Surface activity of polypeptide toxins isolated from Anemonia sulcata.

Circular dichroism spectra and surface activities are reported for toxins II and III isolated from Anemonia sulcata. Toxin II is highly surface active and as a result possesses a synergistic effect with phospholipase A2. In complete contrast, toxin III lacks detectable surface activity. The presence of sodium dodecyl sulfate (2.5 mg.ml-1) failed to trigger large conformation changes in both toxins II and III. From a comparison of the sequences of toxins II and III it is suggested that the hydrophobic region 17-27 is responsible for the surface activity of toxin II.

Amino-acid sequence of toxin I from Anemonia sulcata.

Toxin I from Anemonia sulcata, a major component of the sea anemone venom, consists of 46 amino acid residues which are linked by three disulfide bridges. The [14C]carboxymethylated polypeptide was sequenced to position 29 by automated Edman degradation. The remaining sequence was determined from cyanogen bromide peptides and from tryptic peptides of the citraconylated [14C]carboxymethylated toxin. Toxin I is homologous to toxin II from Anemonia sulcata and to anthopleurin A, a toxin from the sea anemone Anthopleura xanthogrammica. These toxins constitute a new class of polypeptide toxins. No significant homologies exist with toxin III from Anemonia sulcata nor with known sequences of neurotoxins or cardiotoxins of various origin.

Biochemistry and applications of aprotinin, the kallikrein inhibitor from bovine organs.

The basic proteinase inhibitor from bovine organs, aprotinin (active ingredient of Trasylol) has been extensively studied with respect to its chemical, physical and biochemical properties and its inhibitory mechanism of action. It is widely used as a valuable tool for studying protein/protein interactions and protein conformation at the molecular level. There are numerous examples of the usefulness of aprotinin in biochemical and biomedical research. It has also become a valuable drug for the treatment of various diseases like, e.g. hyperfibrinolytic hemorrhage and traumatic-hemorrhagic shock. The purpose of this paper is threefold. It summarizes our present knowledge of the subject in various disciplines; it provides the active scientist with basic data for his experimental work; and above all it points the way to future directions of aprotinin research.

[Osteoporosis and pre- and postpartal heparin therapy]. / Osteoporose unter prä- und postpartaler Heparintherapie.

Multiple vertebral compression fractures occurred in the 33rd week of pregnancy in a breast-feeding mother receiving heparin (20,000-25,000 units/die over 5 months), for deep vein thrombosis. Osteoporosis under heparin therapy is a rare complication and this diagnosis was not made despite obvious clinical signs. It follows from this observation, that heparin therapy should be substituted by oral anticoagulant therapy and discontinued directly after delivery.

Purification and characterisation of four polypeptides with neurotoxic activity from Condylactis aurantiaca.

Four toxic polypeptides, Toxins I, II, III and IV were isolated in pure form from the sea anemone Condylactis aurantiaca (Actinaria). Toxin isolation was achieved by alcoholic extraction of the homogenised sea anemones, batchwise adsorption onto cation exchangers, gel filtration on Sephadex G-50 and G-25 and ion-exchange chromatography on SP-Sephadex and QAE-Sephadex. Toxins from Condylactis aurantiaca all contain between 49 and 51 amino acids. Their amino acid compositions were compared to those of the Anemonia sulcata toxins. The toxins were tested on the shore crab Carcinus maenas by intramusclar injection. Crabs react highly sensitively to sea anemone toxins with muscle cramps and paralysis. For Condylactis toxins LD100 ranges from 2 to 6.6 mug/kg Carcinus maenas.

Amino acid sequence of toxin III from Anemonia sulcata.

Toxin III, the smallest toxin component of the poison of the sea anemone Anemonia sulcata, is a polypeptide with 27 amino acids. Its structure is stabilized by three disulfide bridges. The amino acid sequence was determined by solid-phase Edman degradation of the aminoethylated derivative. The peptide was coupled to the carrier, porous glass, by thiourea bridges between the alpha-amino group of arginine-1 and the epsilon-amino group of lysine-26 and the isothiocyanate groups of the carrier. Another fraction of the polypeptide was bound by an acid-amide condensation of the C-terminal valine-27 with the aminopropyl group of the carrier. The sequence of toxin III has no regions homologous to the 47-residue toxin II. Comparison with the known partial sequence of toxin I, which contains 46 amino acids (Wunderer, G. & Eulitz, M., in preparation) also fails to reveal homologies.

Human Ile-Ser-bradykinin, identical with rat T-kinin, is a major permeability factor in ovarian carcinoma ascites.

Ascites from patients with metastatic ovarian carcinoma contains high amounts of an activity that increases vascular permeability, as easily detected by a rat skin test. Ascites was fractionated by gel permeation and reversed-phase high-performance liquid chromatographies. The fractions were analysed for permeability-increasing activity. In this way a peptide was isolated and identified as Ile-Ser-bradykinin by sequence and amino-acid analyses. It is identical with T-kinin which has previously been detected as a product of an acute-phase protein, T-kininogen, in rats but never in human material. The so far identified human kininogens, i.e. high- and low-molecular mass kininogens, can only release Met-Lys-bradykinin or its degradations products, as Ile-Ser-bradykinin is not a part of their structure. However, the present results provide evidence that the permeability factor Ile-Ser-bradykinin under certain conditions can be produced in considerable amounts also by human tissues.

[Action of toxin II isolated from the tentacles of sea anemones on the neuromuscular transmission on normal and botulin toxin inhibited frogs]. / Action de la toxine IL isolée des tentacules d'Anémone de mer sur la transmission neuro-musculaire de Grenouille normale et inhibée par la toxine botulique.

In our experimental conditions, toxin II from Anemonia sulcata restored Frog neuromuscular transmission blocked by botulinum toxin, type A.

Amino-acid sequence of a coelenterate toxin: toxin II from Anemonia sulcata.

Toxin II from Anemonia sulcata, the main component of the sea anemone venom, consists of 47 amino acid residues which are interconnected by three disulfide bridges. The S-aminoethylated polypeptide was coupled to activated glass beads and sequenced to position 33 by automated solid-phase Edman degradation. Blanks arising from anchor points and the rest of the sequence were determined from tryptic peptides of the [14C]carboxymethylated toxin. Toxin II shows no significant homologies with other known sequences of neurotoxins or cardiotoxins. It might constitute a new class of polypeptide toxins.

Sea anemone toxin:a tool to study molecular mechanisms of nerve conduction and excitation-secretion coupling.

The effects of polypeptide neurotoxin from Anemonia sulcata on nerve conduction in crayfish giant axons and on frog myelinated fibers have been analyzed. The main features of toxin action are the following: (i) the toxin acts at very low doses and its action is apparently irreversible. (ii) The toxin selectively affects the closing (inactivation) of the Na+ channel by slowing it down considerably; it does not alter the opening mechanism of the Na+ channel or the steady-state potassium conductance. (iii) The tetrodotoxin-receptor association is unaffected by previous treatment of the axonal membrane with the sea anemone toxin. (iv) Conversely, the sea anemone toxin can only associate with the membrane when the Na+ channel is open for Na+; it does not bind when the channel is previously blocked by tetrodotoxin. (v) Besides its effect on the action potential, the sea anemone toxin displays a veratridine-type depolarizing action at low Ca2+ concentration which can be suppressed by tetrodotoxin. The sea anemone toxin greatly stimulates the release of gamma-[3H]aminobutyric acid from neurotransmitter-loaded rat brain synaptosomes. The apparent dissociation constant of the neurotoxin-receptor complex in this system is 20 nM. The sea anemone toxin effect is antagonized by tetrodotoxin.

Ile-Ser-bradykinin is an aberrant permeability factor in various human malignant effusions.

In this study we provide evidence for the presence of the aberrant peptide, Ile-Ser-bradykinin, in various human malignant exudates. The peptide was detected by deproteinisation of the effusion, application to reversed-phase HPLC, collection of the fractions containing Ile-Ser-bradykinin (retention time 6.90 min), degradation with carboxypeptidase B, and rechromatography of the resulting des-Arg-Ile-Ser-bradykinin (des-Arg-ISB) (retention time 13.5 min). In addition, all positive samples were confirmed by amino acid analysis and most of them (7/8) by amino-acid sequencing. In malignant effusions from 8 patients out of a group of 113 patients, Ile-Ser-bradykinin was found in concentrations between 12 and 520 mumol. In 44 malignant effusions, Ile-Ser-bradykinin was suspected, but could not be confirmed by the required additional methods (amino-acid analysis, sequencing) because of its low concentration. Sixty eight benign effusions were negative for Ile-Ser-bradykinin.