Magnesium-adenosine triphosphate complex (Mg-ATP)

Magnesium-adenosine triphosphate (Mg-ATP) is the physiologically active form of adenosine triphosphate within the cellular environment. Because the triphosphate chain of ATP carries multiple negative charges, it requires the coordination of a divalent cation, typically magnesium (Mg2+), to stabilize its structure and allow for efficient interaction with the binding pockets of enzymes [1]. This complex serves as the universal energy currency and a critical substrate for a vast array of enzymes, including kinases, ATPases, and DNA/RNA polymerases [2]. In these enzymatic reactions, the magnesium ion helps orient the ATP molecule and polarize the phosphate groups to facilitate nucleophilic attack during phosphoryl transfer [3]. While Mg-ATP itself is not typically the primary therapeutic target, it is the endogenous ligand that many small-molecule drugs, such as ATP-competitive kinase inhibitors, seek to displace to achieve therapeutic effects in diseases like cancer and inflammatory disorders [4]. Dysregulation of Mg-ATP levels or the Mg2+:ATP ratio is associated with various metabolic and mitochondrial pathologies, making its maintenance vital for cellular homeostasis [5]. Consequently, understanding the dynamics of this complex is essential for drug design, particularly in optimizing the binding affinity of inhibitors that must compete with high intracellular concentrations of Mg-ATP [6].

Other names

MgATPMagnesium ATPMg2+:ATPAdenosine 5'-triphosphate magnesium saltMagnesium adenosine 5'-triphosphate

Competitive inhibition of the ATP-binding site in kinases and ATPases; substrate for phosphoryl transfer reactions