Magnesium-dependent enzyme and nucleotide complex

Magnesium-dependent enzyme and nucleotide complexes are biochemical assemblies where magnesium ions (Mg2+) serve as essential cofactors for enzymes that interact with nucleotides like ATP, GTP, DNA, or RNA. These complexes are fundamental to life, as magnesium typically coordinates with the negatively charged phosphate groups of the nucleotide, facilitating proper orientation and stabilizing the transition state during catalytic reactions (Steitz, 1998). This broad category encompasses a wide variety of enzymes, including DNA and RNA polymerases, kinases, ATPases, and viral integrases (NIH, 2022). In the context of drug discovery, these complexes are often targeted by small molecules that utilize a metal-chelating motif to bind the active-site magnesium ions, thereby inhibiting the enzyme's function. A prominent example is the class of integrase strand transfer inhibitors (INSTIs) used to treat HIV, which specifically target the Mg2+ ions in the viral integrase-DNA complex (Grobler et al., 2002). Because this term refers to a general structural and functional motif shared by hundreds of distinct enzymes rather than a single protein, it is classified as a broad enzyme category rather than a specific therapeutic target.

Other names

Mg2+-dependent enzymesMetal-dependent nucleotide-binding enzymesMagnesium-cofactor enzyme complexesTwo-metal-ion mechanism enzymes

Chelation of active-site magnesium ions or competitive inhibition of nucleotide binding sites to disrupt catalytic function.