Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.1 (phosphodiesterase)
 18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

alpha- and beta-Fibrinogenases (EC 3.4.21.5) were purified from Trimeresurus mucrosquamatus venom by the technique of recycling chromatography. Both enzymes were single polypeptide chains and homogeneous as judged by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and ultracentrifugation. The sedimentation constants of alpha- and beta-fibrinogenases were 2.52 and 3.04 respectively. The molecular weight of alpha-fibrinogenase was 21 500--23 400, and that of beta-fibrinogenase was 25 000--26 000. The contents of proline, glycine and tryptophan were higher in beta-fibrinogenase than in alpha-fibrinogenase. The isoelectric points of alpha- and beta-fibrinogenases were pH 8.1 and 5.7 respectively. The optimal pH of alpha-fibrinogenase was about 7.4 and that of beta-fibrinogenase was around 8.5. The activity of alpha-fibrinogenase was completely destroyed after 30 min at 60 degrees C, pH 5.6, 7.4 and 9.0, while that of beta-fibrinogenase was not significantly affected by the same treatment. Both enzymes showed proteolytic activities toward fibrinogen and casein, but were devoid of phospholipase A, alkaline phosphomonoesterase and phosphodiesterase activities of the crude venom. The tosyl-L-arginine methylester esterase activity of beta-fibrinogenase was about 17 times that of the crude venom, while alpha-fibrinogenase was completely devoid of this activity. The fibrinogenolytic activity of alpha-fibrinogenase was markedly inhibited by EDTA and cysteine, while that of beta-fibrinogenase was inhibited markedly by phenylmethane sulfonylfluoride and slightly by tosyl-L-lysine chloromethylketone and cysteine.
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PMID:Physicochemical properties of alpha- and beta-fibrinogenases of Trimeresurus mucrosquamatus venom. 1 16

By means of DEAE-Sephadex A-50 Column chromatography, Trimeresurus gramineus venom was separated into twelve fractions. The fibrinogenolytic activities were distributed in Fractions 1 and 10. These enzymes were further purified by gel filtration and were homogeneous as judged by cellulose acetate membrane, sodium dodecyl sulfate polyacrylamide gel electrophoresis and ultracentrifugal analysis. Both of them were single peptide chains. The sedimentation constants of alpha- (Fraction 1) and beta-fibrinogenases (Fraction 10) were 2.20 and 3.60, respectively. The molecular weights of alpha- and beta-fibrinogenases were 23 500 and 25 000 respectively. The contents of proline and glycine were higher in beta-fibrinogenase than in alpha-fibrinogenase. The isoelectric points of alpha-fibrinogenase and beta-fibrinogenase were pH greater than 10 and 4.5, respectively. The optimal pH of alpha-fibrinogenase was approx. 7.4 and that of beta-fibrinogenase was approx. 9.0. The activity of alpha-fibrinogenase was completely destroyed after 30 min at 60 degrees C, pH 5.4, 7.4 and 9.0, while that of beta-fibrinogenase was much less affected by the same treatment. The specific fibrinogenolytic activity alpha-fibrinogenase was 31 mg fibrinogen/min per mg protein, while that of beta-fibrinogenase was 9 mg fibrinogen/min per mg protein. alpha-Fibrinogenase cleaved specifically the alpha(A) chain of monomeric fibrinogen without cleaving the beta(B) chain and gamma-chain. beta-fibrinogenase preferentially cleaved the beta(B) chain, and the alpha(A) chain was also partially cleaved by beta-fibrinogenase, if the incubation time was prolonged. Both enzymes showed proteolytic activities toward fibrinogen, fibrin and casein, but were devoid of phospholipase A, alkaline phosphomonoesterase and phosphodiesterase activities found in the crude venom. The tosyl-L-arginine methylester esterase activity of beta-fibrinogenase was about 14 times that of crude venom, while alpha-fibrinogenase was completely devoid of this activity. The fibrinogenolytic activity of alpha-fibrinogenase was markedly inhibited by EDTA and cysteine, while that of beta-fibrinogenase was inhibited markedly by phenylmethanesulfonylfluoride. alpha- and beta-fibrinogenases exert their fibrinogenolytic activity by a direct action on fibrinogen or fibrin without activation of plasminogen.
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PMID:Alpha and beta-fibrinogenases from Trimeresurus gramineus snake venom. 4 82

The Malayan pit viper (Calloselasma rhodostoma) is of major clinical significance both as a leading cause of snakebite and as the source of ancrod (Arvin). Although its venom has been extensively studied, the degree to which venom composition varies between individuals is poorly known. We individually analysed the venoms of over 100 C. rhodostoma using isoelectric focusing. In all populations, females produced an intense band that was absent from all males, and significant ontogenetic variation was detected. Principal components analysis of the banding profiles also revealed strong geographic variation, which was significantly congruent with variation in the biological activities of the venom (phosphodiesterase, alkalinephosphoesterase, L-amino acid oxidase, arginine ester hydrolase, 5'-nucleotidase, thrombin-like enzyme, haemorrhagic activity). Studies of captive-bred snakes indicate that the intraspecific variation in venom is genetically inherited rather than environmentally induced. The intraspecific variation in venom composition and biological activity could be of applied importance to snakebite therapy, both in correct diagnosis of the source of envenomation and in the development of a more effective antivenom. Greater attention should be given to the source of C. rhodostoma venom used in research to ensure reproducibility of results.
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PMID:Electrophoretic profiles and biological activities: intraspecific variation in the venom of the Malayan pit viper (Calloselasma rhodostoma) 1007 60