Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 117, Issue 19, Pages 10271-10277Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.2002888117
Keywords
ribosome; translocation; viomycin
Categories
Funding
- Natural Science Foundation of China [31971226]
- Zhejiang Natural Science Foundation [LR20C050003]
- Fundamental Research Funds for the Central Universities [2018QN81010]
- Zhejiang University
- Thousand Young Talents Plan of China
- NIH [R35-GM118156]
- Robert L. Sinsheimer Chair
Ask authors/readers for more resources
Viomycin, an antibiotic that has been used to fight tuberculosis infections, is believed to block the translocation step of protein synthesis by inhibiting ribosomal subunit dissociation and trapping the ribosome in an intermediate state of intersubunit rotation. The mechanism by which viomycin stabilizes this state remains unexplained. To address this, we have determined cryo-EM and X-ray crystal structures of Escherichia coli 70S ribosome complexes trapped in a rotated state by viomycin. The 3.8-angstrom resolution cryo-EM structure reveals a ribosome trapped in the hybrid state with 8.6 degrees intersubunit rotation and 5.3 inverted perpendicular rotation of the 30S subunit head domain, bearing a single P/E state transfer RNA (tRNA). We identify five different binding sites for viomycin, four of which have not been previously described. To resolve the details of their binding interactions, we solved the 3.1-angstrom crystal structure of a viomycin-bound ribosome complex, revealing that all five viomycins bind to ribosomal RNA. One of these (Viol) corresponds to the single viomycin that was previously identified in a complex with a nonrotated classical -state ribosome. Three of the newly observed binding sites (Vio3, Vio4, and VioS) are clustered at intersubunit bridges, consistent with the ability of viomycin to inhibit subunit dissociation. We propose that one or more of these same three viomycins induce intersubunit rotation by selectively binding the rotated state of the ribosome at dynamic elements of 16S and 235 rRNA, thus, blocking conformational changes associated with molecular movements that are required for translocation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available