Originally Posted by
Puppycow
I unsubscribed from his channel after that video, but the YouTube algorithm keeps recommending his videos to me. Apparently his
latest one is a diatribe because he got fact-checked by Facebook.
I could not make it all the way through this video, but I did skip around a bit. Two compounds that are protease inhibitors may differ in their details. There are reversible, reversible covalent, and irreversible (typically covalent) protease inhibitors. That may be something of a quibble, but there is also the question of differing affinities. In addition even high affinity is no guarantee that an inhibitor will be a successful drug.
Regarding how we know that a compound binds to a particular enzyme
in vitro, there are computational methods (including docking), determination of the structure (usually by X-ray crystallography), and kinetic methods that examine the rate at which the enzyme converts its substrate into products.