Delineation of Solution Burst-Phase Protein Folding Events by Encapsulating the Proteins in Silica Gels
| Autor: | Seiichi Tsukamoto, Masamichi Ikeguchi, Takahiro Okabe, Kazuo Fujiwara, Naoya Shibayama |
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| Rok vydání: | 2014 |
| Předmět: |
Models
Molecular Protein Folding Circular dichroism Globular protein Silica Gel Lactoglobulins Biochemistry Protein Structure Secondary Avian Proteins chemistry.chemical_compound Native state Animals Humans Horses Beta-lactoglobulin Protein secondary structure chemistry.chemical_classification biology Chemistry Silica gel Burst phase Cytochromes c Enzymes Immobilized Kinetics Crystallography Immobilized Proteins Amino Acid Substitution Solubility Lactalbumin biology.protein Cattle Muramidase Mutant Proteins Protein folding Chickens Gels Lipocalin 1 |
| Zdroj: | Biochemistry. 53:3858-3866 |
| ISSN: | 1520-4995 0006-2960 |
| DOI: | 10.1021/bi5003647 |
| Popis: | Many studies have shown that during the early stages of the folding of a protein, chain collapse and secondary structure formation lead to a partially folded intermediate. Thus, direct observation of these early folding events is crucial if we are to understand protein-folding mechanisms. Notably, these events usually manifest as the initial unresolvable signals, denoted the burst phase, when monitored during conventional mixing experiments. However, folding events can be substantially slowed by first trapping a protein within a silica gel with a large water content, in which the trapped native state retains its solution conformation. In this study, we monitored the early folding events involving secondary structure formation of five globular proteins, horse heart cytochrome c, equine β-lactoglobulin, human tear lipocalin, bovine α-lactalbumin, and hen egg lysozyme, in silica gels containing 80% (w/w) water by CD spectroscopy. The folding rates decreased for each of the proteins, which allowed for direct observation of the initial folding transitions, equivalent to the solution burst phase. The formation of each initial intermediate state exhibited single exponential kinetics and Arrhenius activation energies of 14-31 kJ/mol. |
| Databáze: | OpenAIRE |
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