Structure of β-casein

Abstract

SUMMARYThe temperature and concentration dependent association of β-casein was studied by means of viscometry, gel filtration chromatography, electron microscopy, analytical ultracentrifugation and UV difference spectrophotometry. Degrees of polymerization of 12, 22 and 49 and free energies of association of –21, –23 and – 25 kJ/mole monomer were found at temperatures of 10, 15 and 20 °C respectively in 0·2 M Na phosphate buffer pH 6·7.Monomeric β-casein was not a completely random coil but became more compact with increasing temperature, due to hydrophobic interactions.