Interacting processes in protein coagulation

Abstract

A strong interest is currently focused on protein self-association and deposit. This usually involves conformational changes of the entire protein or of a fragment. It can occur even at low concentrations and is responsible for pathologies such as systemic amyloidosis, Alzheimer's and Prion diseases, and other neurodegenerative pathologies. Readily available proteins, exhibiting at low concentration self-association properties related to conformational changes, offer very convenient model systems capable of providing insight into this class of problems. Here we report experiments on bovine serum albumin, showing that the process of conformational change of this protein towards an intermediate form required for coagulation occurs simultaneously and interacts with two more processes: mesoscopic demixing of the solution and protein cross-linking. This pathway of three interacting processes allows coagulation even at very low concentrations, and it has been recently observed also in the case of a nonpeptidic polymer. It could therefore be a fairly common feature in polymer coagulation/gelation. Proteins 1999;37:116-120.

Synthetic chrysotile nanocrystals as a reference standard to investigate surface-induced serum albumin structural modifications

“…Bovine serum albumin (BSA), the major plasma protein, is a well-known globular protein; its secondary structure is essentially α-helical [18,19]. BSA tendency to aggregate into macromolecular assemblies [20] is reported to be related to conformational changes [21]. Surface adsorption of BSA on geoinspired stoichiometric chrysotile fibers has been recently investigated by a morphological and spectroscopic analysis, where the BSAcoated chrysotile nanocrystals exhibit evident modifications of BSA secondary structure [16].…”

Proteins in Saccharides Matrices and the Trehalose Peculiarity: Biochemical and Biophysical Properties

“…[182]. gregates of very low compactness, as observed in the literature [185]), is followed by a mainly Gaussian coil-like growth characterized by a fractal dimension d 2 and consistent with the formation of more compact aggregates, as already observed in previous studies on BSA aggregation [185,186]. The data show also that in dilute solutions the effect of sugars on protein aggregation is a water mediated a-specific effect and does not depend upon direct protein-sugar interactions [184].…”

Chemical, thermal and pH‐induced equilibrium unfolding studies of Fusarium solani lectin

“…During thermal denaturation, many proteins do not refold, due to aggregation of the unfolded state (34,35). The aggregation usually involves unfolding of the whole protein or of a specific domain and it is often attributed to the association of partially unfolded molecules (36,37). Hence, aggregation stabilizes the unfolded oligomers by reducing the energetically unfavorable interactions between water molecules and exposed hydrophobic patches in the protein.…”