TB-500 10mg

Molecular structure

Thymosin beta-4 is a 43-residue peptide with a defined primary amino-acid sequence. Unlike a compact globular protein, its conformation is relatively flexible and can depend strongly on its molecular environment and binding partners.

An important structural region is associated with actin binding. Actin is a protein that polymerizes into filaments and participates in cytoskeletal organization. Thymosin beta-4 interacts with actin monomers and can influence their availability for filament formation.

The sequence contains both polar and nonpolar residues, allowing it to interact with aqueous solvents and with selected protein surfaces. Its single sulfur-containing methionine residue is a potential site for oxidation.

Physicochemical properties

Its solution conformation is not adequately represented by one rigid structure under all conditions. Temperature, pH, solvent composition, and interactions with other proteins can alter its conformational ensemble.

Oxidation of methionine can produce a mass shift of approximately 16 Da. This illustrates why chemical identity and sample integrity are separate questions.

Biochemical mechanisms

The interaction between thymosin beta-4 and actin is a well-characterized molecular relationship. Other reported interactions involving signaling proteins and cellular pathways vary in the strength of their evidence.

Scientific evidence

Full-length thymosin beta-4 must be distinguished from shorter fragments derived from it. The full-length sequence, its molecular mass, and the presence of the complete 43-residue chain are key analytical identifiers.

TB500 is supplied strictly for research use only and is not intended for human or animal consumption, clinical application, diagnostic use, or therapeutic purposes.