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Rough-skinned newts, Taricha granulosa , which contain tetrodotoxin (TTX), a potent neurotoxin, are widely distributed along the west-coast of North America up to British Columbia (BC), Canada, and Southeast Alaska. Their genetic population structure using DNA-microsatellites and the TTX-content of specimens from British Columbia (Prince Rupert area) and Alaska (Revillagigedo Island, Shelter Island, and Juneau) were analysed. TTX-concentrations were low in newts from BC and Revillagigedo Island, but high in specimens from mainland Juneau, which had been deliberately introduced from Shelter Island, where TTX was not detectable in the individuals sampled. No significant genetic differences were detected between these populations, which may correlate with the high intraspecies variability of TTX. It is still an open question, which factors favour or induce the toxin production in the newts. • Southeast Alaska is the northern range limit of the rough-skinned newt, Taricha granulosa. • The newts contain highly variable concentrations of tetrodotoxin. • Genetic testing using DNA-microsatellites provided no correlation of toxin-levels and population structure. • Other, still unknown, endo- and/or exogenous factors may trigger the high variability of the toxin-levels in the newts. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) contents of wild-caught Chinese red-bellied newts, Cynops orientalis , and their offspring captive-reared from eggs to metamorphosed juveniles, were analysed using post-column LC-fluorescent detection (LC-FLD) and high resolution hydrophilic interaction liquid chromatography/mass spectrometry (HR-HILIC-LC/MS). TTX was detected in the parent newts and their eggs, but not in the larvae and juveniles raised under artificial condition over 20 months. However, juveniles reared in the presence of their parents, contained TTX-concentrations up to 8.05 μg/g. The origin of TTX may be implied from a close connection between the parents and their offspring. • Wild-caught newts, Cynops orientalis , contain high concentrations of tetrodotoxin (TTX). • Captive-reared offspring is entirely free of TTX. • But when raised in the presence of their parents, juveniles become toxic. [ABSTRACT FROM AUTHOR]

Based on its mandibular gland secretion, the earless monitor lizard, Lanthanotus borneensis, has been considered a venomous animal like other members of the Toxicofera group, including Heloderma. In the present study, the gland structure and teeth of L. borneensis were examined by micro-tomography (μCT) and scanning electron microscopy (SEM), respectively, and proteomic analysis of the gland extract was performed. The mandibular gland consists of six compartments with separate ducts. The pleurodont teeth of the lower and upper jaw are not grooved but possess a sharp ridge on the anterior surface. Proteomic analysis of the gland extract confirmed previous studies that kallikrein enzymes are the major biologically active components. In view of the lizard's biology, its mandibular gland secretion is obviously not needed for prey capture or defence. It seems not justified the labelling of L. borneensis as a venomous animal. However, definitively answering this question requires toxinological studies on natural prey. Image 1 • The structure of the mandibular gland of the earless monitor lizard Lanthanotus borneensis was examined by micro-tomography. • The structure of the pleurodont teeth of L. borneensis was examined by scanning electron microscopy. • Proteomic analysis of the mandibular gland extract of the earless monitor confirmed kallikrein as a major components. • Collectively, the data from this study does not justify labelling L. borneensis as a "venomous" anguimorph lizard. [ABSTRACT FROM AUTHOR]

Red-spotted newts, Notophthalmus viridescens , contain tetrodotoxin (TTX) and its analogue 6- epi TTX in variable concentrations. In a follow-up study, newts were sampled from a pond in Pennsylvania, USA, in 2010, 2014, and 2018. Their toxin levels were assayed by liquid-chromatography-fluorescence detection (LC-FLD), and assessment of their infection with endoparasites such as nematodes and helminths was performed by histological examination of internal organs. In the 2010 and 2014 samples, average prevalence of parasite infection was 53 and 60%, respectively, but reached 100% in the 2018 sample, where metacercaria stages of the digenean trematode genus Australapatemon / Apatemon (family: Strigeidae) were predominant causing severe tissue damage in liver and kidney. Mean values of TTX and 6- epi TTX were not significantly different in parasitized or parasite-free newts over the study period, confirming previous findings that host toxicity and parasite load are not negatively correlated. Whereas the role of TTX in defence against predators is undisputed, its efficacy to prevent parasitic infections is less obvious. Toxin-resistance of various metazoan parasites may promote their widespread occurrence in poisonous newts. • Poisonous red spotted newts have been shown to be infected with parasites. • In that follow-up study covering 8 years, newts were collected from the same pond. • Their tetrodotoxin content and parasite load was analysed. • Toxicity of the newts does not correlate with the rate of parasitic infections. [ABSTRACT FROM AUTHOR]

Abstract Because of its bitter taste, quinine elicits strong antifeedant and toxic effects in animals including arthropods. In the present study, two mantis, Sphodromantis viridis, Hierodula membranacea , and two spider species, Nephila edulis, Selenocosmia javanensis , were offered a quinine solution or prey (crickets) contaminated or injected with quinine, which they ingested and survived without apparent toxic symptoms. Analysis of their faeces and, in the case of spiders, of silk from their web revealed that quinine was excreted over a period of 8–12 (mantids) or 7 days (spiders). Interestingly, the silk glands of the spiders served as an additional excretory organ of quinine. Both, mantids and spiders were shown to tolerate high amounts of quinine in their prey. Obviously, the bitter taste of this compound is not perceived by their gustatory receptors and consequently triggers no aversive reactions. Highlights • Taste perception of harmful compounds is essential for survival. • The bitter taste of quinine usually elicits aversive reactions. • Mantids and spiders were shown to cope with high amounts of quinine. • Quinine is excreted in faeces and web silk. • Bitter taste perception seems to be highly variable in arthropods. [ABSTRACT FROM AUTHOR]

For the first time, alcohol extracts of Atelopus hoogmoedi from the Guiana Shield in Suriname and Guyana were analyzed for the presence of tetrodotoxin (TTX) and of its analogues by high resolution hydrophilic interaction liquid chromatography/mass spectrometry. One specimen from Suriname was found to contain TTX and 4- epi TTX. Using a monoclonal antibody-based immunohistochemical staining technique, TTX was localized mainly in the granular glands and epithelium of the skin, but not in internal organs except liver showing weak TTX-positive reaction. In two specimens collected in Guyana, none of the toxins were detected. [ABSTRACT FROM AUTHOR]

Salamanders have evolved a wide variety of antipredator mechanisms and behavior patterns, including toxins and noxious or adhesive skin secretions. The high bonding strength of the natural bioadhesives makes these substances interesting for biomimetic research and applications in industrial and medical sectors. Secretions of toxic species may help to understand the direct effect of harmful substances on the cellular level. In the present study, the biocompatibility of adhesive secretions from four salamander species ( Plethodon shermani , Plethodon glutinosus , Ambystoma maculatum , Ambystoma opacum ) were analyzed using the MTT assay in cell culture and evaluated against toxic secretions of Pleurodeles waltl , Triturus carnifex , Pseudotriton ruber , Tylototriton verrucosus , and Salamandra salamandra . Their effect on cells was tested in direct contact (direct culture) or under the influence of the extract (indirect exposure) in accordance with the protocol of the international standard norm ISO 10993-5. Human dermal fibroblasts (NHDF), umbilical vein endothelial cells (HUVEC), and articular chondrocytes (HAC), as well as the cell lines C2C12 and L929 were used in both culture types. While the adhesive secretions from Plethodon shermani are cytocompatible and those of Ambystoma opacum are even advantageous, those of Plethodon glutinosus and Ambystoma maculatum appear to be cytotoxic to NDHF and HUVEC. Toxic secretions from Salamandra salamandra exhibited harmful effects on all cell types. Pseudotriton ruber and Triturus carnifex secretions affected certain cell types marginally; those from Pleurodeles waltl and Tylototriton verrucosus were generally well tolerated. The study shows for the first time the effect of salamander secretions on the viability of different cell types in culture. Two adhesive secretions appeared to be cell compatible and are therefore promising candidates for future investigations in the field of medical bioadhesives. Among the toxic secretions tested, only two of the five had a harmful effect on cells, indicating different cell toxicity mechanisms. [ABSTRACT FROM AUTHOR]

Butterflies of the genus Danaus are known to sequester toxic cardenolides from milkweed host plants (Apocynaceae). In particular, Danaus plexippus efficiently sequesters and stores these compounds, whereas D. chrysippus , is considered to poorly sequester cardenolides. To estimate its sequestration capability compared with that of D. plexippus , larvae of both species were jointly reared on Asclepias curassavica and the major cardenolides of the host plant, calotropin and calactin, were analyzed in adults sampled at different time intervals after eclosion. Both cardenolides were detected in body and wings of D. plexippus . Whereas the calotropin-concentration remained constant over a period of 24 days, that of calactin steadily decreased. In the body, but not in the wings of D. chrysippus , calactin only was detected in low amounts, which was then almost completely lost during the following 8 days after eclosion, suggesting that in contrast to D. plexippus , cardenolides seem to be less important for that butterfly's defence against predators. [ABSTRACT FROM AUTHOR]

Caterpillars of the monarch butterfly, Danaus plexippus , feed on milkweed plants, Asclepias spp. (Apocynaceae), and sequester their toxic cardenolides aimed at deterring predators. Nevertheless, Chinese praying mantids, Tenodera sinensis , consume these caterpillars after removing the midgut (“gutting”) including its plant content. In the present study, monarch caterpillars raised on A. curassavica , and those of the death's-head hawkmoth, Acherontia atropos , raised on Atropa belladonna containing atropine, were fed to mantids, Hierodula membranacea , which removed the gut of both species discarding about 59% of cardenolides and more than 90% of atropine, respectively. The ingestion of these compounds produced no apparent ill effects in the mantids and both were excreted with faeces. On the other hand, when mantids were fed with larvae of two moth species, Amata mogadorensis and Brahmaea certia , raised on non-poisonous host plants, the mantids showed the same gutting behaviour, thereby discarding indigestible plant material. As polar compounds, e.g. cardenolides and atropine, are not absorbed from the mantids midgut and do not pass the gut membrane, this enables the mantids to feed on toxic prey. [ABSTRACT FROM AUTHOR]

Abstract Frogs of the family Dendrobatidae are known to contain toxic alkaloids in their skin secretion, but Allobates species of the closely related Aromobatidae family are considered to lack toxic secretions. However, contradictory results have been reported. Analyses of alcohol extracts from three different Allobates species from South-America (Guiana Shield), Central America (Costa Rica), and from the dendrobatid frog Silverstoneia flotator confirm the absence of alkaloids and tetrodotoxin in aromobatids and in a dendrobatid of the subfamily Colostethinae. Highlights • Neotropical frogs of the genus Allobates and Silverstoneia are closely related to the poison frog family Dendrobatidae. • Their skin secretions are also considered to be toxic. • Analysis of their skin extracts provided no evidence for the presence of toxic alkaloids or tetrodotoxin. [ABSTRACT FROM AUTHOR]

Toads of the genus Melanophryniscus contain toxic alkaloids sequestered from a diet of mainly ants and mites. Wild-caught specimens of M. klappenbachi were fed an alkaloid-free diet and their alkaloid profile was analyzed during 38 months in captivity. Individual alkaloid patterns varied considerably. Over time, the concentration of two alkaloids, pumiliotoxin 251D and 3,5-disubstituted indolizidine 195B , significantly declined, suggesting that the toads depend on continuous access to alkaloid-containing prey to maintain natural levels of their chemical defense. [ABSTRACT FROM AUTHOR]

Abstract: Frogs of the genus Phyllobates from Colombia are known to contain the highly toxic alkaloid batrachotoxin, but species from Central America exhibit only very low levels or are entirely free of this toxin. In the present study alcohol extracts from 101 specimens of Phyllobates lugubris and Phyllobates vittatus and 21 of three sympatric species (Dendrobates pumilio, Dendrobates auratus, Dendrobates granuliferus) from Costa Rica were analyzed by gas chromatography-mass spectrometry. Whereas the extracts of the Dendrobates species exhibited typical profiles of toxic alkaloids, those of the two Phyllobates species contained low levels of few alkaloids only, batrachotoxin was not detected. Although the feeding pattern of the Dendrobates and Phyllobates species are similar as revealed by examination of their stomach content (mainly ants and mites), the Phyllobates species are poorly sequestering alkaloids from their food source in contrast to the Dendrobates frogs. [Copyright &y& Elsevier]

Abstract: The International Society on Toxinology (IST) was founded in 1962 with its main purpose to advance knowledge on venoms, poisons and toxins of animal, plant and microbial origin. World Congresses of the Society and Symposia of the IST-Sections (European, Pan-American, Asia-Pacific) are regularly organized to promote communication and exchange of results in toxinology research. The officers of the Society, the President and Secretary-Treasurer, are assisted by a Council and they all are elected by the membership. IST sponsors the Redi Award to recognize distinguished work in the field of toxinology. Toxicon is the official journal of the Society. [Copyright &y& Elsevier]

Abstract: Tetrodotoxin (TTX) and its analogue 6-epiTTX had been detected in the red-spotted newt, Notophthalmus viridescens. Thirty specimens of a population from Pennsylvania, USA were histologically examined for the presence of intestinal parasites. More than 50% were found to be infected with nematodes (Trichocephalidae), trematodes or cestodes (Pseudophyllidae). The mean values of TTX and 6-epiTTX in parasitized and in non-parasitized newts were not significantly different. Using a monoclonal antibody-based immunoenzymatic technique, TTX was localized in the intestinal tissue as well as in the parasites indicating that they accumulate the toxin and suggesting that TTX and 6-epiTTX are not providing protection from parasites to the newts. [Copyright &y& Elsevier]

Abstract: High levels of tetrodotoxin (TTX) and of its analogue 6-epi-tetrodotoxin have been detected in skin and liver extracts of the red-spotted newt Notophthalmus viridescens assayed by a post-column fluorescent-HPLC system. Using a monoclonal antibody-based immunoenzymatic technique, TTX was localized in the granular glands of the epidermis as well as in the muscle layer between the muscle fibres, but also in most organs suggesting that TTX is stored in the whole body of the newt and is secreted by skin glands. [Copyright &y& Elsevier]

Abstract: Fish species of the genera Amphiprion and Premnas (Perciformes: Pomacentridae) as well as various crustaceans seek protection from predators among the tentacles of sea anemones, where they live essentially unharmed from stinging by the host''s nematocysts. The mucous coats of anemonefish and crustaceans have been suggested as mechanisms that prevent the discharge of the nematocysts upon contact. Whereas some fish species seem to produce their own protecting mucous coating, others may acquire mucus from the sea anemone during an acclimation period, as crustaceans do. Whether the natural or acquired mucus layers contain components that inhibit nematocyst discharge or simply lack compounds stimulating the stinging cell''s exocytosis is still unknown. [Copyright &y& Elsevier]

Abstract: Tetrodotoxin (TTX) and its analogue 6-epitetrodotoxin (6-epiTTX) were quantitatively assayed in 59 newts representing four Triturus species (Triturus alpestris, Triturus cristatus, Triturus helveticus, Triturus vulgaris) from southern Germany by a post-column fluorescent-HPLC system. Both toxins were detected in only 15 specimens of the four species. The toxins levels varied considerably among individuals (TTX: 0.11–9.0μg/g; 6-epiTTX: 0.05–17.0μg/g). 6-epiTTX was found to be the major component. [Copyright &y& Elsevier]

Abstract: In whole animal ethanolic extracts from adult specimens of Melanophryniscus atroluteus (27 specimens) and M. devincenzii (16 specimens) as well as of two egg clutches and four tadpole samples from the latter species, the major alkaloid pumiliotoxin (PTX) 251D and hydroquinone were assayed quantitatively by gas chromatography/mass spectrometry. All toad extracts contained high concentrations of PTX 251D and hydroquinone and exhibited considerable variation in the content of these compounds among individual specimens. The extracts of the eggs and tadpoles were entirely free of alkaloids as well as hydroquinone, pointing to a dietary origin of these compounds. [Copyright &y& Elsevier]

Abstract: The South-American red bellied toads (Melanophryniscus spp.) belonging to the Bufonidae family contain toxic alkaloids in their skin, predominantly of the pumiliotoxin group. Whole animal methanolic extracts of individual specimens of three species (Melanophryniscus atroluteus, M. devincenzii, and M. montevidensis) were analyzed for the presence of toad specific bufadienolides and indolalkylamines (serotonin derivatives) by HPLC-electrospray (ESI)-MS-TOF. No bufadienolides, but few bufotenines, mainly dehydrobufotenine, were detected in the extracts in variable amounts. The concentration of the dehydrobufotenine in the extracts seems to be species specific. Whereas M. atroluteus and M. montevidensis contain very low or trace amounts, M. devincenzii specimens exhibit high concentrations of this indolalkylamine. In comparison, analysis of extracts from Bufo arenarum (Uruguay) and from B. bufo (Germany) confirmed the presence of bufadienolides as well as of bufotenine derivatives. Tadpoles of both species exhibited a different pattern: extracts from B. arenarum tadpoles contained only dehydrobufotenine, but those from B. bufo tadpoles bufotoxin and two alkylamines. Melanophryniscus toads appear not to be able to compensate the high variability of toxic skin alkaloids by producing defensive bufadienolides. [Copyright &y& Elsevier]

Abstract: Zhaoermia mangshanensis (formerly Trimeresurus mangshanensis, Ermia mangshanensis) represents a monotypic genus of pitviper known only from Mt Mang in China''s Hunan Province, and is among the largest and most spectacular of Asian venomous snakes. The venom of Zhaoermia exhibits high coagulant activity on bovine and human fibrinogen and human plasma, high phosphodiesterase and arginine ester hydrolytic activity, and moderate to low l-amino acid oxidase, kallikrein, caseinolytic, phospholipase A2 (PLA2), haemorrhagic and myotoxic activities. The approximate i.p. LD50 of the venom in mice was estimated to be 4mg/kg. We purified the major toxin of Zhaoermia venom by gel-filtration, cation-exchange chromatography and HPLC. The toxin, a homodimer with an experimental monomeric mass of 13,972Da, induced edema and myonecrosis in mice, but was devoid of detectable PLA2 catalytic activity. Its complete amino acid sequence is composed of 121 amino acid residues cross-linked by seven disulfide bridges, and shows more than 80% identity to two Lys49-PLA2s from distantly related Asian pitvipers, Protobothrops mucrosquamatus and Calloselasma rhodostoma. Phylogenetic analysis of the novel toxin, zhaoermiatoxin, confirmed that it is rooted within a comprehensive sample of Lys49-PLA2s despite having an arginine residue in position 49, suggesting a secondary Lys49→Arg substitution which did not alter the catalytic inactivity of the molecule. [Copyright &y& Elsevier]

Abstract: Toads belonging to the genus Melanophryniscus contain toxic alkaloids in their skin. From six locations in south-eastern Uruguay 81 specimens of Melanophryniscus montevidensis were collected. In whole animal methanolic extracts of individual specimens, alkaloids of the pumiliotoxin (PTX) group and indolizidines were identified by gas chromatography/mass spectrometry; the predominant component PTX 251D was assayed quantitatively. The PTX-content of the various toad populations was found to be highly variable among individual specimens as well as among the populations. Very high levels of PTX 251D were detected in toads of the western part of the collection area, whereas very low levels of this alkaloid were assayed in toads near the Brazilian border. Remarkably high concentrations of the non-alkaloid hydroquinone were found to be present in all toads. The analysis of extracts from 125 arthropod samples (Arachnida and Insecta, including termites, ants and beetles), which may represent a potential food source, revealed no alkaloids of the PTX group. [Copyright &y& Elsevier]

Abstract: Butterflies of the Danaidae family are considered to be toxic or distasteful due to the presence of cardiac glycosides sequestered from their larval food plants. Alcoholic extracts of specimens of Danaus chrysippus aegyptius and Amauris ochlea ochlea from southern Africa (Namibia, S.-Africa, Mozambique) were analyzed by thin-layer chromatography for these cardenolides. But only 4 of 75 specimens of D. chrysippus aegyptius contained trace amounts, all others including 13 specimens of A. ochlea ochlea were negative. Genetic analysis of the ouabain binding site of the Na+, K+-ATPase revealed that both species do not present an amino acid replacement at the position 122, which otherwise makes the enzyme insensitive to cardenolides suggesting that other strategies of toxin tolerance must have been developed. [Copyright &y& Elsevier]

Abstract: The two major alkaloids, samandarine and samandarone, were identified in the skin secretion of individual specimens from two populations of the European fire salamander (Salamandra salamandra terrestris) by gas chromatography/mass spectrometry. High intraspecific variability in the ratio of both alkaloids was observed, but also in individual specimens over a period of 4 months suggesting separate metabolic pathways of the compounds. Alkaloid synthesis appears to take place also in liver, testes and ovaries, whereas the larvae of the salamanders are entirely free of alkaloids. [Copyright &y& Elsevier]

An analogue of tetrodotoxin (TTX), 11-oxoTTX, was semi-purified from the red-spotted newt, Notophthalmus viridescens, and identified by ESI-MS and 1H NMR spectra. The levels of TTX, 11-oxoTTX and 6-epiTTX in early stage of development (efts) of this newt were investigated by a post-column fluorescent-HPLC system, and compared with those of adult newts. The level of 11-oxoTTX in both of adults and efts were remarkably high, almost close to those of TTX, while 6-epiTTX was a minor component in both stages. The level of 6-epiTTX in efts (1.8±1.3 μg/g, SD, n=10) was significantly larger than that in adults (0.51±0.26 μg/g, SD, n=12) (p<0.05), while no significant difference was observed in the levels of TTX and 11-oxoTTX between efts (13±7.4 and 9.1±5.6 μg/g) and adult newts (16±6.3 and 13±6.2 μg/g, respectively) (p>0.05). [Copyright &y& Elsevier]

Biochemical and biological activities of a venom sample from a recently discovered new genus and species of pitviper from Vietnam, Triceratolepidophis sieversorum, were assayed and compared with those of five other viperid snakes (Bothrops asper, Crotalus atrox, Protobothrops flavoviridis, Trimeresurus insularis, and Vipera ammodytes). The venom had high casein hydrolysis, arginine ester hydrolysis and haemorrhagic activities, lacked measurable phosphodiesterase and l-amino acid oxidase activities, and had no procoagulant activity on either bovine fibrinogen or human plasma. Other enzymatic activities (phospholipase A2, kallikrein) were moderate. The approximate i.p. LD50 (mice) of the venom is about 5–6 mg/kg. [Copyright &y& Elsevier]

Abstract: In two species of meloid beetles, Hycleus oculatus and Hycleus tinctus, from southern Africa, cantharidin and demethylcantharidin (palasonin) were assayed quantitatively. For cantharidin the mean value per specimen was about 1mg for H. oculatus and 0.2mg for H. tinctus, the mean palasonin concentration was 20 (H. oculatus) and 12 times (H. tinctus) lower, respectively. However, considerable individual variation in the cantharidin concentration was observed and values of more than 6mg of this compound per beetle were measured pointing to the high risk of severe and even fatal poisoning when ingesting these insects. [Copyright &y& Elsevier]

Abstract: Tetrodotoxin (TTX) was quantitatively assayed in six specimens of semi- adult blue-ringed octopus, Hapalochlaena maculosa, by a post-column fluorescent-HPLC system. TTX was found to be present in all body parts, e.g. in high concentrations in the arms followed by the abdomen and cephalothorax. The toxin is not associated exclusively with the posterior salivary gland. [Copyright &y& Elsevier]

Abstract: Ten venoms from marine cone snails were tested for ichthyotoxic effects on zebra fish (Brachydanio rerio) when added to the water. Only two venoms, from Conus capitaneus and Conus episcopatus, produced lethal effects at high concentrations (50–300μg/ml) within 20–90min. No sedative or hypnotic symptoms were observed. The experiments confirm that Conus venoms exert a quick and prompt activity only by parenteral injection into the prey as it is performed by the snail. [Copyright &y& Elsevier]

Tetrodotoxin (TTX) and its analogues occur in a wide range of marine animals but also in terrestrial vertebrates such as frogs, toads and newts. Despite numerous studies on TTX in New World newts ( Notophthalmus viridescens, Taricha spp.), few data only exist for Asian newts. Methanolic extracts of newts from China ( Cynops orientalis , Pachytriton labiatus , Paramesotriton chinensis ), Vietnam ( Paramesotriton deloustali, P. guangxiensis ), and Laos ( Laotriton laoensis ) were analyzed by liquid-chromatography-fluorescent detection (LC-FLD) and mass-spectrometry (LC-MS). In all species, variable amounts of TTX were detected, in most specimens also TTX-analogues like 6- epi TTX, in C. orientalis 11-oxoTTX, confirming the presence of these toxins in modern Asian newts. [ABSTRACT FROM AUTHOR]

A useful approach to deepen our knowledge about the origin and evolution of venom systems in Reptilia has been exploring the vast biodiversity of this clade of vertebrates in search of orally produced proteins with toxic actions, as well as their corresponding delivery systems. The occurrence of toxins in anguimorph lizards has been demonstrated experimentally or inferred from reports of the toxic effects of the oral secretions of taxa within the Varanidae and Helodermatidae families. In the present study, we have focused on two alligator lizards of the Anguidae family, the Mexican alligator lizard, Abronia graminea , and the red-lipped arboreal alligator lizard, A. lythrochila. In addition, the fine morphology of teeth of the latter species is described. The presence of a conserved set of proteins, including B-type natriuretic peptides, cysteine-rich secretory proteins, group III phospholipase A 2 , and kallikrein, in submandibular gland extracts was demonstrated for both Abronia species. These proteins belong to toxin families found in oral gland secretions of venomous reptile species. This finding, along with previous demonstration of toxin-producing taxa in both paleo- and neoanguimorpha clades, provides further support for the existence of a handful of conserved toxin families in oral secretions across the 100+ million years of Anguimorpha cladogenesis. [Display omitted] • Proteomic analyses of submandibular gland extracts of two alligator lizards of the Anguidae family are reported. • A conserved set of putative toxins was found in the submandibular gland extracts of Abronia lythrochila and A. graminea. • Toxins evolved in oral secretions of paleo- and neoanguimorpha over more than 100 million years of Anguimorpha cladogenesis. • Electron microscopy of pleurodont teeth of A. lythrochila showed no sign of groove, external opening or striations. • Assessing the role toxins play in the ecology of extant anguimorph lizards deserves functional studies in natural prey. [ABSTRACT FROM AUTHOR]

Abstract: Conotoxins from the venom of marine cone snails (genus Conus) represent large families of proteins exhibiting a similar precursor organization, but highly diverse pharmacological activities. A directed PCR-based approach using primers according to the conserved signal sequence was applied to investigate the diversity of conotoxins from the O-superfamily. Using 3′ RACE, cDNA sequences encoding precursor peptides were identified in five Conus species (Conus capitaneus, Conus imperialis, Conus striatus, Conus vexillum and Conus virgo). In all cases, the sequence of the signal region exhibited high conservancy, whereas the sequence of the mature peptides was either almost identical or highly divergent among the five species. These findings demonstrate that beside a common genetic pattern divergent evolution of toxins occurred in a highly mutating peptide family. [Copyright &y& Elsevier]

A case of Vipera berus (European adder) snake bite to the forehead is reported, which caused extensive oedema of the head and trunk and petechial haemorrhages. These resolved over several days but there was a persistent unilateral facial frontalis muscle paresis and ptosis most likely due to the location of the bite in the left fronto-temporal area. [Copyright &y& Elsevier]

To cope with toxic metabolites plants use for defence, herbivorous insects employ various adaptive strategies. For oviposition, the fruit fly Dacus siliqualactis (Tephritidae) uses milkweed plants of the genus Gomphocarpus (Asclepiadaceae) by circumventing the plant's physical (gluey latex) and chemical (toxic cadenolides) defence. With its long, telescope-like ovipositor, the fly penetrates the exo- and endocarp of the fruit and places the eggs on the unripe seeds located in the centre of the fruit. Whereas most plant parts contain high concentrations of cardenolides such as gomphoside, calotropin/calacatin and gomphogenin, only the seeds exhibit low cardenolide levels. By surmounting physical barriers (fruit membranes, latex), the fly secures a safe environment and a latex-free food source of low toxicity for the developing larvae. One amino acid substitution (Q111V) at the cardenolide binding site of the fly's Na + , K + -ATPase was detected, but the significance of that substitution: reducing cardenolide sensitivity or not, is unclear. However, poisoning of the larvae by low levels of cardenolides is assumed to be prevented by non-resorption and excretion of the polar cardenolides, which cannot passively permeate the midgut membrane. This example of an insect-plant interaction demonstrates that by morphological and behavioural adaptation, a fruit fly manages to overcome even highly effective defence mechanisms of its host plant. [ABSTRACT FROM AUTHOR]

Some butterflies and moths sequester and retain noxious phytochemicals for defence against predators. In the present study, three moth species, the garden tiger moth, Arctia caja , the death hawk moth, Acherontia atropos , and the oleander hawk moth, Daphnis nerii , were tested whether they sequester alkaloids from their host plants. Whereas A. caja consistently sequestered atropine from Atropa belladonna, also when atropine sulfate was added to the alkaloid-free diet of the larvae, A. atropos and D. nerii were found to be unable to sequester alkaloids, neither atropine nor eburnamenine from Vinca major , respectively. Instead of acquiring toxicity as chemical defence, nocturnal lifestyle and cryptic attitudes may improve their chances of survival. [Display omitted] • Larvae of three moth species were reared on host plants containing alkaloids. • One of them, Arctia caja , sequesters and stores the alkaloid atropine. • The moth may achieve chemical protection against predators. • Two other moths, Acherontia atropos and Daphnis nerii do not sequester alkaloids. • Therefore, they lack toxic alkaloids useful for chemical defense. [ABSTRACT FROM AUTHOR]

Based on its phylogenetic relationship to monitor lizards (Varanidae), Gila monsters (Heloderma spp.), and the earless monitor Lanthanotus borneesis , the Chinese crocodile lizard, Shinisaurus crocodilurus , has been assigned to the Toxicofera clade, which comprises venomous reptiles. However, no data about composition and biological activities of its oral secretion have been reported. In the present study, a proteomic analysis of the mandibular gland of S. crocodilurus and, for comparison, of the herbivorous Solomon Island skink Corucia zebrata , was performed. Scanning electron microscopy (SEM) of the teeth from S. crocodilurus revealed a sharp ridge on the anterior surface, but no grooves, whereas those of C. zebrata possess a flattened crown with a pointed cusp. Proteomic analysis of their gland extracts provided no evidence of venom-derived peptides or proteins, strongly supporting the non-venomous character of these lizards. Data are available via ProteomeXchange with identifier PXD039424. [Display omitted] • A proteomic analysis of the mandibular glands of Shinisaurius crocodilurus and Corucia zebrata , was performed. • Scanning electron microscopy of S. crocodilurus' teeth revealed a sharp ridge on the anterior surface, but no grooves. • Scanning electron microscopy of C. zebrata teeth showed a flattened crown with a pointed cusp. • Proteomic analysis of gland extracts of S. crocodilurus and C. zebrata showed absence of venom-derived peptides or proteins. • Our results strongly support the non-venomous character of both S. crocodilurus and C. zebrata. [ABSTRACT FROM AUTHOR]

Abstract: Efts and adult specimens (n = 142) of the red-spotted newt Notophthalmus viridescens from various locations in Canada and USA were analyzed for the presence of tetrodotoxin (TTX) and of its analogues 6-epitetrodotoxin and 11-oxotetrodotoxin. Considerable individual variations in toxin levels were found within and among populations from New Hampshire, New York, Pennsylvania, and Virginia ranging from non-detectable to 69 μg TTX per g newt. TTX and its analogues were absent in efts and adults from various locations in the Canadian province Nova Scotia, the northernmost distribution of the newt, and in adults from Florida. Newts kept in captivity for several years and reared on toxin-free diet lost their toxicity. Bayesian and maximum likelihood phylogenetic analysis of specimens from the various populations using three phylogenetic markers (COI, ND2 and 16S RNA) revealed that populations from the northern states of the USA and Canada are genetically homogenous, whereas the newts from Florida exhibited a much higher level of genetic divergence. An exogenous source of TTX in the newts either via the food chain or by synthesis of symbiotic bacteria is suggested to explain the high variability and lack of TTX in certain populations. [Copyright &y& Elsevier]

Abstract: From six Conus species (Conus coronatus, Conus lividus, Conus mozambicus f. lautus, Conus pictus, Conus sazanka, Conus tinianus) collected off the eastern coast of South Africa the venoms were analyzed using MALDI-TOF mass spectrometry. Between 56 and 151 molecular masses most in a range of 1000 to 2500 Da, were identified. Among the six venoms, between 0 and 27% (C. coronatus versus C. sazanka) of the peptide masses were found to be similar. In a study on venoms from 6 Conus species collected in the Philippines, the percentage of identical masses was between none and 9% only. The venoms from the South African Conus species antagonized the rat neuronal nicotinic acetylcholine receptors (nAChRs) α3β2, α4β2, and α7, except for C. coronatus venom that blocked the α4β2 and α7 nAChRs only. HPLC-fractionation of C. tinianus venom led to the isolation of a peptide that is active on all three receptor subtypes. It consists of 16 amino acid residues cross-linked by two disulfide bridges as revealed by de novo sequencing using tandem mass spectrometry: GGCCSHPACQNNPDYC. Posttranslational modifications include C-terminal amidation and tyrosine sulfation. The new peptide is a member of the α-conotoxin family that are competitive antagonists of nAChRs. Phylogenetic analysis of the 16S RNA from numerous Conus species has clarified the evolutionary position of endemic South African Conus species and provided the first evidence for their close genetic relationships. [ABSTRACT FROM AUTHOR]

Abstract: The venom from the solitary bee Osmia rufa (Hymenoptera: Megachilidae) was analyzed using mass spectrometry (MS)-based techniques. Sensitive proteomic methods such as on-line LC–ESI-MS and nanoESI-MS analyses revealed more than 50 different compounds with molecular masses ranging from 400 to 4000Da. The major component has a monoisotopic molecular mass of 1924.20Da and its amino acid sequence was elucidated by de novo sequencing using tandem mass spectrometry and Edman degradation. This 17-residue cysteine-free peptide, named osmin, shows some similarities with the mast cell degranulation (MCD) peptide family. Free acid and C-terminally amidated osmins were chemically synthesized and tested for antimicrobial and haemolytic activities. The synthetic C-amidated peptide (native osmin) was found to be about three times more haemolytic than its free acid counterpart, but both peptides are much less lytic than melittin from social bee venom. Preliminary antimicrobial and antifungal tests indicate that both peptides are able to inhibit bacterial and fungal growth at micromolar concentrations. [Copyright &y& Elsevier]