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E Zlotkin 《Experientia》1973,29(12):1453-1466
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Conclusion I have discussed in this article only the most active toxins, with the result that many interesting substances have been omitted, e.g. the toxins from bee and wasp venoms (apamin, melittin, etc.), of many amphibians (bufotoxins, etc.), ciguatoxins, and many more. Poisons are found in every phylum except birds. Shrews exemplify venomous mammals. One gets a good illustration of the number of poisonous animals by studying the monumental and impressive work byHalstead 106 which consequently excludes terrestrial animals. An interesting fact in this connection is that there are about 20,000 species of spiders, most of which are poisonous.A toxin ranking list has to be included in an article of this kind. The list is, of course, far from complete. Data on molecular weights, mouse lethal doses, etc. are lacking for many potent toxins, such as the dysentery toxin, a neurotoxin with a toxicity comparable to that of the botulinus toxins107, the toxins from the jelly fishChironex fleckeri 106.A comparison on molar basis gives a better notion of the toxicities. Curare has about 1/30 of the toxicity of the curarimimetic snake venom neurotoxins, clearly indicating that curare has a much lower affinity for the acetylcholine receptor.Toxic organisms have developed during millions of years more and more refined toxins, and this evolution has probably brought into existence toxins against every physiological function. Neurochemistry is to a great extent unexplored. Progress in this field will in the nearest future depend on specific toxins from various natural sources. Toxins from spiders, scorpions, snakes, frogs, and fishes are therefore not mere curiosities but valuable tools for research on the molecular mechanisms of neural function and synaptic transmission.  相似文献   

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Fibrinolytic proteases in snake venoms   总被引:1,自引:0,他引:1  
F Kornalik  Z Styblová 《Experientia》1967,23(12):999-1000
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Zusammenfassung Fibrinolysine zweier Schlangengifte haben — im Gegensatz zu Plasmin und Trypsin — keinen Plasminogen-aktivierenden Effekt, noch sind sie durch Proteasen-Inhibitoren gehemmt. Sowohl in vivo wie auch in vitro sind sie durch Plasmaproteine inaktiviert, was jedoch nicht auf 1 und 2-Antiplasmine zurückzuführen ist. Die Spaltprodukte der Toxin-Fibrinogenolyse besitzen einen hohen Gehalt an Antithrombin VI.  相似文献   

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Résumé Les phospholipases A des venins du serpentVipera palestinae et duNaja naja ne clivent pas des phospholipides de leucocytes intacts, sauf en présence d'un facteur lytique se trouvant dans le venin deNaja naja. L'activité des phospholipases des deux venins sur les leucocytes endommagés n'est pas la même.  相似文献   

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Zusammenfassung Im Schlangengift vonBothrops befindet sich ein Peptid, welches als Phospholipase-Hemmer beschrieben wird.  相似文献   

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Résumé Pour déterminer le caractère des exo-peptidases dans le venin des serpents on a employé comme substrat dul-leucyl--napthylamide. Des venins de 49 espèces et sous-espèces des 4 familles de serpents venimeux ont été étudiés. La capacité d'hydroliser ce substrat a été rencontrée assez souvent dans les venins des serpents venimeux quelles que joient leurs origines géographiques ou leurs différences génétiques.

This work was supported by Public Health Service Grant No. 1 RO1 GM14174 and Office of Naval Research Contract No. N00014-67-A-0220-0001.  相似文献   

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Gram-positive and -negative bacteria are dangerous pathogens that may cause human infection diseases, especially due to the increasingly high prevalence of antibiotic resistance, which is becoming one of the most alarming clinical problems. In the search for novel antimicrobial compounds, snake venoms represent a rich source for such compounds, which are produced by specialized glands in the snake’s jawbone. Several venom compounds have been used for antimicrobial effects. Among them are phospholipases A2, which hydrolyze phospholipids and could act on bacterial cell surfaces. Moreover, metalloproteinases and l-amino acid oxidases, which represent important enzyme classes with antimicrobial properties, are investigated in this study. Finally, antimicrobial peptides from multiple classes are also found in snake venoms and will be mentioned. All these molecules have demonstrated an interesting alternative for controlling microorganisms that are resistant to conventional antibiotics, contributing in medicine due to their differential mechanisms of action and versatility. In this review, snake venom antimicrobial compounds will be focused on, including their enormous biotechnological applications for drug development.  相似文献   

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Zusammenfassung Die Strukturaufklärung von zwei neuen tryptophanhaltigen Peptiden im Schlangengift vonAgkistrodon halys blomhoffii ergeben:l-Pyroglutamyl-l-Glutaminyl-l-Tryptophan undl-Pyroglutamyl-l-Asparaginyl-l-Tryptophan. Diese Peptide sind in Schlangengiften der Viperidae- und Crotalidae-Arten verbreitet.

Supported in part by a grant from the Ministry of Education (Japan).  相似文献   

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Zusammenfassung Die Anwesenheit von Dopamin und Noradrenalin im Bienen- und Wespengift wurde durch Fluoreszenzmikroskopie, Dünnschichtchromatographie und Spectrophotofluorimetrie nachgewiesen. Der Dopamin-Gehalt eines Stiches genügt, um die Herztätigkeit eines Insekts zu beschleunigen, was auch die Verteilung der giftigen Bestandteile zu den Wirkungsstellen beeinflussen kann.

This work was supported by O.N.R. Grant No. AR-305-807 to Dr.B. I. Shapiro. The technical assistance of MissE. King and Mrs.M. Goldstone is acknowledged, as is the advice and encouragement drawn fromB. I. Shapiro andI. M. Cooke.  相似文献   

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M D Owen 《Experientia》1971,27(5):544-545
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G Ohloff 《Experientia》1986,42(3):271-279
The present state of the molecular basis of olfaction is shown. With the aid of various examples the regioselectivity of odor sensation is proven. The main part of the experimentation concerns the stereocontrolled process of odor release.  相似文献   

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Summary The present state of the molecular basis of olfaction is shown. With the aid of various examples the regioselectivity of odor sensation is proven. The main part of the experimentation concerns the stereocontrolled process of odor release.  相似文献   

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回顾了20世纪化学学科的发展,明确提出化学在推动人类进步和科技发展中起了核心科学的作用,论述了未来化不科发展趋势才研究模式,探讨了相关学科中的基本化学问题。  相似文献   

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