Protein Ionizable Groups: pK Values and Their Contribution to Protein Stability and Solubility

Abstract

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.

A Novel Dominant Hyperekplexia Mutation Y705C Alters Trafficking and Biochemical Properties of the Presynaptic Glycine Transporter GlyT2

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Sequential pH-driven dimerization and stabilization of the N-terminal domain enables rapid spider silk formation

“…Theoretical prediction of titratable residues within a protein is usually complicated as pK a values can be significantly perturbed depending on local environment 18 . Since clustering of acidic residues frequently leads to elevated pK a values 19 , the closely located conserved residues, E79, E84 and D40, were previously investigated.…”

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