Pharmaceutica Analytica Acta

Abstract

Fluorescence Study of Bovine β-Lactoglobulin

Jihad René Albani

β-Lactoglobulin consists of a single polypeptide of 162 amino acid residues (Mr=18,400). Tertiary structure of β-lactoglobulin possesses a pocket (calyx) where hydrophobic ligands can easily bind. The protein normally exists as a dimer, each monomer having one free cysteine and two disulphide bridges. Quaternary structure of the protein varies with the pH. For example, at pH 2, β-lactoglobulin is in a molten globule state, stable although partially unfolded, and at pH 12 the protein is denatured. At some pH, mixtures of both monomeric and dimeric forms are found.