Identification, partial purification and some properties

D~rrrrsa, M. E. sad Gees, P. w. (School of Physiology sad Pharmat~oWgy, University of New South Wales, Kemington, 2033, N.S .W., Australia) . Presynaptic and pastsynaptic effects of the venom of the Ats:traliaa tiger wake at the nauomttxvlar junction . Br. J. Plrarntae. ~9, 340, 1973 . Cetvea venom from ebe Australian tiger snake (TSV) has both pro- a~ post-synaptic etsacts st the ~uromaxvlarjuoctiom of toads. TSV blocked indirectly elicited muscle twitches v~i~hout affecting the compound action potential of the motor nerve or twitclxs elicited by direct stimulation. The depolarleation of muscle fibres caused by arbachol was inhtöited and the amplitude of miniature endplate potentials (mepps) reduced by TSV. The frequency of tnepps wan first inarased and then deaeased otter several hours in the venom (1 I+g per ml). Occasional, high frequency ~burtts' of mepps were observed. The quaatal content of endplate potentials (epPs) was reduced by TSV, often otter as initial increase. tiger snake antivenene counteracted the poatsynaptic, but not the presYnaptic efforts of TSV when they had developed. These results are in good aooordance with those teported by Karlsson et al. (Toxloar 10, 405,1972). C.Y.L. Stturrneaov, S. : A protease inhibitor in bee venom. Idrntiflcation, partial purification and soma properties. FEBS Lett. 33, 343 (1973) . Ben vt~ost of different sources was freed from high-molecular weight compounds by vacuum filtration agairut 0~9 M ammonium formate buffer. The material having passed the membrane was fractionated by gel filtration on Sephadex G 30. The fraction inhibiting processes, especially trypsin, appeared just behind the melittin peak. Its apparent molecular weight was about 9000. E.H . Curve, C. C. and Hv~tve, M. C. (Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan, China). Comparison of the presyttaptic actions of botulinum ' toxin and ß.bungarotoxin on neuromuscular transmission . Ttte wrttoas compared the presynaptic actions of type A butolinum toxin (ßoTX) and ß.bungarotoxin (ß-BuT?q on isolated phrrnicnerve-diaphragm preparations of the mouse and the rat and the chick bivrnter «wires muscle . The paralytic actions of both toxins are pre«ded by latency, antagonized by high con«ntrations of calcium or magnesium and by deficiency of calcium, aaelerated by high frequency of nerve stimulation and retarded by decrease of temperature. It is concluded that the paralytic action of BoTX as well as ß-BuTX takes pla« in two pro«sses : first, binding with their respective target sites and second, the inhibitory changes of the target macromolecule of the nerve terminals leading to failure of transmitter release. The latter pro«ss is retarded more than the first one by low calcium, high magnesium or low temperature . End-plate potentials were depressed and the aucoessive decline of their amplitude during train of pulses was abolished by both toxins . In contrast to the Initial facilitatory action after ß-BuTX, BoTX has no sign of facilitation such as increase of the frequency of miniature end-plate potrntial, increase of quantal oontrnt of end-plate potrntial and oocurren« of spontaneous fasciculations. The two toxins show mutual antagonism especially when ß-BuTX is added before or simultaneously with BoTX . C.Y.L. Hestttreo~ro, Y, and Astttn~, K. (Laboratory of Marine Biochemistry, Faculty of Agriculture, University of Tokyo, Tokyo, Japan). Screening of toxic oorall and isolation of a toxic polypeptide from Conlopora app . Publs . Sere nrar. brol. Lab. 20, 703, 1973 . THe scaeeNtrw of eight species of Pacific corals has yielded some 20 specimens whose water-soluble extracts are toxic to mi« by i.p. igjection. From one species, Gon(opora sp., a purifiled toxin has been obtained by saline extraction of tissue followed by fractionation on CM~ellulose and Sephadex G-SO column chrome-. tography. The purified toxin appears to be a single homogeneous protein of molecular weight 9400, which is lethal to mi« on i.p . injection at a level of 0~5 mg per kg of mouse. This purified polypeptide exerts its lethal action rapidly (minutes to hours) with characteristic toxic sigru in mi« that include hypersensitivity, paralysis of hind limbs, stiffness of the entire body, and dyspnea with cyanosis. S.L.F. roxtcoN tsrr~ vet is