Comparative biochemistry and physiology. B. Comparative biochemistry, 1986
ABSTRACT Nerve growth factor from Vipera berus berus venom was purified by gel filtration on Seph... more ABSTRACT Nerve growth factor from Vipera berus berus venom was purified by gel filtration on Sephadex G-100 (superfine), ion-exchange-chromatography on DEAE-Sephadex A-50 and chromatofocusing on PBE 118. The Vipera berus berus venom NGF consists of multiple molecular forms with pls in the interval 9.1-9.7. All isoforms have identical mol. wts approximately 35,000 +/- 3000 (in gel filtration) and 17,000 +/- 2000, 15,000 +/- 2000 (by SDS electrophoresis with beta-mercaptethanol). V. berus berus venom NGF reacted with monoclonal antibodies against Viper lebetina NGF and caused differentiation of pheochromocytoma PC12 cells.
Crystals of nerve growth factor purified from Vipera lebetina venom have been grown by the vapour... more Crystals of nerve growth factor purified from Vipera lebetina venom have been grown by the vapour diffusion method from concentrated solutions of ammonium sulphate. The crystals, which have the form of trigonal, elongated prisms (0.3×0.3×1.0 mm), diffract X-rays to at least 3.2 A resolution and belong to the R32 space group (rhombohedral packing). The hexagonal unit cell parameters have been determined from precession and oscillation photographs as follows: a = b = 301.1 A, c = 247.5 A, α = β =90°, γ=120°, V = 1.08×106A3. The crystalline protein retains its activity when tested in vitro.
Pathophysiology of Haemostasis and Thrombosis, 2001
Our studies of the venom from the Levantine viper Vipera lebetina have demonstrated the existence... more Our studies of the venom from the Levantine viper Vipera lebetina have demonstrated the existence of both coagulants and anticoagulants in the same venom. We showed that V. lebetina venom contains: (1) proteases that degrade fibrinogen, but not fibrin; (2) fibrinolytic enzyme (lebetase); (3) factor X activator (VLFXA); (4) factor V activator (VLFVA). Fibrinolytic enzyme and VLFXA are metalloproteases; the other studied enzymes are serine proteases. α-Fibrinogenase has no homolog among known serine proteases. β-Fibrinogenase is a typical thermostable arginine esterase that hydrolyzes esters and amides of arginine and attacks the β-chain of fibrinogen. Lebetase is a direct-acting fibrinolytic zinc metalloendopeptidase related in amino acid sequence to reprolysins. We used the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technique for the recovery and identification of peptides released by protease hydrolysis and for the detection of human factor X cleav...
Pathophysiology of Haemostasis and Thrombosis, 2005
Snake venoms contain four classes of metalloproteases that all have a typical zinc-chelating sequ... more Snake venoms contain four classes of metalloproteases that all have a typical zinc-chelating sequence (HEXXHGXXH). N-terminal sequences and internal sequences of different purified metalloproteases were determined using Edman sequencing and LC MS/MS technique. Oligonucleotideswere designed and used as primers for cDNA cloning from Vipera lebetina venom gland cDNA library. We found that isoforms of fibrinolytic enzyme lebetase Le-4 and Le-3 are synthesized in different way: Le-4 is synthesized as P-I type metalloprotease, Le-3 is synthesized with disintegrin-like domain as P-II type protease and processed post-translationally. An endothelial cell apoptosis-inducing heterodimeric glycosylated metalloprotease, V. lebetina apoptosis-inducing protease (VLAIP), belongs to P-III type containing metalloprotease, disintegrin-like and cysteine-rich domains. All these enzymes hydrolyze the Aα-chain and more slowly the Bβ-chain of fibrinogen. Treatment of HUVEC cells with VLAIP induces changes ...
Chapter 26 Activation of Factor X by Snake Venom Proteases Jüri Siigur and Ene Siigur Abstract Hu... more Chapter 26 Activation of Factor X by Snake Venom Proteases Jüri Siigur and Ene Siigur Abstract Human coagulation factor X is a serine protease zymogen, which circu-lates in blood as a two-chain molecule. A variety of factor X activators have been detected in snake venoms. ...
Comparative biochemistry and physiology. B. Comparative biochemistry, 1986
ABSTRACT Nerve growth factor from Vipera berus berus venom was purified by gel filtration on Seph... more ABSTRACT Nerve growth factor from Vipera berus berus venom was purified by gel filtration on Sephadex G-100 (superfine), ion-exchange-chromatography on DEAE-Sephadex A-50 and chromatofocusing on PBE 118. The Vipera berus berus venom NGF consists of multiple molecular forms with pls in the interval 9.1-9.7. All isoforms have identical mol. wts approximately 35,000 +/- 3000 (in gel filtration) and 17,000 +/- 2000, 15,000 +/- 2000 (by SDS electrophoresis with beta-mercaptethanol). V. berus berus venom NGF reacted with monoclonal antibodies against Viper lebetina NGF and caused differentiation of pheochromocytoma PC12 cells.
Crystals of nerve growth factor purified from Vipera lebetina venom have been grown by the vapour... more Crystals of nerve growth factor purified from Vipera lebetina venom have been grown by the vapour diffusion method from concentrated solutions of ammonium sulphate. The crystals, which have the form of trigonal, elongated prisms (0.3×0.3×1.0 mm), diffract X-rays to at least 3.2 A resolution and belong to the R32 space group (rhombohedral packing). The hexagonal unit cell parameters have been determined from precession and oscillation photographs as follows: a = b = 301.1 A, c = 247.5 A, α = β =90°, γ=120°, V = 1.08×106A3. The crystalline protein retains its activity when tested in vitro.
Pathophysiology of Haemostasis and Thrombosis, 2001
Our studies of the venom from the Levantine viper Vipera lebetina have demonstrated the existence... more Our studies of the venom from the Levantine viper Vipera lebetina have demonstrated the existence of both coagulants and anticoagulants in the same venom. We showed that V. lebetina venom contains: (1) proteases that degrade fibrinogen, but not fibrin; (2) fibrinolytic enzyme (lebetase); (3) factor X activator (VLFXA); (4) factor V activator (VLFVA). Fibrinolytic enzyme and VLFXA are metalloproteases; the other studied enzymes are serine proteases. α-Fibrinogenase has no homolog among known serine proteases. β-Fibrinogenase is a typical thermostable arginine esterase that hydrolyzes esters and amides of arginine and attacks the β-chain of fibrinogen. Lebetase is a direct-acting fibrinolytic zinc metalloendopeptidase related in amino acid sequence to reprolysins. We used the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technique for the recovery and identification of peptides released by protease hydrolysis and for the detection of human factor X cleav...
Pathophysiology of Haemostasis and Thrombosis, 2005
Snake venoms contain four classes of metalloproteases that all have a typical zinc-chelating sequ... more Snake venoms contain four classes of metalloproteases that all have a typical zinc-chelating sequence (HEXXHGXXH). N-terminal sequences and internal sequences of different purified metalloproteases were determined using Edman sequencing and LC MS/MS technique. Oligonucleotideswere designed and used as primers for cDNA cloning from Vipera lebetina venom gland cDNA library. We found that isoforms of fibrinolytic enzyme lebetase Le-4 and Le-3 are synthesized in different way: Le-4 is synthesized as P-I type metalloprotease, Le-3 is synthesized with disintegrin-like domain as P-II type protease and processed post-translationally. An endothelial cell apoptosis-inducing heterodimeric glycosylated metalloprotease, V. lebetina apoptosis-inducing protease (VLAIP), belongs to P-III type containing metalloprotease, disintegrin-like and cysteine-rich domains. All these enzymes hydrolyze the Aα-chain and more slowly the Bβ-chain of fibrinogen. Treatment of HUVEC cells with VLAIP induces changes ...
Chapter 26 Activation of Factor X by Snake Venom Proteases Jüri Siigur and Ene Siigur Abstract Hu... more Chapter 26 Activation of Factor X by Snake Venom Proteases Jüri Siigur and Ene Siigur Abstract Human coagulation factor X is a serine protease zymogen, which circu-lates in blood as a two-chain molecule. A variety of factor X activators have been detected in snake venoms. ...
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