What is the basic mechanism of enzyme reaction?

An enzyme reaction is initiated when a substrate is attracted to the enzyme’s active site. Catalytic residues in the active site bind to the substrate via non-covalent bonds, eventually breaking down the substrate or combining the substrate with other molecules to form an enzyme-substrate complex. The enzyme allows the newly formed product to dissociate from its surface. It then returns to its original state and is free to bind to another molecule of the substrate.