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Updated: Aug 9, 2026
11:19
Isolation of Translating Ribosomes Containing Peptidyl-tRNAs for Functional and Structural Analyses
Published on: February 25, 2011
Ribosomal protein bL27 protects translating ribosomes from tmRNA-SmpB
Divyasorubini Seerpatham1, George Wanes2,3, Chathuri Pathirage4
1Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, USA.
Science Advances
|August 7, 2026
Summary
Bacterial ribosomal protein bL27 prevents transfer-messenger RNA (tmRNA) from disrupting protein synthesis. This discovery reveals a crucial role for bL27 in regulating bacterial ribosome rescue mechanisms.
Area of Science:
- Molecular Biology
- Bacterial Genetics
- Biochemistry
Background:
- Bacterial ribosomal protein bL27 is essential but its function in translation is poorly understood.
- The amino terminus of bL27 is near the peptidyl transfer center, a key site for protein synthesis.
Purpose of the Study:
- To elucidate the role of bacterial ribosomal protein bL27 in protein synthesis.
- To investigate the interaction between bL27 and the trans-translation machinery.
Main Methods:
- Genetic manipulation (gene deletion) in bacteria.
- Biochemical assays of in vitro translation.
- Molecular dynamics simulations.
Main Results:
- Deletion of bL27 severely impacts bacterial viability, partially rescued by tmRNA deletion.
- tmRNA-SmpB inhibits protein synthesis on bL27-deficient ribosomes but not wild-type ribosomes.
- Molecular dynamics show bL27 hinders tmRNA movement on the ribosome.
Conclusions:
- Bacterial ribosomal protein bL27 plays a critical role in preventing interference from tmRNA-SmpB during protein synthesis.
- bL27 acts as a gatekeeper, ensuring tmRNA does not sterically hinder tRNA binding and function.
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