ATP synthase is an enzyme that plays a vital role in the addition of a phosphate to ADP, or adenosine diphosphate, to form ATP, or adenosine triphosphate. The enzyme is located within the mitochondria of a cell, where the synthesis of ATP occurs.
ATP synthase catalyzes the reaction to combine ADP, or adenosine diphosphate, with a single phosphate unit to yield ATP. The enzyme itself is a complex machine composed of an ion pump and two molecular motors that power the enzyme.
The reaction is stimulated when protons are pushed through the cell membrane's proton gradient — the proton gradient is located in the mitochondria. The hydrogen ions present in the gradient act as a source of power for the ATP synthase and assists in the formation of ATP by adding one phosphate to the adenosine diphosphate already present.
ATP is a powerful energy source stored in the nucleoplasm and cytoplasm of cells. The molecule is pertinent for cellular operations to occur. Energy from ATP is released when the molecule loses a phosphate group, which thus forms ADP. The process is then recycled back to ATP with the help of ATP synthase as the ADP molecule passes through the mitochondria. ADP and ATP play an integral role in the production and use of energy. Their cyclical relationship allows the cell's energy to be efficiently restored.