About the HIV-1 protease, from Wikipedia:
HIV-1 protease (HIV PR) is an aspartic protease that is essential for the life-cycle of HIV, the retrovirus that causes AIDS. HIV PR cleaves newly synthesized polyproteins at the appropriate places to create the mature protein components of an infectious HIV virion. Without effective HIV PR, HIV virions remain uninfectious. Thus, mutation of HIV PR’s active site or inhibition of its activity disrupts HIV’s ability to replicate and infect additional cells, making HIV PR inhibition the subject of much pharmaceutical research.
The animation below shows the mechanism of action of the protease inhibitors (PIs), the first scene is the same as in the previous animation.
Antiretrovirals from the protease inhibitors group include: Saquinavir (Fortovase, Invirase), Ritonavir (Norvir), Indinavir (Crixivan), Nelfinavir (Viracept), Amprenavir (Agenerase), Lopinavir (Kaletra), Atazanavir (Reyataz), Fosamprenavir (Lexiva), Tipranavir (Aptivus), Darunavir (Prezista).
The author of these animations is Gary E. Kaiser, Ph.D., Microbiology Professor at The Community College of Baltimore County, Catonsville Campus.