Residue-Specific Kinetic Insights into the Transition State in Slow Polypeptide Topological Isomerization by NMR Exchange Spectroscopy
| Autor: | Daisuke Fujinami, Seiichiro Hayashi, Daisuke Kohda |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Quantitative Biology::Biomolecules
Chemistry Enthalpy Cooperativity Free-energy relationship Topology Kinetics Isomerism Thermodynamics General Materials Science Protein folding Physical and Theoretical Chemistry Peptides Nuclear Magnetic Resonance Biomolecular Isomerization Two-dimensional nuclear magnetic resonance spectroscopy Equilibrium constant Entropy (order and disorder) |
| Zdroj: | The Journal of Physical Chemistry Letters. 12:10551-10557 |
| ISSN: | 1948-7185 |
| DOI: | 10.1021/acs.jpclett.1c02387 |
| Popis: | The characterization of the transition state is a central issue in biophysical studies of protein folding. NMR is a multiprobe measurement technique that provides residue-specific information. Here, we used exchange spectroscopy to characterize the transition state of the two-state slow topological isomerization of a 27-residue lantibiotic peptide. The exchange kinetic rates varied on a per-residue basis, indicating the reduced kinetic cooperativity of the two-state exchange, as well as the previously observed reduced thermodynamic cooperativity. Furthermore, temperature-dependent measurements revealed large variations in the activation enthalpy and entropy terms among residues. Interestingly, we found a linear relationship between the logarithm of the equilibrium constants and that of the exchange rates. Because the data points are derived from amino acid residues in one polypeptide chain, we refer to the linear relationship as the residue-based linear free energy relationship (rbLFER). The rbLFER offers information about the transition state of the two-state exchange. |
| Databáze: | OpenAIRE |
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