A Second Look at Mini-Protein Stability: Analysis of FSD-1 Using Circular Dichroism, Differential Scanning Calorimetry, and Simulations
AUTOR(ES)
Feng, Jianwen A.
FONTE
The Biophysical Society
RESUMO
Mini-proteins that contain <50 amino acids often serve as model systems for studying protein folding because their small size makes long timescale simulations possible. However, not all mini-proteins are created equal. The stability and structure of FSD-1, a 28-residue mini-protein that adopted the ββα zinc-finger motif independent of zinc binding, was investigated using circular dichroism, differential scanning calorimetry, and replica-exchange molecular dynamics. The broad melting transition of FSD-1, similar to that of a helix-to-coil transition, was observed by using circular dichroism, differential scanning calorimetry, and replica-exchange molecular dynamics. The N-terminal β-hairpin was found to be flexible. The FSD-1 apparent melting temperature of 41°C may be a reflection of the melting of its α-helical segment instead of the entire protein. Thus, despite its attractiveness due to small size and purposefully designed helix, sheet, and turn structures, the status of FSD-1 as a model system for studying protein folding should be reconsidered.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2776296Documentos Relacionados
- Conformational state of DNA in chromatin subunits. Circular dichroism, melting, and ethidium bromide binding analysis.
- Nucleic acid vibrational circular dichroism, absorption, and linear dichroism spectra. I. A DeVoe theory approach.
- Thermal stability of PNA/DNA and DNA/DNA duplexes by differential scanning calorimetry.
- B850 pigment-protein complex of Rhodopseudomonas sphaeroides: Extinction coefficients, circular dichroism, and the reversible binding of bacteriochlorophyll
- Somatostatin conformation: evidence for a stable intramolecular structure from circular dichroism, diffusion, and sedimentation equilibrium.
