How is the protein melting point (Tm) determined
The Tm is the melting point of a protein, meaning it is the temperature at which 50% of the protein population is unfolded while the other half is still folded.
The Tm is determined from the unfolding profile of a protein as follows:
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PR.Panta Analysis allows application of Regions of Interest (RoI). Within regions of interest, a thermodynamic fit can be applied to the data. From the fit, a Tm can be derived.
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Please note that strictly speaking, thermodynamic parameters should only be extracted from equilibrium measurements, which thermal unfolding measurements typically are not.
Tm values may differ from IP values (see below) if the baselines are not horizontal.
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Please note that strictly speaking, thermodynamic parameters should only be extracted from equilibrium measurements, which thermal unfolding measurements typically are not.
- In addition to Tms, PR.Panta Analysis and PR.Panta Control software automatically calculate inflection points (IPs), which are used for the same purposes as Tms, and are often called Tms by convention. It is however important not to confuse the two. IPs are derived directly from the data without fitting.