Variations in Proteins Dielectric Constants

Muhamed Amin*, Jochen Küpper

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

21 Citations (Scopus)
104 Downloads (Pure)


Using a new semi-empirical method for calculating molecular polarizabilities and the Clausius−Mossotti relation, we calculated the static dielectric constants of dry proteins for all structures in the protein data bank (PDB). The mean dielectric constant of more than 150,000 proteins is (Formula presented.) with a standard deviation of 0.04, which agrees well with previous measurement for dry proteins. The small standard deviation results from the strong correlation between the molecular polarizability and the volume of the proteins. We note that non-amino acid cofactors such as Chlorophyll may alter the dielectric environment significantly. Furthermore, our model shows anisotropies of the dielectric constant within the same molecule according to the constituents amino acids and cofactors. Finally, by changing the amino acid protonation states, we show that a change of pH does not have a significant effect on the dielectric constants of proteins.

Original languageEnglish
Pages (from-to)691-694
Number of pages4
Issue number6
Publication statusPublished - Jun-2020


  • dielectric constants
  • proteins
  • semi-empirical methods
  • electrostatic interactions
  • molecular polarizabilities

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