Jellyfish are efficient predators which prey on crabs, fish larvae, and small fish. Their venoms consist of various toxins including neurotoxins that paralyse prey organisms immediately. One possible mode of action of neurotoxins is the blockage of voltage-gated sodium (Na v) channels. A novel polypeptide with Na v channel blocking activity was isolated from the northern Scyphozoa Cyanea capillata (L., 1758). For that purpose, a bioactivity-guided multidimensional liquid chromatographic purification method has been developed. A neurotoxic activity of resulting chromatographic fractions was demonstrated by a bioassay, which based on the mouse neuroblastoma cell line Neuro2A. The purification process yielded one fraction containing a single polypeptide with proven activity. The molecular weight of 8.22 kDa was determined by matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-ToF MS). Utilising Laser Microdissection and Pressure Catapulting (LMPC) for the separation of different nematocyst types in combination with direct MALDI-ToF MS analysis of the intact capsules, the neurotoxin was found to be present in all types of fishing tentacle isorhizas (A-isorhizas, a-isorhizas, O-isorhizas) of C. capillata medusae.
Jellyfish have an increasing impact on marine ecology. Cnidocysts bearing stinging cells afford, amongst others, prey capture and defence. Several different types of stinging capsules are found in one species and they are supposed to have specific functions, e.g. paralysing prey or adhering to it. Due to these assumed different roles of the capsules, it is suggested that toxins, which are contained in the capsules, differ in composition. Analysis of distinct types of nematocysts requires an appropriate method for the separation of the different types. Mixtures of types of nematocysts were obtained of two species of jellyfish, Aurelia aurita and Cyanea lamarckii, by maceration of the tissue. These mixtures were treated with a method called laser microdissection and pressure catapulting (LMPC). Optimized maceration methods, which were firstly introduced as a method for this purpose, in conjunction with optimized LMPC parameters lead to sufficient amounts of separated capsules of individual types for subsequent mass-spectrometric analyses. In case of A. aurita, the resulting mass spectra had some constituents in common, whereas in the overall pattern, the two distinct nematocyst types differed.
SUMMARY:The cnidocysts and the lytic, cyto-and neurotoxic potency of a large specimen of Cyanea capillata (L.) with 55 cm umbrella diameter were compared with those of a pooled C. capillata sample (average ø 14 cm) in order to investigate organismal developments at a cellular and biochemical level. Nematocysts of the type A-isorhiza in both fishing tentacles and oral arms and the O-isorhizas of oral arms were enlarged in the 55 cm specimen. Additionally, the number of nematocysts per battery in the fishing tentacles was increased. Increased gill cell toxicity and neurotoxic activity were demonstrated for the fishing tentacle venom of the 55 cm C. capillata in comparison with the smaller medusae. A two-fold higher haemolytic activity was detected for the venom of oral arms obtained from the large C. capillata compared with the oral arm venom prepared from the smaller medusae.Keywords: Cnidaria, Scyphozoa, Cyanea, jellyfish, cnidom, venom, cytotoxicity, neurotoxicity. RESUMEN: Análisis del cnidoma combinado con una evaluación in vitro del potencial lítico, cyto-y neurotóxicos de Cyanea Capillata (Cnidaria: Scyphozoa). -Con el fin de estudiar la evolución ontogenética a un nivel celular y bioquímico de los cnidocistos de la potencia lítica, y las características cito-y neurotóxicas de Cyanea capillata (L.), se ha comparado un ejemplar de 55 cm de diámetro de umbrela de la especie con una muestra de varios ejemplares de C. capillata (promedio 14 cm de diámetro). Tanto los nematocistos del tipo A isorhiza de los tentáculos marginales como en los mesentéricos y los nematocistos del tipo O isorhizas de tentáculos orales fueron mayores en el ejemplar de C. capillata de 55 cm. Además, el número de nematocistos por zona de agregación fue mayor en el ejemplar de 55 cm. En cuanto a la actividad tóxica de los cnidocistos, ésta fue superior tanto a nivel de célula como de la actividad de la toxina (veneno) en los tentáculos marginales del ejemplar de 55 cm frente a los ejemplares más pequeños de la especie. También se observó una actividad hemolítica de la toxina (veneno) dos veces superior en los cnidocistos de los tentáculos marginales del ejemplar grande, 55 cm de C. capillata frente a los ejemplares pequeños.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.