Adenosine Triphosphate (ATP) (C₁₀H₁₆N₅O₁₃P₃) — Properties, Uses & Safety

Overview

Adenosine triphosphate (ATP) is often called the universal energy currency of the cell, and for good reason — virtually every energy-requiring process in living organisms is powered by ATP. With the molecular formula C10H16N5O13P3 and a molar mass of 507.18 g/mol, ATP is a complex nucleotide consisting of three components: the nitrogenous base adenine, the five-carbon sugar ribose, and a chain of three phosphate groups. It is the triphosphate group that gives ATP its energy-storing capability. The bonds between the phosphate groups are often called high-energy bonds because their hydrolysis releases a significant amount of free energy. When ATP is hydrolyzed to ADP (adenosine diphosphate) and inorganic phosphate (Pi), approximately 30.5 kJ/mol of energy is released under standard conditions (ATP + H2O → ADP + Pi + energy). This energy drives muscle contraction, nerve impulse transmission, active transport across cell membranes, biosynthesis of macromolecules, and countless other cellular processes. The human body contains only about 250 grams of ATP at any given time, but it recycles this supply so rapidly that a person produces and consumes roughly their own body weight in ATP every day. ATP is regenerated from ADP through cellular respiration (primarily oxidative phosphorylation in mitochondria) and photophosphorylation in chloroplasts. The chemiosmotic theory, proposed by Peter Mitchell (who won the 1978 Nobel Prize for this work), explains how the proton gradient across the inner mitochondrial membrane drives ATP synthase — a remarkable molecular machine that rotates like a turbine to synthesize ATP. Beyond energy transfer, ATP serves as a signaling molecule (purinergic signaling), a building block for RNA synthesis, and a substrate for kinase enzymes that regulate cellular processes through phosphorylation. ATP has no significant GHS hazards in its pure form. For chemistry students, ATP connects multiple disciplines: it illustrates phosphoanhydride bond chemistry, thermodynamics and free energy (Gibbs free energy calculations), coupled reactions (how energetically unfavorable reactions are driven by ATP hydrolysis), enzyme catalysis, and the fundamental link between chemistry and biology. Understanding ATP is essential for grasping how living systems harvest, store, and utilize chemical energy — a central theme in both chemistry and biology curricula.

IUPAC Name

[(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl (hydroxy-phosphonooxyphosphoryl) hydrogen phosphate

CAS Number

56-65-5

PubChem CID

5957

Molecular Formula

C₁₀H₁₆N₅O₁₃P₃

Molar Mass

507.18 g/mol

State at STP

solid

Appearance

White powder