Aggregation characteristics of ovalbumin in β-sheet conformation determined by spectroscopy

✍ Scribed by Raimon Sabaté; Joan Estelrich

• Publisher: Wiley (John Wiley & Sons)
• Year: 2002
• Tongue: English
• Weight: 157 KB
• Volume: 67
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.10061

✦ Synopsis

Abstract

Protein misfolding and aggregation are involved in a number of the so‐called “conformational” diseases (e.g., transmissible spongiform encephalopathies and Alzheimer disease). The development of rational strategies to interfere with aggregation is a potential therapeutic approach that requires complete knowledge of the aggregation process. We studied the aggregation of ovalbumin in β‐sheet conformation using mainly the spectral changes in the spectra of two dyes (Congo Red and pinacyanol) caused by the aggregates. We assumed a linear model of polymerization that fit to the experimental data. The critical aggregation constant, concentration of half‐aggregation, nucleation parameter, growth parameter, and number of aggregation and free energy changes (total and per residue) were determined as aggregation‐related parameters. β‐Ovalbumin aggregates in a cooperative way. Moreover, the differences between such parameters obtained with Congo Red and pinacyanol suggest that each dye interacts with the protein in its own way. © 2002 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 67: 113–120, 2002