecuador there is insufficient information on the diversity of venomic phenotypes, even of relevant species such as B. atrox. Here, we characterized the biochemical and toxicological profiles of the venom of six B. atrox individuals from the Ecuadorian Amazon. Differences in catalytic activities of toxins, elution profiles in liquid chromatography, electrophoretic patterns, and toxic effects among the analyzed samples were identified. Nonetheless, in the preclinical testing of antivenom, two samples from Mera (Pastaza) required a higher dose to achieve total neutralization of lethality and hemorrhage. Taken together, these data highlight the importance of analyzing individual venoms in studies focused on the outcomes of envenoming.


Asunto(s)
Bothrops , Venenos de Crotálidos , Animales , Antivenenos/uso terapéutico , Venenos de Crotálidos/toxicidad , Ecuador , Serpientes
9.
Curr Issues Mol Biol ; 44(1): 46-62, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-35723383

RESUMEN

The membrane-active nature of phospholipase A2-derived peptides makes them potential candidates for antineoplastic and antibacterial therapies. Two short 13-mer C-terminal fragments taken from snake venom Lys49-PLA2 toxins (p-AppK and p-Acl), differing by a leucine/phenylalanine substitution, were synthesized and their bioactivity was evaluated. Their capacity to interfere with the survival of Gram-positive and Gram-negative bacteria as well as with solid and liquid tumors was assessed in vitro. Toxicity to red blood cells was investigated via in silico and in vitro techniques. The mode of action was mainly studied by molecular dynamics simulations and membrane permeabilization assays. Briefly, both peptides have dual activity, i.e., they act against both bacteria, including multidrug-resistant strains and tumor cells. All tested bacteria were susceptible to both peptides, Pseudomonas aeruginosa being the most affected. RAMOS, K562, NB4, and CEM cells were the main leukemic targets of the peptides. In general, p-Acl showed more significant activity, suggesting that phenylalanine confers advantages to the antibacterial and antitumor mechanism, particularly for osteosarcoma lines (HOS and MG63). Peptide-based treatment increased the uptake of a DNA-intercalating dye by bacteria, suggesting membrane damage. Indeed, p-AppK and p-Acl did not disrupt erythrocyte membranes, in agreement with in silico predictions. The latter revealed that the peptides deform the membrane and increase its permeability by facilitating solvent penetration. This phenomenon is expected to catalyze the permeation of solutes that otherwise could not cross the hydrophobic membrane core. In conclusion, the present study highlights the role of a single amino acid substitution present in natural sequences towards the development of dual-action agents. In other words, dissecting and fine-tuning biomembrane remodeling proteins, such as snake venom phospholipase A2 isoforms, is again demonstrated as a valuable source of therapeutic peptides.

10.
Toxicon X ; 7: 100051, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32760910

RESUMEN

Snakebite envenoming is a neglected disease of public health concern. Most snakebite accidents occur in developing countries. In Ecuador, 17 viper species are responsible for 99% of official accidents, and ten species are in critical conservation states. This report analyzes the snakebite incident cases and mortality rates in Ecuador between 2014 and 2019. The data obtained from the national surveillance system suggests that the incidence and mortality rates remained constant. The geographic region with the highest incidence rates is the Amazonian region. National policies are urgently needed to prevent snakebite accidents and to protect snakes in danger of extinction.

11.
Artículo en Inglés | MEDLINE | ID: mdl-31911190

RESUMEN

Bothrops asper and Bothrops atrox are important venomous snakes from Ecuador responsible for the most of ophidic accidents, which in the past were treated with a national polyvant antivenom. For years, the venom pools were collected and stored at room temperature in a laboratory. Taking into account the controversial ability of desiccated samples to retain their biological effects and enzymatic activities, we investigated the biochemical and toxicological properties of venoms after years of storage. The proteomic profiles of historical venoms analyzed by high-performance liquid chromatography and electrophoresis are very similar. The fresh batches of venom were more lethal than those stored for years, just as the initial and current LD50 values of these samples changed. Significant differences were showed in the myotoxic and hemorrhagic activity of some venom pools, while no significant statistical differences were found for the edema activity. The enzymatic assays revealed a variation in proteolytic activity on azocasein and phospholipase A2 activity, and low differences were reported for thrombin-like serine protease activity. The maintenance of the proteomic profile and certain toxicological activities convert this venom library in a valuable source for research purposes. Nonetheless, the significative reduction of toxicological activities, such as hemorrhagic activity not feasible using these samples for the antivenom production.


Asunto(s)
Venenos de Crotálidos/química , Animales , Bothrops/metabolismo , Desecación , Ecuador , Estabilidad de Enzimas , Dosificación Letal Mediana , Masculino , Ratones , Proteómica , Manejo de Especímenes
12.
Artículo en Inglés | MEDLINE | ID: mdl-31454702

RESUMEN

Phospholipase A2 toxins present in snake venoms interact with biological membranes and serve as structural models for the design of small peptides with anticancer, antibacterial and antiparasitic properties. Oligoarginine peptides are capable of increasing cell membrane permeability (cell penetrating peptides), and for this reason are interesting delivery systems for compounds of pharmacological interest. Inspired by these two families of bioactive molecules, we have synthesized two 13-mer peptides as potential antileishmanial leads gaining insights into structural features useful for the future design of more potent peptides. The peptides included p-Acl, reproducing a natural segment of a Lys49 PLA2 from Agkistrodon contortrix laticinctus snake venom, and its p-AclR7 analogue where all seven lysine residues were replaced by arginines. Both peptides were active against promastigote and amastigote forms of Leishmania (L.) amazonensis and L. (L.) infantum, while displaying low cytotoxicity for primary murine macrophages. Spectrofluorimetric studies suggest that permeabilization of the parasite's cell membrane is the probable mechanism of action of these biomolecules. Relevantly, the engineered peptide p-AclR7 was more active in both life stages of Leishmania and induced higher rates of ethidium bromide incorporation than its native template p-Acl. Taken together, the results suggest that short peptides based on phospholipase toxins are potential scaffolds for development of antileishmanial candidates. Moreover, specific amino acid substitutions, such those herein employed, may enhance the antiparasitic action of these cationic peptides, encouraging their future biomedical applications.


Asunto(s)
Venenos de Crotálidos/farmacología , Leishmania infantum/efectos de los fármacos , Leishmaniasis Visceral/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Péptidos/farmacología , Fosfolipasas A2/farmacología , Agkistrodon/metabolismo , Animales , Células Cultivadas , Venenos de Crotálidos/síntesis química , Macrófagos/citología , Ratones , Ratones Endogámicos BALB C , Péptidos/síntesis química
13.
Drug Dev Res ; 80(1): 68-85, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30255943

RESUMEN

The emergence of antibiotic resistance drives an essential race against time to reveal new molecular structures capable of addressing this alarming global health problem. Snake venoms are natural catalogs of multifunctional toxins and privileged frameworks, which serve as potential templates for the inspiration of novel treatment strategies for combating antibiotic resistant bacteria. Phospholipases A2 (PLA2 s) are one of the main classes of antibacterial biomolecules, with recognized therapeutic value, found in these valuable secretions. Recently, a number of biomimetic oligopeptides based on small fragments of primary structure from PLA2 toxins has emerged as a meaningful opportunity to overcome multidrug-resistant clinical isolates. Thus, this review will highlight the biochemical and structural properties of antibacterial PLA2 s and peptides thereof, as well as their possible molecular mechanisms of action and key roles in development of effective therapeutic strategies. Chemical strategies possibly useful to convert antibacterial peptides from PLA2 s to efficient drugs will be equally addressed.


Asunto(s)
Farmacorresistencia Microbiana/efectos de los fármacos , Fosfolipasas A2/aislamiento & purificación , Fosfolipasas A2/farmacología , Venenos de Serpiente/enzimología , Venenos de Serpiente/farmacología , Animales , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/farmacología , Farmacorresistencia Microbiana/fisiología , Humanos
14.
Curr Pharm Biotechnol ; 19(4): 308-335, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29929461

RESUMEN

BACKGROUND: Research involving snake venom has gradually surpassed the simple discovery of new molecules using purification and structural characterization processes, and extended to the identification of their molecular targets and the evaluation of their therapeutic potential. Nevertheless, this only became possible due to constant progress in experimental biology and protein purification approaches. OBJECTIVE: This review aims to discuss the main components of snake venoms that have been investigated for biotechnological purposes, and to discover how these promising biomolecules were obtained with the satisfactory degree of purity that have enabled such studies. Advances in purification technologies of various snake venom molecules have allowed for important discoveries of proteins and peptides with different biomedical and biotechnological applications. RESULT AND CONCLUSION: It is believed that significant experimental and computational advances will arise in similar proportions in the coming years that will allow researchers to map the molecular regions responsible for their pharmacological actions, their respective mechanisms of action and their cell targets.


Asunto(s)
Venenos de Serpiente/química , Venenos de Serpiente/farmacología , Serpientes/fisiología , Animales , Descubrimiento de Drogas , Humanos , Proteínas/química , Venenos de Serpiente/genética , Venenos de Serpiente/uso terapéutico
15.
Artículo en Inglés | MEDLINE | ID: mdl-29604435

RESUMEN

The neuromuscular effect of venoms is not a major clinical manifestation shared between rattlesnakes native to the Americas, which showed two different venom phenotypes. Taking into account this dichotomy, nerve muscle preparations from mice and chicks were used to investigate the ability of Crotalus atrox venom to induce in vitro neurotoxicity and myotoxicity. Unlike crotalic venoms of South America, low concentrations of C. atrox venom did not result in significant effects on mouse neuromuscular preparations. The venom was more active on avian nerve-muscle, showing reduction of twitch heights after 120 min of incubation with 10, 30 and 100 µg/mL of venom with diminished responses to agonists and KCl. Histological analysis highlighted that C. atrox was myotoxic in both species of experimental animals; as evidenced by degenerative events, including edematous cells, delta lesions, hypercontracted fibers and muscle necrosis, which can lead to neurotoxic action. These results provide key insights into the myotoxicity and low neurotoxicity of C. atrox in two animal models, corroborating with previous genomic and proteomic findings and would be useful for a deeper understanding of venom evolution in snakes belonging to the genus Crotalus.


Asunto(s)
Venenos de Crotálidos/farmacología , Crotalus/fisiología , Músculo Esquelético/efectos de los fármacos , Fibras Nerviosas/efectos de los fármacos , Bloqueantes Neuromusculares/farmacología , Unión Neuromuscular/efectos de los fármacos , Animales , Pollos , Crotalus/crecimiento & desarrollo , Diafragma/citología , Diafragma/efectos de los fármacos , Diafragma/inervación , Diafragma/fisiología , Resistencia a Medicamentos , Técnicas In Vitro , Masculino , Ratones , Contracción Muscular/efectos de los fármacos , Músculo Esquelético/citología , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Fibras Nerviosas/fisiología , Unión Neuromuscular/fisiología , América del Norte , Especificidad de Órganos , Músculos Paraespinales/citología , Músculos Paraespinales/efectos de los fármacos , Músculos Paraespinales/inervación , Músculos Paraespinales/fisiología , Nervio Frénico/citología , Nervio Frénico/efectos de los fármacos , Nervio Frénico/fisiología , Especificidad de la Especie , Nervios Espinales/citología , Nervios Espinales/efectos de los fármacos , Nervios Espinales/fisiología
16.
Eur J Med Chem ; 149: 248-256, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29501945

RESUMEN

Currently, the evolving and complex mechanisms of bacterial resistance to conventional antibiotics are increasing, while alternative medicines are drying up, which urges the need to discover novel agents able to kill antibiotic-resistant bacteria. Lys49 phospholipase A2s (PLA2s) from snake venoms are multifunctional toxins able to induce a huge variety of therapeutic effects and consequently serve as templates for new drug leads. Hence, the present study was aimed at the synthesis of oligopeptides mimicking regions of the antibacterial Lys49 PLA2 toxin (CoaTx-II), recently isolated from Crotalus oreganus abyssus snake venom, to identify small peptides able to reproduce the therapeutic action of the toxin. Five peptides, representing major regions of interest within CoaTx-II, were synthesized and screened for their antibacterial properties. The 13-mer peptide pC-CoaTxII, corresponding to residues 115-129 of CoaTx-II, was able to reproduce the promising bactericidal effect of the toxin against multi-resistant clinical isolates. Peptide pC-CoaTxII is mainly composed by positively charged and hydrophobic amino acids, a typical trait in most antimicrobial peptides, and presented no defined secondary structure in aqueous environment. The physicochemical properties of pC-CoaTxII are favorable towards a strong interaction with anionic lipid membranes as those in bacteria. Additional in silico studies suggest formation of a water channel across the membrane upon peptide insertion, eventually leading to bacterial cell disruption and death. Overall, our findings confirm the valuable potential of snake venom toxins towards design and synthesis of novel antimicrobials, thus representing key insights towards development of alternative efficient antimicrobials to fight bacterial resistance to current antibiotics.


Asunto(s)
Antibacterianos/síntesis química , Oligopéptidos/síntesis química , Fosfolipasas A2/química , Venenos de Serpiente/enzimología , Animales , Permeabilidad de la Membrana Celular , Crotalus , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Oligopéptidos/química , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/química , Peptidomiméticos/síntesis química , Solubilidad
17.
Int J Biol Macromol ; 107(Pt A): 1014-1022, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28951306

RESUMEN

Phospholipases A2 (PLA2s) are important enzymes present in snake venoms and are related to a wide spectrum of pharmacological effects, however the toxic potential and therapeutic effects of acidic isoforms have not been fully explored and understood. Due to this, the present study describes the isolation and biochemical characterization of two new acidic Asp49-PLA2s from Bothrops brazili snake venom, named Braziliase-I and Braziliase-II. The venom was fractionated in three chromatographic steps: ion exchange, hydrophobic interaction and reversed phase. The isoelectric point (pI) of the isolated PLA2s was determined by two-dimensional electrophoresis, and 5.2 and 5.3 pIs for Braziliase-I and II were observed, respectively. The molecular mass was determined with values ​​of 13,894 and 13,869Da for Braziliase-I and II, respectively. Amino acid sequence by Edman degradation and mass spectrometry completed 87% and 74% of the sequences, respectively for Braziliase-I and II. Molecular modeling of isolated PLA2s using acid PLA2BthA-I-PLA2 from B. jararacussu template showed high quality. Both acidic PLA2s showed no significant myotoxic activity, however they induced significant oedematogenic activity. Braziliase-I and II (100µg/mL) showed 31.5% and 33.2% of cytotoxicity on Trypanosoma cruzi and 26.2% and 19.2% on Leishmania infantum, respectively. Braziliase-I and II (10µg) inhibited 96.98% and 87.98% of platelet aggregation induced by ADP and 66.94% and 49% induced by collagen, respectively. The acidic PLA2s biochemical and structural characterization can lead to a better understanding of its pharmacological effects and functional roles in snakebites pathophysiology, as well as its possible biotechnological applications as research probes and drug leads.


Asunto(s)
Fosfolipasas A2/química , Inhibidores de Agregación Plaquetaria/química , Agregación Plaquetaria/efectos de los fármacos , Venenos de Serpiente/química , Secuencia de Aminoácidos/genética , Animales , Bothrops/genética , Leishmania infantum/efectos de los fármacos , Leishmania infantum/patogenicidad , Modelos Moleculares , Fosfolipasas A2/genética , Fosfolipasas A2/aislamiento & purificación , Fosfolipasas A2/farmacología , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Inhibidores de Agregación Plaquetaria/farmacología , Homología de Secuencia de Aminoácido , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/patogenicidad
18.
Toxicon ; 115: 13-21, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26927324

RESUMEN

Snake venom is a complex mixture of active compounds consisting of 80-90% proteins and peptides that exhibit a variety of biological actions that are not completely clarified or identified. Of these, phospholipase A2 is one of the molecules that has shown great biotechnological potential. The objectives of this study were to isolate, biochemically and biologically characterize a Lys49 phospholipase A2 homologue from the venom of Bothrops neuwiedi urutu. The protein was purified after two chromatographic steps, anion exchange and reverse phase. The purity and relative molecular mass were assessed by SDS-PAGE, observing a molecular weight typical of PLA2s, subsequently confirmed by mass spectrometry obtaining a mass of 13,733 Da. As for phospholipase activity, the PLA2 proved to be enzymatically inactive. The analyses by Edman degradation and sequencing of the peptide fragments allowed for the identification of 108 amino acid residues; this sequence showed high identity with other phospholipases A2 from Bothrops snake venoms, and identified this molecule as a novel PLA2 isoform from B. neuwiedi urutu venom, called BnuTX-I. In murine models, both BnuTX-I as well as the venom induced edema and myotoxic responses. The cytotoxic effect of BnuTX-I in murine macrophages was observed at concentrations above 12 µg/mL. BnuTX-I also presented antimicrobial activity against gram-positive and negative bacterial strains, having the greatest inhibitory effect on Pseudomonas aeruginosa. The results allowed for the identification of a new myotoxin isoform with PLA2 structure with promising biotechnological applications.


Asunto(s)
Antibacterianos/farmacología , Bothrops/metabolismo , Venenos de Crotálidos/química , Fosfolipasas A2/farmacología , Secuencia de Aminoácidos , Animales , Antibacterianos/química , Supervivencia Celular/efectos de los fármacos , Venenos de Crotálidos/aislamiento & purificación , Venenos de Crotálidos/farmacología , Edema/sangre , Edema/inducido químicamente , Edema/patología , Electroforesis en Gel de Poliacrilamida , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Interleucina-1beta/sangre , Masculino , Ratones , Fosfolipasas A2/química , Conformación Proteica , Pseudomonas aeruginosa/efectos de los fármacos , Alineación de Secuencia , Factor de Necrosis Tumoral alfa/sangre
19.
Artículo en Inglés | MEDLINE | ID: mdl-26827743

RESUMEN

Snake venom toxins are related not only in detention, death and the promotion of initial digestion of prey but also due to their different biochemical, structural and pharmacological effects they can result in new drugs. Among these toxins snake venom serine proteases (SVSPs) should be highlighted because they are responsible for inducing changes in physiological functions such as blood coagulation, fibrinolysis, and platelet aggregation. This article presents the first serine protease (SP) isolated from Bothrops brazili: BbrzSP-32. The new SP showed 36 kDa of relative molecular mass and its absolute mass was confirmed by mass spectrometry as 32,520 Da. It presents 79.48% identity when compared to other SVSPs and was able to degrade the α-chain of fibrinogen, in in vitro models, because of this it is considered a SVTLE-A. It showed dose-dependent activity in the process of degradation of fibrin networks demonstrating greater specificity for this activity when compared to its thrombolytic action. BbrzSP-32 demonstrated proteolytic activity on gelatin and chromogenic substrates for serine proteases and thrombin-like enzymes (S-2288 and S-2238 respectively), besides having coagulant activity on human plasma. After pre-incubation with PMSF and benzamidine the coagulant and proteolytic activities on the S-2288 and S-2238 substrates were reduced. BbrzSP-32 shows stability against pH and temperature variations, demonstrating optimum activity between 30 and 40 °C and in the pH range 7.5 to 8.5. A new SP with potential biotechnological application was isolated.


Asunto(s)
Venenos de Crotálidos/química , Serina Proteasas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Bothrops , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Serina Proteasas/química
20.
Toxicon ; 106: 30-41, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26363289

RESUMEN

This study describes the biochemical and functional characterization of a new metalloproteinase named BbMP-1, isolated from Bothrops brazili venom. BbMP-1 was homogeneous on SDS-PAGE, presented molecular mass of 22,933Da and pI 6.4. The primary structure was partially elucidated with high identity with others metalloproteinases from Viperidae venoms. The enzymatic activity on azocasein was evaluated in different experimental conditions (pH, temperature). A significant reduction in enzyme activity after exposure to chelators of divalent cations (EDTA), reducing agents (DTT), pH less than 5.0 or temperatures higher than 45 °C was observed. BbMP-1 showed activity on fibrinogen degrading Aα chain quickly and to a lesser extent the Bß chain. Also demostrated to be weakly hemorrhagic, presenting however, significant myotoxic and edematogenic activity. The in vitro activity of BbMP-1 against Plasmodium falciparum showed an IC50 of 3.2 ± 2.0 µg/mL. This study may help to understand the pathophysiological effects induced by this group of toxin and their participation in the symptoms observed in cases of snake envenomation. Moreover, this result is representative for this group of proteins and shows the biotechnological potential of BbMP-1 by the demonstration of its antiplasmodial activity.


Asunto(s)
Antiparasitarios/farmacología , Bothrops/metabolismo , Venenos de Crotálidos/enzimología , Metaloproteasas/química , Plasmodium falciparum/efectos de los fármacos , Animales , Antiparasitarios/química , Antiparasitarios/aislamiento & purificación , Caseínas/química , Caseínas/metabolismo , Electroforesis en Gel de Poliacrilamida , Fibrinógeno/química , Fibrinógeno/metabolismo , Concentración de Iones de Hidrógeno , Concentración 50 Inhibidora , Masculino , Metaloproteasas/aislamiento & purificación , Metaloproteasas/farmacología , Ratones , Modelos Moleculares , Simulación de Dinámica Molecular , Temperatura
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