Collagenase and hyaluronidase degrade collagen and hyaluronic acid, respectively, thereby allowing the bacteria to spread through subcutaneous tissue (Streptococci, Staphylococci, Clostridium ).
Immunoglobulin A protease degrades IgA, allowing the organism to adhere to mucous membranes, and is produced chiefly by N. gonorrhoeae, Haemophilus influenzae, and S. pneumoniae.