Title :

Formation of β-Lactoglobulin Aggregates from Quite, Unfolded Conformations upon Heat Activation

Author(s) :

Peres De Sa Peixoto Jr, Paulo [Auteur]
Institut National de la Recherche Agronomique [INRA]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Trivelli, Xavier [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle (UGSF) - UMR 8576
Unité de Glycobiologie Structurale et Fonctionnelle - UMR 8576 [UGSF]
Andre, Christophe [Auteur]
Institut National de la Recherche Agronomique [INRA]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Moreau, Anne [Auteur]
Institut National de la Recherche Agronomique [INRA]
Delaplace, Guillaume [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Institut National de la Recherche Agronomique [INRA]

Journal title :

Langmuir

Volume number :

35

Pages :

446-452

Publication date :

2018-12-19

English keyword(s) :

Calcium
Diffusion
Molecules
Aggregation
Conformation
dynamics
proteins

HAL domain(s) :

Sciences du Vivant [q-bio]/Ingénierie des aliments
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Sciences du Vivant [q-bio]/Biochimie, Biologie Moléculaire
Physique [physics]/Matière Condensée [cond-mat]/Matière Molle [cond-mat.soft]
Sciences de l'ingénieur [physics]/Génie des procédés

English abstract : [en]

In presence of calcium ions, β-lactoglobulin (BLG) unfolds and subsequently aggregates after heating. This process has important pharmaceutical and agroalimentary applications. Nowadays, the molecular mechanism of unfolding ...
Show more >In presence of calcium ions, β-lactoglobulin (BLG) unfolds and subsequently aggregates after heating. This process has important pharmaceutical and agroalimentary applications. Nowadays, the molecular mechanism of unfolding and BLG aggregation, and the role of calcium in the mechanism, is poorly understood. Actually, in most studies, data have been acquired at room temperature, after heating and after aggregation, which makes it difficult to establish a clear causal–temporal relation between calcium binding, heat, and aggregation. Thus, the goal of the present study is to get accurate, nanoscale data about the molecular events leading to BLG unfolding and calcium-dependent aggregation. The molecular transformation of BLG during heating has been investigated, using the NMR pulse field gradient technique, operating in a high field (900 MHz). Thanks to this technique, the molecular conformation of newly formed unfolded BLG molecules can be distinguished in a large pool of native ones. The present work shows that BLG at neutral pH at 65 °C displays fast, cooperative-like unfolding, in which no long-lived intermediary state (as a molten globule one) is detected, before aggregation. These data also indicate that calcium ions bind unfolded BLG in specific sites which might be a necessary feature to form the aggregate. Finally, these data also provide an NMR-based methodology to monitor the rate of protein unfolding using NMR.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
ENSCL
CNRS
INRA

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Processus aux Interfaces et Hygiène des Matériaux (PIHM)

Submission date :

2019-05-17T09:25:17Z
2021-01-18T10:40:22Z