Towards the understanding of molecular mechanisms in the early stages of heat-induced aggregation of β-lactoglobulin AB

Reversible Unfolding of Bovine β-Lactoglobulin Mutants without a Free Thiol Group

“…Irreversible denaturation has been thought to arise from thiol-disulfide exchange caused by the free thiol of Cys-121. Indeed, the formation of intermolecular disulfide bridges by heat denaturation at neutral pH has been reported previously (27)(28)(29)(30). Even at pH 2.1, an incomplete recovery of CD spectra was observed in samples treated with 7 M urea (22).…”

Formation of Non-Native β-Lactoglobulin during Heat-Induced Denaturation

“…Integration of the monomeric peak gave the concentration of β-lactoglobulin monomers. The amount of aggregation was calculated by Comparing reversed-phase and GPC-HPLC allowed for the quantification of non-native monomers, some of which have been described previously 8,19 . Essentially these species were formed by the first step of the aggregation mechanism, whereby some irreversible unfolding and/or intramolecular disulfide interchange took place, which gave rise to a non-native monomer.…”

Heat-induced denaturation/aggregation of β-lactoglobulin A and B: kinetics of the first intermediates formed

“…Heat-induced changes of b-lg have been widely studied under a wide range of pH, ionic strength and protein concentration conditions (Sawyer, 1968;Roefs & de Kruif, 1994;Qi et al, 1997;Bauer, Hansen, & Ogendal, 1998;Verheul, Roefs, & de Kruif, 1998;Shokker, Singh, Pinder, Norris, & Creamer, 1999;Bauer, Carrotta, Rischel, & Ogendal, 2000;Kitabatake, Wada, & Fujita, 2001;Hong & Creamer, 2002;Surroca, Haverkamp, & Heck, 2002). The genetic variants A and B of b-lg exhibit a marked difference in their heatinduced denaturation/aggregation behavior (Nielsen, Singh, & Latham, 1995;Shokker, Singh, & Creamer, 2000).…”