Lysozyme Net Charge and Ion Binding in Concentrated Aqueous Electrolyte Solutions

Journal Article · Mon Feb 01 04:00:00 EST 1999 · Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry

DOI:https://doi.org/10.1021/jp983852i· OSTI ID:1183892

Kuehner, Daniel E.; Engmann, Jan; Fergg, Florian; Wernick, Meredith; Blanch, Harvey W.; Prausnitz, John M.

Hydrogen-ion titrations were conducted for hen-egg-white lysozyme in solutions of potassium chloride, over the range of pH 2.5 - 11.5 and for ionic strengths to 2. 0 M. The dependence of lysozyme's net proton charge, zP' on pH and ionic-strength in potassium-chloride solution is measured. From the ionic-strength dependence of zP' interactions of lysozynie with potassium and chloride ions are calculated using the molecular-thennodynamic theory of Fraaije and Lyklema 1. Lysozyme interacts preferentially with up to 12 chloride ions at pH 2.5. The observed dependence of ion-protein interactions on pH and ionic strength is explained in terms of electricdouble-layer theory. New experimental pKa data are reported for eleven ammo acids in potassium-chloride solutions of ionic strength to 3.0 M.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 1183892
• Report Number(s): LBNL--42717
• Journal Information: Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry, Journal Name: Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry Journal Issue: 8 Vol. 103; ISSN 1520-6106
• Country of Publication: United States
• Language: English