Metal ions modulate thermal aggregation of betalactoglobulin: a join chemical and physical characterization
Abstract Molecular basis of the role played by Cu 2 + and Zn 2 + ions during the thermal aggregation processes of beta-lactoglobulin (BLG) was studied by using a joint application of different techniques. In particular, Raman spectroscopy was very useful in identifying the different effects caused by the two metals at molecular level (i.e. changes in His protonation state, disulfides bridge conformation, and micro-environment of aromatic residues), evidencing the primary importance of the protein charge distribution during the aggregation process. Both metal ions are able to act on this factor and favor the protein aggregation, but Zn 2 + is able to alter the natural conformational state of…
Influence of metal ions on thermal aggregation processes of globular proteins
Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies, where the protein deposition occurs. The idea arises from the finding that increased metal concentrations (mainly copper, iron and zinc) are present in the brains of Alzheimer's disease patients both in the amyloid plaques and in the cortical tissue. Cu2+ and Zn2+ metals ions have a different physiological role and it has been observed that, in vitro, both promote (zinc more than copper) aggregation in amyloid fibrils and/or in amorphous aggregates. In addition, studying aggregation protein process can be of interest also in the field of biotechnologies like the food technology, since most p…
Chemical and physical characterization of thermal aggregation of model proteins modulated by zinc(II) and copper(II) ions
BACKGROUND: Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies, where the protein deposition occurs, and in the biotechnology field like the food technology where many processes in food manufacturing are based on thermal treatments. OBJECTIVE: The influence of Cu2+ or Zn2+ ions on the thermal aggregation process of Bovine beta-lactoglobulin (BLG) and Bovine Serum Albumin (BSA), two protein models, was studied with the aim of delineating the role of these ions in the protein aggregation kinetics and to clarify the related molecular mechanisms. METHODS: The protein structure changes were monitored by Raman spectroscopy, whereas the aggregate gr…
Influence of metal ions on thermal aggregation of bovine serum albumin: aggregation kinetics and structural changes
Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies. In this work the effects of Cu(II) and Zn(II) ions on heat-induced structural modifications of bovine serum albumin (BSA) were studied, with the aim of delineating the role of these ions in the early stages of proteins aggregation kinetics. A joint application of different techniques was used. The aggregate growth was followed by dynamic light scattering measurements, whereas the conformational changes occurring in the protein structure were monitored by Raman and IR spectroscopy. Both in absence and in presence of metal ions, heating treatment gave rise to b-structures to the detriment of a…