Premium
Removal of surface charge‐charge interactions from ubiquitin leaves the protein folded and very stable
Author(s) -
Loladze Vakhtang V.,
Makhatadze George I.
Publication year - 2002
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1110/ps.29902
Subject(s) - protonation , protein folding , chemistry , folding (dsp implementation) , charge (physics) , surface charge , site directed mutagenesis , mutagenesis , static electricity , protein engineering , solvent , protein stability , chemical stability , ubiquitin , stereochemistry , computational chemistry , crystallography , biochemistry , mutation , organic chemistry , mutant , ion , enzyme , physics , quantum mechanics , electrical engineering , gene , engineering
Abstract The contribution of solvent‐exposed charged residues to protein stability was evaluated using ubiquitin as a model protein. We combined site‐directed mutagenesis and specific chemical modifications to first replace all Arg residues with Lys, followed by carbomylation of Lys‐amino groups. Under the conditions in which all carboxylic groups are protonated (at pH 2), the chemically modified protein is folded and very stable (ΔG = 18 kJ/mol). These results indicate that surface charge–charge interactions are not an essential fundamental force for protein folding and stability.