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T A Otroshko

Publications and source records attributed to T A Otroshko.

6 recordsLinked to original sources
PubMedDate not supplied

[Exoprotease properties of Bacillus subtilis var. amyloliquefaciens capable of coagulating blood plasma].

The properties of the homogeneous exoprotease preparation from Bacillus subtilis varamyloliquefaciens 759 possessing the coagulase activity were studied. The enzyme is an alkaline protease, has the isopoint at pH 7.8, and not only clots blood plasmo but also hydrolyses such protein substrates as casein, hemoglobin, fibrinogen and fibrin. The enzyme is relatively stable at pH 6.0--9.0. Bivalent metal ions have virtually no effect on the enzyme activity though some of them stabilize it. The inhibitors PCMB and EDTA do not affect the activity of the enzyme whereas diisopropylfluorophosphate completely inactivates it. Fibrinogen is clotted by the enzyme only in the presence of blood plasma factors.

Bacillus subtilis↗
PubMedDate not supplied

[Effect of different carbon, nitrogen and phosphorus sources on the biosynthesis of proteases with coagulase activity by Bacillus subtilis var, amyloliquefaciens].

Proteolytic enzymes with coagulase activity were found in the cultural broth of Bacillus subtilis var. amyloliquefaciens 759 grown on chemically defined and natural media. The effect of various sources of carbon, nitrogen and phosphorus on biosynthesis of proteases with coagulase activity was studied; mineral and organic nitrogen sources were equally favourable for the growth and protease biosynthesis. The best sources of carbon for biosynthesis of the enzymes were glucose, sucrose, maltose, fructose, and sorbitol. Potassium salts of ortho-phosphoric acid were assimilated as a source of phosphorus.

Bacillus subtilis↗
PubMedDate not supplied

[Proteolytic enzymes produced by Aspergillus ochraceus in relation to their plasma coagulating and fibrinolytic activities].

The paper describes some properties of coagulases and fibrinolytic enzymes isolated from a proteolytic complex produced by Aspergillus ochraceus HP-19 during submerged cultivation on a synthetic medium. Proteolytic enzymes with the plasmocoagulating activity hydrolyzed casein at the maximum rate at 45 degrees C and pH 8.0--10.0. The coagulases were stable at pH 5.0--7.0 and were rather resistant to low pH values. The enzymes were entirely inactivated at 55 degrees C within 20--30 min. The activity of the coagulases was inhibited with the ions of Cu, Co, Ag, Pb, Mn, Zn and Hg (1.10(-3) M) by 100, 91, 85, 50, 50, 38 and 25%, respectively. The coagulases were entirely inhibited with EDTA whereas PCMB and PMSF inhibited their activity only to a small extent. The mechanism for blood clotting with the coagulases of Aspergillus ochraceus HP-19 is presumed to consist in the activation of protrombin via its limited specific proteolysis. The fibrinolytic enzymes of Aspergillus ochraceus HP-19 had the optimal pH 8.5 for casein, were stable at pH 6.0, and entirely inactivated at 55 degrees C within 5 min. In contrast to coagulases, they were resistant to the action of heavy metal ions. The enzymes were stabilized by the ions of Ca. The activity of the fibrinolytic enzymes of Aspergillus ochraceus HP-19 was completely inhibited with PMSF. Therefore, they belong to the class of serine proteases.

Aspergillus↗
PubMedDate not supplied

[Proteolytic system of Aspergillus ochraceus studied in relation to its plasma-coagulating and fibrinolytic activities].

The culture of Aspergillus ochraceus HP-19 accumulates two types of proteolytic enzymes in the cultural broth. One group of proteases coagulates blood while the other has the fibrinolytic activity. The enzymes can be separated by gel filtration on Sephadex G-100. The first group of enzymes consists of several proteases with the coagulase activity and an inert protein.

Aspergillus↗