TY - JOUR
T1 - Association of caseins with β-lactoglobulin influenced by temperature and calcium ions
T2 - A multi-parameter analysis
AU - Mohammad-Beigi, Hossein
AU - Wijaya, Wahyu
AU - Madsen, Mikkel
AU - Hayashi, Yuya
AU - Li, Ruifen
AU - Maria Rovers, Tijs Albert
AU - Jæger, Tanja Christine
AU - Buell, Alexander K.
AU - Hougaard, Anni Bygvrå
AU - Kirkensgaard, Jacob J.K.
AU - Westh, Peter
AU - Ipsen, Richard
AU - Svensson, Birte
PY - 2023/4
Y1 - 2023/4
N2 - Aggregation of the major whey protein in bovine milk, β-lactoglobulin (β-Lg) is strongly influenced by association with caseins (CNs). Here, by using combined differential scanning fluorimetry and dynamic light scattering, the conformational stability and aggregation propensity of β-Lg and three types of CNs (α, β and ĸCNs) as well as their mixture have been systematically evaluated at different temperatures and Ca2+ concentrations in a multi-parametric approach. While β-Lg was affected significantly through denaturation and resulting aggregation by heat treatment with little dependency on Ca2+, αCN and βCN were influenced considerably by Ca2+. Through modifying the aggregation of β-Lg, CNs showed a different chaperone-like activity among the three types which were markedly dependent on the temperature and Ca2+ concentration. The presence of CNs resulted in smaller mixed aggregates compared to pure β-Lg aggregates, mainly through interaction of CNs with unfolded β-Lg and also by influencing the process of β-Lg unfolding. This was further confirmed by small angle X-ray scattering and isothermal titration calorimetry indicating that Ca2+ enhanced the interaction between β-Lg and CNs. Our experimental approach sheds light on molecular understanding of CN- β-Lg interactions and provides insight into how micro-structural assembly of milk proteins can be modulated to enable different functionalities in milk-based products.
AB - Aggregation of the major whey protein in bovine milk, β-lactoglobulin (β-Lg) is strongly influenced by association with caseins (CNs). Here, by using combined differential scanning fluorimetry and dynamic light scattering, the conformational stability and aggregation propensity of β-Lg and three types of CNs (α, β and ĸCNs) as well as their mixture have been systematically evaluated at different temperatures and Ca2+ concentrations in a multi-parametric approach. While β-Lg was affected significantly through denaturation and resulting aggregation by heat treatment with little dependency on Ca2+, αCN and βCN were influenced considerably by Ca2+. Through modifying the aggregation of β-Lg, CNs showed a different chaperone-like activity among the three types which were markedly dependent on the temperature and Ca2+ concentration. The presence of CNs resulted in smaller mixed aggregates compared to pure β-Lg aggregates, mainly through interaction of CNs with unfolded β-Lg and also by influencing the process of β-Lg unfolding. This was further confirmed by small angle X-ray scattering and isothermal titration calorimetry indicating that Ca2+ enhanced the interaction between β-Lg and CNs. Our experimental approach sheds light on molecular understanding of CN- β-Lg interactions and provides insight into how micro-structural assembly of milk proteins can be modulated to enable different functionalities in milk-based products.
KW - Aggregation propensity
KW - Caseins
KW - Chaperone
KW - Colloidal stability
KW - Milk
KW - β-lactoglobulin
U2 - 10.1016/j.foodhyd.2022.108373
DO - 10.1016/j.foodhyd.2022.108373
M3 - Journal article
SN - 0268-005X
VL - 137
JO - Food Hydrocolloids
JF - Food Hydrocolloids
M1 - 108373
ER -