• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.145-153
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• 1986

For the inactivation of venoms, the chemical methods are generally applied. In the chemical method many works have been carried out with the chemical reagents and immunological antiserums. However, all inhibitory effect of these chemicals acting on snake venomes may well be due not to the specific, but to the nonspecific inhibitory action. Therefore, it is necessary to separate venom into its compositional active proteins and develop specific inhibitor which acts on the each protein. Until now, there have not been any reports about the substance which acts on snake venom as a specific inhibitor. Recently in 1979, we had actually isolated a specific venom inhibitor(ISV) which has a strong inhibitory activity against the proteinase of snake venom of Colubridae. In our experiments described here, a strain of Aspergillus sp., isolated from soil, was able to produce a biological active substance. The partial crystallized substance had a strong inhibitory activity against hemorrhagic action of snake venom of Colubridae. For the inhibitory action of the sample on the lethality of venom, the substance prevented completely the lethal action of the hemorrhagic factor when they were treated with enough amount of the substance. The edema factor of whole venom of Agristrodon bromohoffi brevicaudus was completely inhibited, but those of HR-I and HR-II of Trimeresurus flavoviridis venom were inhibited about 50%, when they were treated with the substance of half amount of venom. On the other hand, from the result of subcutaneous hemorrhage in a rabbit, it was concluded that two kinds of antihemorrhagic substance might be produced by the strain used in this work.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.279-279
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• 1994

Fibrinolytic proteases, piscivorase I (PI) and piscivorase II (PII), were isolated from Agkistrodon piscivorus piscivorus (eastern cotonmouth moccasin) venom using gel filtration on Bio-Gel P100 and ion-exchange chromatography on CM-Sepharose. The molecular welghts of two proteases were approximately 23400 and 29000. Their isoelectric points 6.6 and 8.5, respectively. The partial amino acid sequences of PI were characterized by tryptic digestion. PI readily cleaves the A${\alpha}$-and B${\beta}$-chaln of fibronogen, but PII rapidly cleaves A${\alpha}$-chain and more slowly the B${\beta}$-chain, They were activated by Ca$\^$2+/, Mg$\^$2+/ and Ba$\^$2+/, but inhibited by Zn$\^$2+/, Cu$\^$2+/ and Mn$\^$2+/. Two enzymes were also inhibited by cysten, ${\beta}$-mercapto -ethanol, and by metal chelators such as EDTA and EGTA, but not by benzamidine, PMSF, soybean trypsin inhibitor and aprotinin. They did not act like thrombin, plasmin and kallikrein, using specific chromogenllc substrates. Two protease did not induce platelet aggregation. PI showed low hemorrhagic activity at dosage of 50 $\mu\textrm{g}$.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.239-240
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• 2001

Collagenases are generally defined as enzymes capable of degrading the polypeptide backbone of native collagen under conditions which do not denature the protein. Two types of proteases with collagenolytic activity have been reported and thought to play different physiological functions. Metallo-collagenases, firstly discovered in tadpole tissue explants are zinc-containing enzymes requiring calcium for optimum activity and stability, and These enzymes have been widely studied from various mammalian tissues as well as from bacteria, such as Bacillus cereus, Clostridium histolyticum, Achromobacter, Vibrio alginolyticus and Clostridium perfringens and snake venoms. (omitted)

• Microbiology and Biotechnology Letters
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• v.7 no.2
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• pp.75-89
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• 1979

One strain of Penicillium sp. (175-66-B), isolated from soil, was able to produce a substance that has a strong inibition activity against the Agkistrodon and Trimeresurus venoms. In this experiment, the chemical and biological properties of the sample were investigated. As an inhibitory substance, it was effective to the proteinase, hemorrhagic and lethal factors of Agkistrodon and Trimeresurus venoms, and also effective to several fractions of the proteinases and hemorrhagic factors of Agkistrodon halys blomhoffi venom. Moreover, in the addition of prednisotone, it was more effective for the cure of the mouse envenomated with the venom amount of two fold of MLD$_{100}$. This substance was very stable to the acid, alkali and heat. Its melting point was high enough to sublime at 222$^{\circ}C$ without any decomposition. This sample was easily dissolved only in hot water, but not in several organic solvents except for a little dissolution in elate. It did not have the chelating activity. It had very strong specificity to the snake venoms. but its activity was depressed by the addition of zinc or cupric salts. This sample had no acute toxicity to the mouse. Its chemical formula was $C_{16}$ $H_{12}$$N_2$ $O_{10}$ with the molecular weight of about 392. It has two epoxy groups and four carboxyl radicals, but amino, nitrite and nitrate radicals, unsaturated bonds and aromatic ring were not detected. Theuchemical configuration of this sample was suggested to be;

• Journal of Animal Science and Technology
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• v.59 no.9
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• pp.20.1-20.9
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• 2017

Background: Ribonuclease (RNase) is one of the few toxic proteins that are present constantly in snake venoms of all types. However, to date this RNase is still poorly studied in comparison not only with other toxic proteins of snake venom, but also with the enzymes of RNase group. The objective of this paper was to investigate some properties of RNase from venom of Vietnam cobra Naja atra. Methods: Kinetic methods and gel filtration chromatography were used to investigate RNase from venom of Vietnam cobra. Results: RNase from venom of Vietnam cobra Naja atra has some characteristic properties. This RNase is a thermostable enzyme and has high conformational stability. This is the only acidic enzyme of the RNase A superfamily exhibiting a high catalytic activity in the pH range of 1-4, with $pH_{opt}=2.58{\pm}0.35$. Its activity is considerably reduced with increasing ionic strength of reaction mixture. Venom proteins are separated by gel filtration into four peaks with ribonucleolytic activity, which is abnormally distributed among the isoforms: only a small part of the RNase activity is present in fractions of proteins with molecular weights of 12-15 kDa and more than 30 kDa, but most of the enzyme activity is detected in fractions of polypeptides, having molecular weights of less than 9 kDa, that is unexpected. Conclusions: RNase from the venom of Vietnam cobra is a unique member of RNase A superfamily according to its acidic optimum pH ($pH_{opt}=2.58{\pm}0.35$) and extremely low molecular weights of its major isoforms (approximately 8.95 kDa for RNase III and 5.93 kDa for RNase IV).

• Toxicological Research
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• v.14 no.3
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• pp.435-441
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• 1998

Alginase$Alginase^{ⓡ}$ (Arginine esterase) is one of the snake venoms which is mainly consisted of arginine esterase and acts as a thrombus -forming inhibitor/thrombus-lysin. These present studies were performed to investigate of the acute and subacute toxicity of the Alginase$Alginase^{ⓡ}$ in rats. In acute toxicity study, rats were single administered intravenously with dosages of 0.001, 0.01. 0.1, 1 and 10U/kg B.W. and examined the number of death, clinical sign, body weight and pathological change for 7days after administration of Alginase$Alginase^{ⓡ}$. At maximum dose level (10U/kg B.W.), Alginase$Alginase^{ⓡ}$ induced symptoms of shock with cyanosis and dyspnea. But these symptoms dissappeared after 30~50 minutes and we could not find any other toxic effect in rats. Therefore, $LD_{50}$ Value of Alginase was over 10U/kg B.W. in rats. In four-week intravenous toxicity study of Alginase$Alginase^{ⓡ}$, rats were administered intravenously seven days per week for 28 days, with dosages of 0, 0.0125, 0.125 and 1.25U/kg B.W./day, respectively. Alginase$Alginase^{ⓡ}$ did not caused any death and showed any clinical signs in rats. No significant Alginase$Alginase^{ⓡ}$ -related changes were found in feed uptake, water consumption, hematology, serum biochemistry, urinalysis, ocular examination, organ weight and histopathological examination. From the results, Alginase$Alginase^{ⓡ}$ seems not to have any toxic effect in rats when it were given daily intravenous injections below the dosage 1.25U/kg B.W./day for four weeks.