Reduction of protein volume and compressibility by macromolecular cosolvents: dependence on the cosolvent molecular weight

• Published in: Biochimica et biophysica acta Vol. 1382; no. 1; pp. 151 - 156
• Main Authors: Almagor, Ada, Priev, Aba, Barshtein, Gregory, Gavish, Benjamin, Yedgar, Saul
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.01.1998
• Subjects: Adiabatic compressibility; Animals; Dextrans - chemistry; Glycerol - chemistry; Horses; Macromolecular cosolvents; Molecular Weight; Myoglobin; Myoglobin - chemistry; Pressure; Protein specific volume; Proteins - chemistry; Regression Analysis; Solvents - chemistry; Sucrose - chemistry; Viscosity; Myoglobin; Protein specific volume; Macromolecular cosolvents; Adiabatic compressibility
• ISSN: 0167-4838; 0006-3002; 1879-2588
• DOI: 10.1016/S0167-4838(97)00174-X

The partial specific volume ( V) and adiabatic compressibility ( β) of myoglobin have been shown to be reduced by small cosolvents such as glycerol (A. Priev, A. Almagor, S. Yedgar, B. Gavish, Biochemistry 35 (1996) 2061–2066). To elucidate the effect of the cosolvent size on these protein properties, in the present study we determined V and β of myoglobin in solutions containing a homologous cosolvent series from sucrose to dextran - 500 (M.W. 500 000). It was found that in addition to the expected effect of the cosolvent concentration, V and β decrease with increasing cosolvent M.W. This suggests that structural properties of the cosolvent contribute to its effect on the protein interior.