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V N Orekhovich

Publications and source records attributed to V N Orekhovich.

At least 73 records · Page 4Linked to original sources

[Protease from bovine spleen with kininogenase activity].

A protease with kininogenase activity at pH 7.5 was isolated from bovine spleen extract by gel filtration and ion exchange chromatography. The protease was found in the fraction with molecular weight lower than 25.000 and was separated from the other neutral SH-dependent protease by chromatography on KM-cellulose. The kininogenase activity was inhibited by DFP and trasylol; soybean trypsin inhibitor had no effect. The protease did not split N-benzoyl-L-arginine ethyl ester and N-benzoyl-D, L-arginine p-nitroanilide.

Animals↗

[Isolation and properties of carboxycathepsin (peptidyl-dipeptidase) from bovine lung tissue].

2200-fold purified homogenous preparation of carboxycathepsin (peptidyl-dipeptidase) is isolated from bovine lung. The enzyme isolated converts angiotensine I into angiotensine II and distroys bradikinin. It is active in neutral medium, is activated by chloride ion and is inhibited by EDTA and Middle Asian snakes venom. The molecular weight of the enzyme is 180 000-190 000 as estimated by means of polyacrylamide gel electrophoresis, its isoelectric point is 4.48-4.53. The comparison of properties and specificity of carboxycathepsin from bovine lung and kidney draws to the conclusion that both enzymes are identical.

Angiotensin-Converting Enzyme Inhibitors↗

Some properties of cathepsins chemically fixed to carriers.

An insoluble preparation of rat liver cathepsin D was obtained by coupling the enzyme to Enzacryl Polyacetal (EPA-cathepsin) and to CNBr-activated Sepharose 4B. EPA-cathepsin was active toward the synthetic hexapeptides (Gly-Phe-Leu)2 and did not split hemoglobin. The optimum pH of splitting was displaced upward by 1.5 units to pH 5.0. The enzyme exhibited maximum activity at 60 degrees C. No appreciable loss of activity was seen on storage of the enzyme for 4 months or after repeated use of the preparations. Coupling of rat liver cathepsin D to activated Sepharose gave preparations active towards both protein and synthetic substrates. The preparations were totally inactive in acid media and exhibited maximum activity at pH 7.0, that is, under physiological conditions. Optimum temperature was 65 degrees. The specific activity of the preparations (pH 7.0, 65 degrees) was 60-110 percent that of the free enzyme in acid media. Proteolytic activity of the Sepharose-coupled cathepsin D was not inhibited by pepstatin, whereas that of the free enzyme was fully inhibited by this reagent. A sarcoma cathepsin, similar in some of its properties to the rat liver enzyme, was also coupled to CNBr-activated Sepharose 4B. The preparation split protein substrates at pH 7.0 and possessed enhanced thermostability. The enzymes fixed on Sepharose showed increased stability.

Acetals↗