| Title: |
Molten globule-like transition state of protein barnase measured with calorimetric force spectroscopy |
| Authors: |
Marc Rico-Pasto; Annamaria Zaltron; Sebastian J. Davis; Silvia Frutos; Felix Ritort |
| Contributors: |
Rico-Pasto, Marc; Zaltron, Annamaria; Davis, Sebastian J.; Frutos, Silvia; Ritort, Felix |
| Publisher Information: |
National Academy of Sciences |
| Publication Year: |
2022 |
| Collection: |
Padua Research Archive (IRIS - Università degli Studi di Padova) |
| Subject Terms: |
folding; molten globule; protein; thermodynamic; transition state |
| Description: |
Understanding how proteins fold into their native structure is a fundamental problem in biophysics, crucial for protein design. It has been hypothesized that the formation of a molten globule intermediate precedes folding to the native conformation of globular proteins; however, its thermodynamic properties are poorly known. We perform single-molecule pulling experiments of protein barnase in the range of 7 ◦C to 37 ◦C using a temperature-jump optical trap. We derive the folding free energy, entropy and enthalpy, and heat capacity change (ΔCp = 1,050 ± 50 cal/mol·K) at low ionic strength conditions. From the measured unfolding and folding kinetic rates, we also determine the thermodynamic properties of the transition state, finding a significant change in ΔCp (∼90%) between the unfolded and the transition states. In contrast, the major change in enthalpy (∼80%) occurs between the transition and native states. These results highlight a transition state of high energy and low configurati. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
info:eu-repo/semantics/altIdentifier/pmid/35271392; info:eu-repo/semantics/altIdentifier/wos/WOS:000772224400005; volume:119; issue:11; journal:PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA; https://hdl.handle.net/11577/3439497 |
| DOI: |
10.1073/pnas.2112382119 |
| Availability: |
https://hdl.handle.net/11577/3439497; https://doi.org/10.1073/pnas.2112382119 |
| Rights: |
info:eu-repo/semantics/openAccess |
| Accession Number: |
edsbas.EA8548C5 |
| Database: |
BASE |