Protein ionizable groups: pK values and their contribution to protein stability and solubility

J Biol Chem. 2009 May 15;284(20):13285-9. doi: 10.1074/jbc.R800080200. Epub 2009 Jan 21.


The structure, stability, solubility, and function of proteins depend on their net charge and on the ionization state of the individual residues. Consequently, biochemists are interested in the pK values of the ionizable groups in proteins and how these pK values depend on their environment. We review what has been learned about pK values of ionizable groups in proteins from experimental studies and discuss the important contributions they make to protein stability and solubility.

Publication types

  • Historical Article
  • Review

MeSH terms

  • History, 20th Century
  • Protein Conformation*
  • Protein Stability*
  • Proteins / chemistry*
  • Proteins / history
  • Solubility
  • Static Electricity


  • Proteins