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Updated: May 13, 2026
08:07
Single Molecule Fluorescence Energy Transfer Study of Ribosome Protein Synthesis
Published on: July 6, 2021
Electrostatic effect of the ribosomal surface on nascent polypeptide dynamics
Anders M Knight1, Peter H Culviner, Neşe Kurt-Yilmaz
1Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
ACS Chemical Biology
|March 23, 2013
Summary
Nascent polypeptides near the ribosome exhibit enhanced flexibility, influencing protein folding. The ribosome
Area of Science:
- Molecular biology
- Biophysics
- Protein biogenesis
Background:
- Protein folding mechanisms in vivo remain largely unknown.
- Nascent polypeptides interact with the negatively charged ribosomal surface upon emerging from the exit tunnel.
Purpose of the Study:
- Investigate how the ribosomal surface influences nascent polypeptide dynamics.
- Characterize the behavior of intrinsically disordered proteins near the ribosome.
Main Methods:
- Utilized the intrinsically disordered protein PIR and its charged mutants.
- Analyzed polypeptide populations based on spatial bias and dynamics.
Main Results:
- Identified two populations: spatially biased and highly dynamic.
- More negatively charged polypeptides showed increased dynamic populations.
- Proximity to the ribosome enhanced molecular flexibility in a subpopulation, akin to denaturants.
- A spatially biased population persisted, suggesting a protective 'sticking' effect against aggregation.
Conclusions:
- Ribosomal proximity significantly impacts nascent protein dynamics beyond peptide bond formation.
- Enhanced flexibility may aid in proper structural channeling and prevent kinetic trapping.
- The ribosome plays a crucial role in protecting nascent proteins from cotranslational aggregation.
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