Pfizer's drug "Paxlovid" is a 3CL protease inhibitor, a type of antiviral medication that has been used against HIV, the virus that causes AIDS.

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Co-evolution of multipartite interactions between an extended tmRNA tag and a robust Lon protease in Mycoplasma

https://pubmed.ncbi.nlm.nih.gov/19912542/

Proteases as Secreted Exoproteins in Mycoplasmas from Ruminant Lungs and Their Impact on Surface-Exposed Proteins

https://pubmed.ncbi.nlm.nih.gov/31540994/