title: [Proteolysis of horse blood serum proteins at various stages of antitoxic sera production by the Diaferm-3 method].
abstract: When preparing antitoxic sera by the method "Diaferm-3", it was found that proteolysis of the horse blood serum occurs not only at the fermentation step (pepsin treatment at the enzyme-substrate ratio of 1/10, t 20-23 degrees for an hour at pH 3.3 and for the next hour at pH 4.2), but also at the heat treatment step (45 min at pH 4.3, t 56-58 degrees in the presence of ammonium sulfate at a concentration of 140-145 g/l). At the fermentation step immunoglobulins do not split completely into F(ab')2 fragments, 40% of the antitoxic activity being lost at this step. Some ballast proteins--albumin, fibrinogen, etc.--quickly split up into peptides, while other proteins undergo only limited proteolysis. Structural destabilization of serum proteins during thermodenaturing is favorable for the pepsin action and provides for a complete conversion of immunoglobulins to F(ab')2 and Fab' fragments. At this step about 15% of the antitoxic activity is additionally lost. Thus, proteolysis at the thermodenaturation step is an essential part of the "Diaferm-3" process.
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D006736:Horses / Q000276:immunology; D006863:Hydrogen-Ion Concentration; D007106:Immune Sera / Q000302:isolation & purification*; D007074:Immunoglobulin G / Q000032:analysis / Q000378:metabolism; D008722:Methods; D010434:Pepsin A / Q000378:metabolism*; D013696:Temperature; D013745:Tetanus Toxoid / Q000302:isolation & purification; D013997:Time Factors
chemical_list: D001798:Blood Proteins; D007106:Immune Sera; D007074:Immunoglobulin G; D013745:Tetanus Toxoid; D010434:Pepsin A
vernacular_title: O proteolize belkov syvorotki krovi loshadi na razlichnykh stadiiakh polucheniia antitoksicheskikh syvorotok po metodu "Diaferm-3".