ATPhüdrolüüs

ATPhüdrolüüs is the process by which adenosine triphosphate (ATP) is broken down into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy that cells can use to perform various functions. The hydrolysis of ATP is a fundamental reaction in cellular metabolism, powering processes such as muscle contraction, nerve impulse transmission, and the synthesis of molecules. The energy released is not directly used but is typically coupled to other endergonic reactions, making them thermodynamically favorable.

The reaction can be represented as: ATP + H2O → ADP + Pi + Energy. This process is catalyzed by enzymes called ATPases. While the overall reaction is exergonic, meaning it releases energy, the precise amount of energy released can vary depending on cellular conditions, such as pH and ion concentrations. This variability is crucial for regulating cellular energy expenditure. ADP can then be rephosphorylated back to ATP, often through processes like cellular respiration and photosynthesis, thus completing the ATP cycle. This continuous cycle of ATP hydrolysis and synthesis is essential for life.