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A non-toxic protein (TsNTxP) from Tityus serrulatus scorpion venom has been shown to be an efficient immunogen and anti-TsNTxP antibodies recognize and neutralize the effect of Tityus serrulatus venom [Chavez-Olortegui et al., 1997. Toxicon 35, 213-221]. With the purpose of studying the organization of the gene that code for this protein, we have isolated a full length cDNA clone for TsNTxP from a...
Functional nematocysts of one specific morphological class, the penetrant microbasic mastigophores, were isolated from the sea anemone, Aiptasia pallida. These nematocysts contain a multicomponent venom composed of several proteins, including those with neurotoxic, hemolytic, and lethal activities. Hemolytic activity is produced by at least three synergistic venom proteins. One of these proteins is...
The purified β phospholipase A 2 (PLA 2 ; EC 3.1.1.4) (PLA 2 ) from sea anemone (Aiptasia pallida) nematocysts is larger and more labile than other known venom PLA 2 s. In common with all other known venoms and most secretory PLA 2 s, the β PLA 2 requires mM Ca 2+ for optimal activity and is surface-activated by aggregated lipids such as...
The toxic dinoflagellate Alexandrium minutum T1 was isolated from southern Taiwan in February 1996, grown under various environmental and nutritional conditions, and then examined for growth, toxicity, and toxin profile. It was found that the optimal environmental conditions for cell growth and toxin production of A. minutum T1 was as follows: temperature 25 o C, pH<space>7.5, light...
In order to elucidate the toxin composition of the freshwater puffer in Bangladesh, about 230 specimens of Tetraodon sp. were collected from 1997 to 1999 and extracted. After partitioning the toxins between an aqueous layer and a 1-butanol layer, the toxin in the aqueous layer was characterized as paralytic shellfish poison (PSP) (data not shown), while the toxin in the 1-butanol layer was identified...
The neutralization of botulinum toxin serotype A with polyclonal equine antitoxin was studied in isolated mouse hemidiaphragms and compared to the same action in live mice. The biological activity of the toxin in the isolated muscle could be markedly reduced with excess antitoxin, estimated as 3:1 molar ratios of IgG Ab:toxin or better. Toxin neutralization in vivo required higher ratios of Ab:toxin,...
We have determined that the mammalian uridine diphospho-N-acetyl-d-galactosamine:polypeptide N-acetylgalactosaminyltransferase T1 (EC 2.4.1.41) has the appropriate acceptor substrate specificity to recognize the non-glycosylated form of contulakin-G (ZSEEGGSNATKKPYIL-OH where Z=pyroglutamic acid) and to transfer GalNAc to the peptide. Both [Thr 10 ] contulakin-G and a pre-contulakin-G...
Gyroxin fails to modify in vitro release of labelled dopamine and acetylcholine from rat and mouse striatal tissue. Gyroxin is a thrombin-like peptide with amidasic, esterasic and fibrinogenolitic activities, found in the venom of snakes like Lachesis muta muta and Crotalus durissus terrificus. Intravenous injections of small doses of gyroxin induce a typical barrel rotation behaviour that has been...
Metarhizium anisopliae produces a family of cyclic peptide toxins, destruxins (DTXs), which exhibit various insecticidal activity. Four major DTXs have been separated by HPLC and identified by the liquid chromatography electrospray mass spectrometry (LC-ESI-MS) methods. Strain F061 of M. anisopliae produced large amounts of (DTXs), especially DTX-A (12.84+/-0.04μg/ml), DTX-B (66.89+/-2.57μg/ml) and...
We report here the isolation by a two-step chromatographic procedure of two new toxins from the South American scorpion Tityus bahiensis. Their amino-acid sequences and some of their biological features were established. The two toxins have different biological properties. Toxin TbIT-I had almost no activity or pharmacological effects in vertebrate tissues whereas it was lethal to house flies (LD50...
A strain of Cylindrospermopsis (Cyanobacteria) isolated from a fishpond in Thailand was examined for its taxonomy based upon morphology and 16S rRNA gene sequence. It was also examined for production of the hepatotoxic cyanotoxin called cylindrospermopsin (CYN) and deoxycylindrospermopsin (deoxy-CYN). The strain (CY-Thai) was identified as C. raciborskii (Woloszynska) Seenaya and Subba Raju based...
The brackish water cyanobacterium Nodularia spumigena produce the hepatotoxic cyclic pentapeptide nodularin. Intoxications for both human as well as animal may arise when water reservoirs are contaminated with potentially toxic Nodularia species. Here, results of three independent methods for the determination of nodularin in different strains of N. spumigena are presented. The results obtained with...
The plant toxin ricin consists of two disulfide-linked polypeptides with different functions. The A-chain enters the cytosol and inactivates the ribosomes enzymatically, whereas the B-chain has lectin properties and binds to carbohydrates at the cell surface. This binding is a requirement for translocation of the A-chain to the cytosol. The bound toxin is endocytosed and transported retrograde through...
Diphtheria toxin is one of the most extensively studied and well understood bacterial toxins. Ever since its discovery in the late 1800's this toxin has occupied a central focus in the field of toxinology. In this review, I present a chronology of major discoveries that led to our current understanding of the structure and activity of diphtheria toxin.
Shiga toxin and Shiga-like toxins belong to the group of protein toxins which have a moiety that binds to the cell surface and another enzymatically active moiety that after entry into the cytosol inhibits protein synthesis enzymatically. The toxins can also cause apoptosis by mechanisms that may be different from the effect on the protein synthesis machinery. Shigella dysenteriae, some strains of...
Sixteen different genes were cloned from the venomous glands of Centruroides sculpturatus Ewing using RNA extracted from scorpions collected in Tucson, Arizona. Based on the amino acid sequence similarities of the proteins coded by these genes, all together there are 22 different structural components in this venom, thought to be specific for Na + -channels. The genes reported contain signal...
By means of high performance liquid chromatography (HPLC) the soluble venom of the Amazonian scorpion Tityus cambridgei was fractionated into over 50 different components. Four toxic and/or lethal peptides to mice were obtained in pure form and sequenced. Mass spectrometry analysis showed molecular weights of 7310, 7151, 7259 and 7405, respectively, for toxins Tc48a, Tc49a, Tc54 and Tc49b. The N-terminal...
Haemolytic activity against mammalian erythrocytes was detected in very low concentrations of saliva from the octopus Eledone cirrhosa. It was not caused by any previously identified component of this saliva. The activity was slightly inhibited by trypsin and more drastically by chymotrypsin.Locust bioassay was used to test HPLC fractions isolated from E. cirrhosa saliva. An LD 50 of...
Among the different scorpion species, Buthus martensi Karsch (BmK), a widely distributed scorpion species in Asia, has received a lot of attention. Indeed, over the past decade, more than 70 different peptides, toxins or homologues have been isolated and more peptides are probably still to be revealed. This review is focusing on the many peptides isolated from the venom of this scorpion, their targets,...
We determined the seasonal distribution of paralytic shellfish toxins (PSTs) and PST producing bacteria in >15, 5-15, and 0.22-5μm size fractions in the St Lawrence. We also measured PSTs in a local population of Mytilus edulis. PST concentrations were determined in each size fraction and in laboratory incubations of sub-samples by high performance liquid chromatography (HPLC), including the rigorous...
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