Streptococcus, lysis

Streptokinase is a 48 kDa extracellular bacterial protein produced by several strains of Streptococcus haemolyticus group C. Its ability to induce lysis of blood clots was first demonstrated in 1933. Early therapeutic preparations administered to patients often caused immunological and other complications, usually prompted by impurities present in these products. Chromatographic purification (particularly using gel filtration and ion-exchange columns) overcame many of these initial difficulties. Modern chromatographically pure streptokinase preparations are usually supplied in freeze-dried form. These preparations (still obtained by non-recombinant means) often contain albumin as an excipient. The albumin prevents flocculation of the active ingredient upon its reconstitution. 

Pneumococcal vaccine is a bacterial vaccine that induces antibodies against 23 capsular types of Streptococcus pneumoniae. The type-specific antibody facilitates bacterial destruction by complement-mediated lysis. It is indicated in protection against pneumococcal pneumonia, pneumococcal bacteremia, and other pneumococcal infections. This bacterial vaccine is used for pneumococcal immunization. 

Feirtag, J. M.. and McKay, L. L. (1987). Thermoinducable lysis of temperature sensitive Streptococcus cremoris strains. J. Dairy Sci. 70, 1779-1784. 

Enterotoxins. Toxic proteins formed by bacteria with molecular masses in the range from 27000 to 30000 which are usually excreted into the medium ( exotoxins). E. can be taken up with contaminated food or be formed by the bacteria colonizing the intestinal walls. Finally, the bacteria can penetrate the intestinal walls and then start to excrete the E. Some E. are thermally very stable and survive when food is boiled. E. from Salmonella and Staphylococcus species are the most frequent causes of food poisoning. Shortly after uptake, the symptoms of nausea, vomiting, diarrhea, and circulatory complaints occur. Deaths are rare and occur only when the subject is already in a weakened state. The sites of attack by E. vary, e.g., at intestinal epithelial cells or in the vegetative nervous system. For the production of antitoxins, E. are obtained by lysis of bacterial cells or from cell-free culture filtrates. E. have been detected, e. g., in the following bacterial species Bacillus cereus, Clostridium perfringens, Escherichia coli. Vibrio cholerae. Staphylococcus aureus, and Streptococcus faecalis. 

Deutsch, S.M., Ferain, T., Delcour, J., and Lortal, S. (2002) Lysis of lysogenic strains of Lactobacillus helveticus in Swiss cheeses and first evidence of concomitant Streptococcus thermophilus lysis. Int Dairy J 12, 591-600. 

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