Sequence analysis of the cDNA encoding for SpCTx: a lethal factor from scorpionfish venom ( Scorpaena plumieri )

Lethal factors are multifunctional oligomeric proteins found in the venomous apparatus of Scorpaeniformes fish. These toxins elicit not only an array of biological responses in vitro but also cardiovascular disorders and strong hemolytic, nociceptive and edematogenic activities in vivo. This work describes the cloning and molecular identification of two toxin subunits, denominated Sp-CTx-α and Sp-CTx-ß, from scorpionfish venom ( Scorpaena plumieri ). Methods: The primary structures were deduced after cDNA amplification by PCR with primers from conserved sequences described in Scorpaeniformes toxins. Following DNA sequencing and bioinformatic analysis, the tridimensional structures of both subunits were modeled. Results: The translated sequences (702 amino acids, each subunit) show homology with other lethal factors, while alignment between Sp-CTx-α and Sp-CTx-ß shows 54% identity. The subunits lack N-terminal signal sequences and display masses of approximately 80 kDa each. Both Sp-CTx subunits display a B30.2/SPRY domain at the C-terminal region with typically conserved motifs as described in these toxins. Secondary structure prediction identified six α-helices 18 residues long in both α and ß subunits, some of them amphiphilic with their N-terminal flanked by many basic residues, creating a cationic site associated with the cytolytic activity of these toxins. Antimicrobial potential sites were identified in Sp-CTx and share some features with other peptides presenting variable and broad-spectrum activity. A phylogenetic tree built to represent these toxins supports the proximity between scorpionfish, lionfish and stonefish. Conclusion: The study identified a putative toxin protein whose primary structure is similar to other fish toxins and with potential for production of antivenom against scorpionfish envenomation in Brazil. As a prelude to structure-function studies, we propose that the toxin is structurally related to pore-forming marine toxins.(AU)

Sequence analysis of the cDNA encoding for SpCTx: a lethal factor from scorpionfish venom ( Scorpaena plumieri )

Background: Lethal factors are multifunctional oligomeric proteins found in the venomous apparatus of Scorpaeniformes fish. These toxins elicit not only an array of biological responses in vitro but also cardiovascular disorders and strong hemolytic, nociceptive and edematogenic activities in vivo. This work describes the cloning and molecular identification of two toxin subunits, denominated Sp-CTx- and Sp-CTx-, from scorpionfish venom ( Scorpaena plumieri ). Methods: The primary structures were deduced after cDNA amplification by PCR with primers from conserved sequences described in Scorpaeniformes toxins. Following DNA sequencing and bioinformatic analysis, the tridimensional structures of both subunits were modeled. Results: The translated sequences (702 amino acids, each subunit) show homology with other lethal factors, while alignment between Sp-CTx- and Sp-CTx- shows 54% identity. The subunits lack N-terminal signal sequences and display masses of approximately 80 kDa each. Both Sp-CTx subunits display a B30.2/SPRY domain at the C-terminal region with typically conserved motifs as described in these toxins. Secondary structure prediction identified six -helices 18 residues long in both and subunits, some of them amphiphilic with their N-terminal flanked by many basic residues, creating a cationic site associated with the cytolytic activity of these toxins. Antimicrobial potential sites were identified in Sp-CTx and share some features with other peptides presenting variable and broad-spectrum activity...

A review on the Scorpaena plumieri fish venom and its bioactive compounds

The most poisonous fish species found along the Brazilian coast is the spotted scorpionfish Scorpaena plumieri. Though hardly ever life-threatening to humans, envenomation by S. plumieri can be quite hazardous, provoking extreme pain and imposing significant socioeconomic costs, as the victims may require days to weeks to recover from their injuries. In this review we will walk the reader through the biological features that distinguish this species as well as the current epidemiological knowledge related to the envenomation and its consequences. But above all, we will discuss the challenges involved in the biochemical characterization of the S. plumieri venom and its compounds, focusing then on the successful isolation and pharmacological analysis of some of the bioactive molecules responsible for the effects observed upon envenomation as well as on experimental models. Despite the achievement of considerable progress, much remains to be done, particularly in relation to the non-proteinaceous components of the venom. Therefore, further studies are necessary in order to provide a more complete picture of the venom's chemical composition and physiological effects. Given that fish venoms remain considerably less studied when compared to terrestrial venoms, the exploration of their full potential opens a myriad of possibilities for the development of new drug leads and tools for elucidating the complex physiological processes.(AU)

A review on the Scorpaena plumieri fish venom and its bioactive compounds

The most poisonous fish species found along the Brazilian coast is the spotted scorpionfish Scorpaena plumieri. Though hardly ever life-threatening to humans, envenomation by S. plumieri can be quite hazardous, provoking extreme pain and imposing significant socioeconomic costs, as the victims may require days to weeks to recover from their injuries. In this review we will walk the reader through the biological features that distinguish this species as well as the current epidemiological knowledge related to the envenomation and its consequences. But above all, we will discuss the challenges involved in the biochemical characterization of the S. plumieri venom and its compounds, focusing then on the successful isolation and pharmacological analysis of some of the bioactive molecules responsible for the effects observed upon envenomation as well as on experimental models. Despite the achievement of considerable progress, much remains to be done, particularly in relation to the non-proteinaceous components of the venom. Therefore, further studies are necessary in order to provide a more complete picture of the venoms chemical composition and physiological effects. Given that fish venoms remain considerably less studied when compared to terrestrial venoms, the exploration of their full potential opens a myriad of possibilities for the development of new drug leads and tools for elucidating the complex physiological processes.

Envenenamiento por pez escorpión (Scorpaena plumieri) en comunidad pesquera y turística de la península de Paraguaná, estado Falcón Venezuela: aspecto clínicos, epidemiológicos y tratamiento / Scorpionfish (Scorpaena plumieri) envenomation in a fishing and turistic community pf Paraguaná peninsula Falcon state Venezuela: clinical, epidemiological and treatment aspects

Entre diciembre 2006 y abril de 2007, se realizó un estudio descriptivo y prospectivo para analizar los perfiles clínicos, epidemiológicos y del tratamiento de los envenenamientos ocasionados por el pez escorpión Scorpaena plumieri en 36 individuos que se presentaron en la emergencia ambulatoria de Adícora, estado Falcón, Venezuela. Los porcentajes de envenenamientos no fueron estadísticamente significativos entre sexos ni grupos etarios (X2=0,03, p= 0,758; X2=0,06; p= 0,81, respectivamente). Los accidentes predominaron durante los meses festivos de febrero y abril (> 50%), lo que sugiere un patrón estacional, en horas vespertinas (83,33%) y a orillas de la playa (97,22%). Los pacientes asistieron a la emergencia ambulatoria entre 3 a 30 min después del accidente, con un tiempo promedio de 5,97 ± 4,39. Las heridas se presentaron de forma cortante, localizadas en su totalidad en la región plantar del pie, con longitudes entre 0,2 a 3 cm ( =1,04 ± 0,86) y profundidad entre 1 y 2 mm. Las manifestaciones clínicas observadas fueron: dolor intenso e irradiado (100%) [escala visual analógica VAS= : 9,39 ± 0,60], edema (27,78%) y eritema (22,22%). Un individuo presentó complicaciones sistémicas: hipotensión y desmayo. El tratamiento consistió de lidocaína (1%) infiltrada, anti-inflamatorio-analgésico sistémico vía oral (100 mg, cada 8 horas por 5 días) y antibióticoterapia per os (500 mg/2 veces al día/ 10 días), con evolución postratamiento satisfactoria entre 5 a 120 min ( = 30,11 ± 33,30) VAS de dolor promedio significativamente menor (0,72 ± 0,62; t= 52,2, p= 0,0001).