ovalbumin and kinetensin

The molecular properties of egg white ovalbumin adsorbed at the air/water interface were studied using infrared reflection absorption spectroscopy (IRRAS) and time-resolved fluorescence anisotropy (TRFA) techniques. Ovalbumin adsorbed at the air/water interface adopts a characteristic partially unfolded conformation in which the content of the beta-sheet is 10% lower compared to that of the protein in bulk solution. Adsorption to the interface leads to considerable changes in the rotational dynamics of ovalbumin. The results indicate that the end-over-end mobility of the ellipsoidal protein becomes substantially restricted. This is likely to reflect a preferential orientation of the protein at the interface. Continuous compression of surface layers of ovalbumin causes local aggregation of the protein, resulting in protein-network formation at the interface. The altered protein-protein interactions contribute to the strong increase in surface pressure observed.

Topics: Adsorption; Air; Colloids; Egg Proteins; Oligopeptides; Ovalbumin; Protein Conformation; Protein Structure, Secondary; Spectrometry, Fluorescence; Spectrophotometry, Infrared; Structure-Activity Relationship; Surface Properties; Surface Tension; Water