A possible relation between the salting-out behaviour of proteins and their surface hydrophobicity
Salahuddin, A.; Waseem, A.; Khan, M.Y.; Qasim, M.A.; Sibghatullah
Indian Journal of Biochemistry and Biophysics 20(3): 127-131
1983
ISSN/ISBN: 0301-1208 PMID: 6671670 Document Number: 213885
The solubilities of lysozyme, myoglobin, chymotrypsinogen A, pepsinogen, ovalbumin, conalbumin, bovine serum albumin and its 2 fragments comprised of domain I or III of the protein, in concentrated ammonium sulfate solution were studied at pH 7.0 and 30.degree. C under salting-out conditions. The salting-out parameters Ks and .beta. were determined for each protein from the solubility data. The possible dependence of these constants on the molecular and structural properties of a protein was examined. The parameters did not correlate with MW, amino acid composition or isoelectric points of a protein. The salting-out constant, Ks, of a protein is a function of surface hydrophobicity and .beta. correlates well with protein hydration.