Enzymes catalyze chemical reactions by first binding to molecules and then lining them up in ways that increase the probability of the molecules exchanging atoms when they collide. Enzymes therefore allow scientists to control the exchange of atoms mechanically, as explained by Science Daily.
One way researchers have done this is by attaching a controllable molecular spring composed of DNA to an enzyme, which is simply a large protein. They then turned the enzyme on and off mechanically, which in turn controlled how fast the chemical reactions, or atom exchanges, occurred.
Different steps within the reactions were influenced in accordance with where on the enzyme the molecular spring was attached, as reported by UCLA Physics professor Giovanni Zocchi and his colleagues.
In general, enzymes make chemical bonds easier to manipulate by stretching or twisting molecules so the amount of activation energy normally required for reactions to occur, usually in the form of heat, stirring or shaking, is reduced or eliminated.
Different types of enzymes have different types of reactions they activate, and there are some enzymes that must be in particular environments or operate under certain sets of conditions to work well, if at all. Enzymes may also fail to catalyze chemical reactions if they suffer damage.