Streptococci hemolytic, enzymes

Streptokinase. Streptokinase is a single-chain protein containing 415 amino acids, mol wt of 45,000 to 50,000 (261,284—286). It is produced by P-hemolytic streptococci and is not an enzyme per se. Only after streptokinase combines with plasminogen on a 1 1 basis to form a... 

Co-enzyme obtained from cultures of various strains of Streptococcus haemolyticus and capable of changing plasminogen into plasmin (complex enzyme mixture of streptokinase, streptodornase and streptolysin 0"). From fermentation liquors of hemolytic streptococci species Streptococcus haemolyticus), e. g. H 46 A. 

Streptokinase. Streptokinase (Kabikinasc. Streptase) is a catabolic 47.000-Da protein secreted by group C fi-hemolytic streptococci. It is a protein with no intrinsic enzymatic activity. Streptokinase activates plasminogen to plasmin. a proteolytic enzyme that hydrolyzes fibrin and... 

Varidase = 10 000 lU streptokinase and 2500 lU streptodornase. Streptokinase is a protein, an enzyme produced by beta-hemolytic streptococci. It has indirect fibrinolytic properties by binding with plasminogen. It is a fibrin non-specific thrombolytic. 

In 1936 Meyer and coworkers [1] described an enzyme in autolysates of certain pneumococci that hydrolyzed hyaluronan. In 1940 Chain and Duthie [1] showed that the testicular extract described by Duran-Reynals also hydrolyzed hyaluronan. Similar activity was shown in virulent and avirulent strains of type I pneumococci, in group C hemolytic streptococci, in the skin of rabbits, in the venom of many poisonous snakes, and in bee venom. 

Streptokinase (SK), in spite of its name (-ase suffix), is a nonenzyme protein (mol. wt. 47,000). It is a catabolic product of group C 3-hemolytic streptococci. Unlike the real enzymes to be considered, it activates the fibrinolytic system indirectly. More recent research has shown that necessary steps require a prior formation of a 1 1 complex with plasminogen. This alters its conformation, thereby exposing an active site in the modified proenzyme. It is this modified complex that becomes the actual PA. SK is still a widely used thrombolytic agent, primarily because it is the least costly, is easy to obtain and had been in use for years before other PAs became available. 

Streptokinase, an extracellular protein (415 aa, Mr 47 kDa) produced by various strains of /3-hemolytic streptococci. Streptokinase is not generally considered to be a proteolytic enzyme, but is one of the most potent exogenous activators of human plasminogen. Complexes of streptokinase with human plasminogen can hydrolytically activate other plasminogen molecules to plasmin which then dissolves blood clots alone [L. A. Schick, F. J. Castellino, Biochem. Biophys. Res. Commun. 1974, 57, 47 K. W. Jackson, J. Tang, Biochemistry 1982, 21, 6620]. 

An extracellular DPNase from hemolytic streptococci has been quite extenfflvely purified the enzyme appears to be associated with the ability of the streptococci to kill leucocytes 172,173). 

The production of a papainlike enzyme by certain strains of group A hemolytic streptococci and its possible relation to virulence (Elliott, 38) has already been discussed. A great many other strains of pathogenic bacteria produce proteolytic enzymes of the papain or trypsin type. 

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