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Amphinomids, more commonly known as fireworms, are a basal lineage of marine annelids characterized by the presence of defensive dorsal calcareous chaetae, which break off upon contact. It has long been hypothesized that amphinomids are venomous and use the chaetae to inject a toxic substance. However, studies investigating fireworm venom from a morphological or molecular perspective are scarce and no venom gland has been identified to date, nor any toxin characterized at the molecular level. To investigate this question, we analyzed the transcriptomes of three species of fireworms--Eurythoe complanata, Hermodice carunculata, and Paramphinome jeffreysii--following a venomics approach to identify putative venom compounds. Our venomics pipeline involved de novo transcriptome assembly, open reading frame, and signal sequence prediction, followed by three different homology search strategies: BLAST, HMMER sequence, and HMMER domain. Following this pipeline, we identified 34 clusters of orthologous genes, representing 13 known toxin classes that have been repeatedly recruited into animal venoms. Specifically, the three species share a similar toxin profile with C-type lectins, peptidases, metalloproteinases, spider toxins, and CAP proteins found among the most highly expressed toxin homologs. Despite their great diversity, the putative toxins identified are predominantly involved in three major biological processes: hemostasis, inflammatory response, and allergic reactions, all of which are commonly disrupted after fireworm stings. Although the putative fireworm toxins identified here need to be further validated, our results strongly suggest that fireworms are venomous animals that use a complex mixture of toxins for defense against predators. [ABSTRACT FROM AUTHOR]

An impressive biodiversity (>10,000 species) of marine snails (suborder Toxoglossa or superfamily Conoidea) have complex venoms, each containing approximately 100 biologically active, disulfide-rich peptides. In the genus Conus, the most intensively investigated toxoglossan lineage (∼500 species), a small set of venom gene superfamilies undergo rapid sequence hyperdiversification within their mature toxin regions. Each major lineage of Toxoglossa has its own distinct set of venom gene superfamilies. Two recently identified venom gene superfamilies are expressed in the large Turridae clade, but not in Conus. Thus, as major venomous molluscan clades expand, a small set of lineage-specific venom gene superfamilies undergo accelerated evolution. The juxtaposition of extremely conserved signal sequences with hypervariable mature peptide regions is unprecedented and raises the possibility that in these gene superfamilies, the signal sequences are conserved as a result of an essential role they play in enabling rapid sequence evolution of the region of the gene that encodes the active toxin. [ABSTRACT FROM AUTHOR]

Abstract: There are over 10,000 species of venomous marine molluscs, the vast majority of these, which are generally referred to as “turrids”, are traditionally assigned to a single family, Turridae (). Here, we provide an initial molecular analysis of the type genus of the family, Turris Röding, 1798, thought to be among the most well characterized groups in the family. We show that the type genus is not monophyletic. We analyzed specimens conventionally assigned to 9 different Turris species using molecular markers, combined with the shell morphology and radular anatomy whenever feasible. The results suggest that species assigned to the genus Turris, provisionally assigned to two different subgenera are not monophyletic. Five previously described species belong to the subgenus Turris (s.s.) Röding 1798: Turris babylonia, (Linne, 1758), Turris grandis, (J. E. Gray, 1834), Turris dollyae, (, Turris normandavidsoni ( and Turris spectabilis (Reeve, 1843). With a change in species designation, Turris assyria (formerly T. babylonia1010) is added to a well-defined clade, which is in turn more closely related to Lophiotoma and Gemmula species than to the other five Turris species. We show that these five species conventionally assigned to Turris do not belong in the same subgenus, and form a clade provisionally designated as Annulaturris: Turris annulata, (Reeve, 1843), Turris undosa, (Lamarck, 1816), Turris cristata, (Vera-Peláez, Vega-Luz, and Lozano-Francisco 2000) Turris cryptorrhaphe (G. B. Sowerby, 1825) and Turris nadaensis (Azuma, 1973). Implications of the molecular phylogenetic results and its correlation with radular morphology are discussed. [Copyright &y& Elsevier]

Abstract: Hydra have been classical model organisms for over 250 years, yet little is known about the toxins they produce, and how they utilize these toxins to catch prey, protect themselves from predators and fulfill other biological roles necessary for survival. Unlike typical venomous organisms the hydra allomonal system is complex and “holistic”, produced by various stinging cells (in the hunting tentacles and body ectoderm) as well as by non-nematocytic tissue. Toxic proteins also fulfill novel, non-allomonal roles in hydra. This review described the toxins produced by hydra within the context of their biology and natural history. Hydra nematocyst venom contains a high-molecular weight (>100kDa) hemolytic and paralytic protein and a protein of ∼30kDa which induces a long-lasting flaccid paralysis. No low-molecular weight toxicity is observed, suggesting the lack of “classical” 4–7kDa neurotoxins. The occurrence of a potent phospholipase activity in the venom is supported by the detection of several venom-like phospholipase A2 genes expressed by hydra. Hydra also produce toxins which are not part of the nematocyst venom. In the green hydra, Hydralysins, a novel family of Pore-Forming Proteins, are secreted into the gastrovascular cavity during feeding, probably helping in disintegration of the prey. Other putative non-nematocystic “toxins” may be involved in immunity, development or regulation of behavior. As the first venomous organism for which modern molecular tools are available, hydra provide a useful model to answer many outstanding questions on the way venomous organisms utilize their toxins to survive. [Copyright &y& Elsevier]

Venoms are rich mixtures of mainly peptides and proteins evolved by nature to catch and digest preys or for protection against predators. They represent extensive sources of potent and selective bioactive compounds that can lead to original active ingredients, for use as drugs, as pharmacological tools in research and for the biotechnology industry. Among the most fascinating venomous animals, marine snails offer a unique set of pharmacologically active components, targeting a wide diversity of receptors and ion channels. Recent advances still continue to demonstrate their huge neuropharmacological potential. In the quest for interesting pharmacological profiles, researchers face a vast number of venom components to investigate within time and technological constraints. A brief perspective on marine snail venom''s complexity and features is given followed by the different discovery strategies and pharmacological approaches, exemplified with some recent developments. These advances will hopefully help further uncovering new pharmacologically important venom molecules. [Copyright &y& Elsevier]

Abstract: The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC50 =2 µg/mL vs. 12 µg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (≤20 °C) and dramatically lost at high temperature (≥60 °C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH≤4). Interestingly enough, however, its activity was not significantly affected even at the highest pH environment tested (pH≤12) in the present study. Additionally, hemolytic activity of the venom was examined using the erythrocytes of cat, dog, human, rabbit and rat. Venom concentration-dependent hemolysis could be observed from 10 µg/mL of protein equivalents or higher with variable potencies in different species, among which dog erythrocyte was the most susceptible to the venom (EC50 =151 µg/mL). SDS-PAGE analysis of N. nomurai venom showed the molecules of 20–40 kDa and 10–15 kDa appeared to be the major protein components of the venom. [Copyright &y& Elsevier]

Marine stingers hospitalize approximately 100 people annually in tropical Australian waters, and are known to have caused at least 73 fatalities. Elsewhere in the tropical and temperate seas of the world, marine stingers pose a similar threat to human safety, and reported sting numbers are on the rise. Lycra body suits ("stinger suits") have been used for stinger protection since the early 1980s, but have not been formally tested as a barrier against Irukandji (Carukia barnesi) tentacles. Other products are being used and developed; however, no safety standards currently exist for this widely used form of protective equipment. Eight products were tested with live C. barnesi: a Lycra stinger suit used by Surf Life Saving, a product developed by ROBIS Pty. Ltd. and marketed as "The Stinger Suit", three different styles of nylon pantyhose, two sport products designed to "wick away" moisture and keep the wearer cooler, and a 0.5-mm neoprene wetsuit. Products were evaluated for seven common concerns relating to safety and practical wearability. Primary concerns, i.e., those relating to performance of the fabric in preventing stings, include: ease of penetration by jellyfish tentacles, adherence of tentacles or body to fabric, and potential for crushing through the fabric. Secondary concerns, i.e., those relating to overall usage as stinger-preventative clothing, include: durability or integrity of the barrier, whether the product is available as a one-piece garment, heat-retention properties, and product cost. In general, the tighter the fabric weave, the better tentacle exclusion, and the smoother the fabric, the more resistant to adherence. Lycra is vulnerable to crushing of tentacles through the fabric, but appears to be the best choice for routine-use stinger-protective clothing. Recommendations are made for safe use of protective clothing, as a basis for development of an Australian Standard in protective clothing for marine stinger safety. [ABSTRACT FROM AUTHOR]

The article presents a study on the symbiotic relationship that exists between parthenopid crab Zebrida adamsii and the sea urchin Toxopneustes found in the Gulf of Mannar, India. Topics discussed include the planting of the Cymodocea seagrass species under the sand beds in simulating the natural environment of the sea urchins, the host specifity assessment of the association of the crab with T. pileolus sea urchin, and the venom contained by the Toxopneustes genus of sea urchin.