What does Tm represent in protein denaturation?

In the context of protein denaturation, Tm refers to the melting temperature, which is the midpoint at which half of the protein's structures are denatured or unfolded. This temperature is a critical value because it indicates the stability of the protein; below this temperature, the protein is mostly in its native, functional form, while above it, a significant portion of the protein has undergone denaturation.

Tm is influenced by various factors, including the specific amino acid sequence of the protein, the presence of ligands or stabilizing agents, and the overall environment, such as pH and ionic strength. Therefore, identifying Tm as the midpoint of the denaturation reaction provides valuable insight into the stability and folding of proteins, ultimately helping to understand their function in biological systems.