dimerizing

Dimerizing is the process by which two molecular units join to form a dimer, a species composed of two subunits. Dimers can arise from identical units (homo-dimers) or from two different units (hetero-dimers). The association can be covalent, involving bonds such as disulfide linkages or other chemical bonds, or noncovalent, driven by interactions like hydrogen bonding, ionic forces, van der Waals contacts, or hydrophobic effects. Dimerization can be partial or complete and may be reversible or irreversible, depending on the nature of the bonding and conditions such as concentration, temperature, and solvent.

In chemistry and biochemistry, dimerization serves multiple roles. Covalent dimers often form through specific reactions or crosslinking and can be stable, impacting molecular stability and function. Noncovalent dimerization is common for many proteins and nucleic acid-binding molecules, where dimer formation can regulate activity, specificity, and binding affinity. Dimerization is frequently concentration-dependent, with higher concentrations favoring dimer formation, and it can be influenced by post-translational modifications or ligand binding. In materials science, dimerization can refer to the pairing of small organic or inorganic units that influences crystallization, reactivity, or optical properties.

Examples include the organic dimerization of cyclopentadiene to form dicyclopentadiene, a classic reversible example used in polymer precursors. In biochemistry, many proteins function as dimers; some transcription factors and receptors require dimerization for DNA binding or signaling. Detection and study of dimerization employ techniques such as spectroscopy, analytical ultracentrifugation, size-exclusion chromatography, cross-linking, and mass spectrometry, along with measurements of association constants to quantify the interaction.