Extended Law of Corresponding States Applied to Solvent Isotope Effect on a Globular Protein

• Investigating proteins with techniques such as NMR or neutron scattering frequently requires the partial or complete substitution of D2O for H2O as a solvent, often tacitly assuming that such a solvent substitution does not significantly alter the properties of the protein. Here, we report a systematic investigation of the solvent isotope effect on the phase diagram of the lens protein gamma B-crystallin in aqueous solution as a model system exhibiting liquid-liquid phase separation. We demonstrate that the observed strong variation of the critical temperature T-c can be described by the extended law of corresponding states for all H2O/D2O ratios, where scaling of the temperature by T-c or the reduced second virial coefficient accurately reproduces the binodal, spinodal, and osmotic compressibility. These findings highlight the impact of H2O/D2O substitution on gamma B-crystallin properties and warrant further investigations into the universality of this phenomenon and its underlying mechanisms.

Subject headings

NATURVETENSKAP  -- Kemi -- Fysikalisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Physical Chemistry (hsv//eng)

NATURVETENSKAP  -- Kemi -- Teoretisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Theoretical Chemistry (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)