Transfer free energy (TFE) of amino acid side-chains from aqueous environment into lipid bilayers is an important energetic factor in determining the thermodynamic stability of a transmembrane protein (TMP), which is the basis for understanding TMP folding, membrane insertion, and structure-function relationship.

General Transfer Free Energy Profile (GeTFEP) is derived from β-barrel transmembrane proteins, and find to be applicable to α-helical transmembrane proteins as well [2]

For asymmetric GeTFEP profile, the transfer free energy \(TFE(d)\)of a sidechain can be calculated using

\( TFE(d) = \sum_{i=0}^3 p_i \times d^i \)

where \( d \) is the relative deepth in membrane whose value is in \( [-1,1] \)

For symmetric GeTFEP profile, \(TFE(d)\) can be calculated by

\( TFE(d) = \sum_{i=0}^3 p_i \times abs(d)^i \)

Coefficients