Yoel Romero looks like he is next for Michael Bisping, while Luke Rockhold and Ronaldo Souza are still waiting in the wings; the Ultimate Fighting Championship does not need another 185-pound power player right now....
In biology, the active site is the region of an enzyme where substrate molecules bind and undergo a chemical reaction. The active site consists of residues that form temporary bonds with the substrate (binding site) and residues that catalyse a reaction of that substrate (catalytic site).
Enzymes are highly selective catalysts, meaning that each enzyme only speeds up a specific reaction. The molecules that an enzyme works with are called substrates. The substrates bind to a region on the enzyme called the active site. There are two theories explaining the enzyme-substrate interaction.