Streptolysins

Streptolysins are a group of cytotoxic proteins produced by certain species of streptococci. The name "streptolysins" comes from the prefix "strepto-", indicating an association with streptococci, and the word "lysis", meaning decomposition or disintegration.

Streptolysins are pore-forming toxins - they interact with cell membranes and form pores in them, which leads to cell death. The main types of streptolysins are streptolysin O and streptolysin S. They differ in structure, mechanism of action and cellular targets.

Streptolysins play an important role in the pathogenicity of streptococci, being the main factor in the cytotoxicity of these bacteria. They are involved in tissue damage during streptococcal infections, such as scarlet fever, erysipelas, etc. The study of streptolysins is important for understanding the mechanisms of virulence of streptococci and developing methods to combat the diseases they cause.

Streptolysins are a group of exotoxin proteins produced by certain species of streptococci. They are pore-forming toxins and are capable of destroying cell membranes, causing cell lysis.

Streptolysins are divided into several types depending on their properties:

1. Streptolysin O - the most studied streptolysin, is unstable in the presence of oxygen, but is activated by calcium ions. Destroys red blood cells, leukocytes, platelets, endothelial and epithelial cells.

2. Streptolysin S is resistant to oxygen and does not require calcium ions for activation. Lyses red blood cells, leukocytes and platelets.

3. Streptolysin U (hemolysin) - causes hemolysis of red blood cells.

Streptolysins play an important role in the pathogenesis of streptococcal infections, facilitating the penetration of bacteria into tissues and the development of inflammatory processes. They can be used as markers in the identification of streptococcus pyogenes and some other species of streptococci. Streptolysins are also considered as potential therapeutic agents for the destruction of tumor cells.