Which streptococcal extracellular product is known for its ability to break down DNA?

The correct answer is deoxyribonuclease B, which is an extracellular product associated with certain strains of Streptococcus bacteria. This enzyme has the specific capability of hydrolyzing DNA, a process that serves multiple purposes in the bacteria's interaction with the host and the immune response.

Deoxyribonuclease B aids in the breakdown of extracellular DNA, which can be particularly significant in the context of avoiding immune detection or aiding in the spread of infection. By degrading DNA, it can help to liquefy pus composed of immune cells and cellular debris, allowing the bacteria to disperse more easily through tissues. This enzymatic activity is particularly important in the pathogenicity of some streptococcal infections.

In contrast, hyaluronidase facilitates the breakdown of hyaluronic acid in connective tissues, allowing for increased tissue permeability. Streptokinase is an enzyme that activates plasminogen to plasmin, helping to dissolve blood clots. Streptolysin refers to a hemolysin produced by some streptococci that can lyse red blood cells and immune cells, but it does not have a direct role in DNA degradation.