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Thermal stability of snake venom enzymatic activities
42
First A s i a - Pacific Congress
Non-divergence theory of evolution: amino acid sequence comparison of proteroglyphous snake venom components. N. TAMIVA(Department of Chemistry, Tohoku University, Sendai, Japan). THERE ARE several different proposals on the systematics of proteroglyphous snakes, namely sea snakes, cobras, kraits, coral snakes, etc. The author compared the amino acid sequences of neurotoxins and phospholipases in these snake venoms. The classification varies according to the kinds of proteins considered, similarly to the morphological taxonomy. It is usually assumed that each species evolved by divergence from a common ancestor. It is even assumed that all the organisms on the earth evolved from a single ancestor. The use of the same 20 L-amino acids and the common codon system by all the organisms (the unity of life) is taken as the evidence for the existence of such an ancestor. The author proposes to abandon the assumption. The living organisms on the earth exchange information through various mechanisms, namely through sex, hybridization, infection and symbiosis. With all these mechanisms, the information shuffling among the organisms is so efficient that the unity of life is achieved. The situation is similar to the language unification in human society. Every organism on the earth is an expression of a bunch of information pieces in the stream of information. Every protein molecule or every part of a protein molecule has its own history which does not necessarily coincide with those of the others in the same organism or in the same molecule. The ultimate source of new information is mutation, but the new combination of the information is the essential factor for evolution. With efficient information shuffling mechanisms, evolution becomes inevitable rather than accidental.
Paralytic shellfish poisoning in Singapore. C. T. T. TAN and E. J. D. LEE (Department of Pathology, Outram Road, Singapore 0316). THIS PAPERreports the first outbreak of paralytic shellfish poisoning from green mussels in Singapore amongst a group of foreign workers, which resulted in two deaths. Green mussels left over from the meal were recovered and identified as Perna viridis and analysis of the meat by a standardised mouse bioassay technique showed that there was approximately 186 mouse units of toxin per gram of mussel meat. Epidemiological investigations showed the presence of considerable planktonic debris in the water where the toxic mussels had been collected, but the plankton could not be typed as they had disintegrated by the time the samples of water had been collected. Post-mortem examinations were conducted on the two fatal cases. No specific post-mortem changes were found. An attempt was made to extract and demonstrate the toxin from the stomach and intestinal contents recovered at the post-mortem examinations. Using the same standardised mouse bioassay technique it was possible to demonstrate a lethal effect for one of the intestinal contents and to produce abnormal behaviour in the mice for the other three specimens. The successful demonstration of the toxin in such biological specimens would be important in establishing the diagnosis of paralytic shellfish poisoning in situations where the clinical history of ingestion is weak or unavailable.
Thermal stability of snake venom enzymatic activities. NGET-HONG TAN and CHON-SENGTAN (Department of Biochemistry, University of Malaya, Kuala Lampur, Malaysia). The thermal stability of L-amino acid oxidase, hyaiuronidase, alkaline phosphomonoesterase, 5'-nucleotidase, protease, arginine ester hydrolase, phosphodiesterase, acetylcholinesterase, phospholipase A and coagulant enzyme in venoms from Trimeresuruspurpureomaculatus, Calloslasmarhodostoma, Naja naja atra, Naja naja
sputatrix, Enhydrina schistosa, Bitis arietans, Vipera russelli, Agkistrodon piscivorous, Crotalus atrox, Ophiophagus hannah, Echis carinatus, Bungarus fasciatus and Dendroaspis jamesoni were investigated. The venom enzymatic activities were stable at 4°C in physiological saline: most enzymes retained full activity after 46 days incubation. On the other hand, venom enzymatic activities were much less stable in 0.05 M Tris buffer (pH 8.5), particularly the L-amino acid oxidase and hyaluronidase activities. At 37°C in physiological saline the enzymes gradually lost activity. It is interesting to note, however, that even after 39 days incubation at 37°C some venom solutions still retained considerable amounts of enzymatic activities. The venom enzyme activities were very stable at room temperature if the venoms were stored as powder form. There was negligible loss in enzymatic activities after storage of the venoms at room temperature for 1 month.
Comparative enzymology of Asian cobra venoms. NGET-HONG TAN, A. ARMUGAM and CHON-SENG TAN (Department of Biochemistry, University of Malaya, Kuala Lumpur, Malaysia). The enzymatic activities of twelve Asian cobra venom samples were examined. The contents of phosphodiesterase and phospholipase A of the venom samples were comparable: the phosphodiesterase activity varied from 52.4 to 89.3 unit/mg, whereas the phospholipase A activity varied from 115 to 239 pmole/min/mg.
First A s i a - Pacific Congress
Non-divergence theory of evolution: amino acid sequence comparison of proteroglyphous snake venom components. N. TAMIVA(Department of Chemistry, Tohoku University, Sendai, Japan). THERE ARE several different proposals on the systematics of proteroglyphous snakes, namely sea snakes, cobras, kraits, coral snakes, etc. The author compared the amino acid sequences of neurotoxins and phospholipases in these snake venoms. The classification varies according to the kinds of proteins considered, similarly to the morphological taxonomy. It is usually assumed that each species evolved by divergence from a common ancestor. It is even assumed that all the organisms on the earth evolved from a single ancestor. The use of the same 20 L-amino acids and the common codon system by all the organisms (the unity of life) is taken as the evidence for the existence of such an ancestor. The author proposes to abandon the assumption. The living organisms on the earth exchange information through various mechanisms, namely through sex, hybridization, infection and symbiosis. With all these mechanisms, the information shuffling among the organisms is so efficient that the unity of life is achieved. The situation is similar to the language unification in human society. Every organism on the earth is an expression of a bunch of information pieces in the stream of information. Every protein molecule or every part of a protein molecule has its own history which does not necessarily coincide with those of the others in the same organism or in the same molecule. The ultimate source of new information is mutation, but the new combination of the information is the essential factor for evolution. With efficient information shuffling mechanisms, evolution becomes inevitable rather than accidental.
Paralytic shellfish poisoning in Singapore. C. T. T. TAN and E. J. D. LEE (Department of Pathology, Outram Road, Singapore 0316). THIS PAPERreports the first outbreak of paralytic shellfish poisoning from green mussels in Singapore amongst a group of foreign workers, which resulted in two deaths. Green mussels left over from the meal were recovered and identified as Perna viridis and analysis of the meat by a standardised mouse bioassay technique showed that there was approximately 186 mouse units of toxin per gram of mussel meat. Epidemiological investigations showed the presence of considerable planktonic debris in the water where the toxic mussels had been collected, but the plankton could not be typed as they had disintegrated by the time the samples of water had been collected. Post-mortem examinations were conducted on the two fatal cases. No specific post-mortem changes were found. An attempt was made to extract and demonstrate the toxin from the stomach and intestinal contents recovered at the post-mortem examinations. Using the same standardised mouse bioassay technique it was possible to demonstrate a lethal effect for one of the intestinal contents and to produce abnormal behaviour in the mice for the other three specimens. The successful demonstration of the toxin in such biological specimens would be important in establishing the diagnosis of paralytic shellfish poisoning in situations where the clinical history of ingestion is weak or unavailable.
Thermal stability of snake venom enzymatic activities. NGET-HONG TAN and CHON-SENGTAN (Department of Biochemistry, University of Malaya, Kuala Lampur, Malaysia). The thermal stability of L-amino acid oxidase, hyaiuronidase, alkaline phosphomonoesterase, 5'-nucleotidase, protease, arginine ester hydrolase, phosphodiesterase, acetylcholinesterase, phospholipase A and coagulant enzyme in venoms from Trimeresuruspurpureomaculatus, Calloslasmarhodostoma, Naja naja atra, Naja naja
sputatrix, Enhydrina schistosa, Bitis arietans, Vipera russelli, Agkistrodon piscivorous, Crotalus atrox, Ophiophagus hannah, Echis carinatus, Bungarus fasciatus and Dendroaspis jamesoni were investigated. The venom enzymatic activities were stable at 4°C in physiological saline: most enzymes retained full activity after 46 days incubation. On the other hand, venom enzymatic activities were much less stable in 0.05 M Tris buffer (pH 8.5), particularly the L-amino acid oxidase and hyaluronidase activities. At 37°C in physiological saline the enzymes gradually lost activity. It is interesting to note, however, that even after 39 days incubation at 37°C some venom solutions still retained considerable amounts of enzymatic activities. The venom enzyme activities were very stable at room temperature if the venoms were stored as powder form. There was negligible loss in enzymatic activities after storage of the venoms at room temperature for 1 month.
Comparative enzymology of Asian cobra venoms. NGET-HONG TAN, A. ARMUGAM and CHON-SENG TAN (Department of Biochemistry, University of Malaya, Kuala Lumpur, Malaysia). The enzymatic activities of twelve Asian cobra venom samples were examined. The contents of phosphodiesterase and phospholipase A of the venom samples were comparable: the phosphodiesterase activity varied from 52.4 to 89.3 unit/mg, whereas the phospholipase A activity varied from 115 to 239 pmole/min/mg.