Structure and Properties of Adsorption Layers of β-Casein Formed from Guanidine Hydrochloride Rich Solutions

Citations Over TimeTop 11% of 2001 papers

Abstract

Adsorption layers of β-casein formed at the interface between air and a buffer including various concentrations of guanidine hydrochloride (GuHCl) were studied by neutron reflectivity and by bubble tensiometry. A transition in the structure and in the properties of the adsorption layer seems to occur around a GuHCl concentration of 1.5 M. The data are interpreted assuming that the adsorbed protein molecules behave like multiblock copolymers with alternating hydrophilic and hydrophobic sequences. Below the transition, the hydrophilic coils and the hydrophobic two-dimensional blocks have a fractal dimension larger than that beyond the transition where they have the features of either two-dimensional or three-dimensional excluded volume coils. The effect of temperature on these phenomena indicates that they are not dominated by hydrophobic interactions. Thus, the attractions between amino acids which are broken by GuHCl might be hydrogen bonds which are frequently encountered in the secondary structure of polypeptide chains. These results show that even with the flexible polypeptide chain of β-casein, interactions between amino acids contribute significantly to the structure of the adsorption layer formed from a buffer devoid of denaturing agent.

Related Papers

• → Prolonged lifetime of the 410-nm intermediate of bacteriorhodopsin in the presence of guanidine hydrochloride(1977)40 cited
• → A Dilatometric Study of the Denaturation of Lysozyme by Guanidine Hydrochloride and Hydrochloric Acid(1972)29 cited
• Unfolding of Bovine Heart Cytochrome c Induced by Urea and Guanidine Hydrochloride(2011)
• The Influence of Temperature,Urea and Guanidine Hydrochloride On the Fluorescence Spectrum of Tobacco PR-1a(2015)
• Interactions of biocidal guanidine hydrochloride polymer analogs with model membranes： a comparative biophysical study(2011)