Format

Send to

Choose Destination
Nucleic Acids Res. 2015 Jan;43(1):661-73. doi: 10.1093/nar/gku1314. Epub 2014 Dec 15.

Structural basis for the interaction of protein S1 with the Escherichia coli ribosome.

Author information

1
Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, Centre for Molecular Biology, University of Vienna, Dr. Bohrgasse 9/4, 1030 Vienna, Austria.
2
Department of Structural and Computational Biology, Max F. Perutz Laboratories, Centre for Molecular Biology, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria.
3
Gene Center, Department of Biochemistry and Center for integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany.
4
Department of Structural and Computational Biology, Max F. Perutz Laboratories, Centre for Molecular Biology, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, 1000 Ljubljana, Slovenia.
5
Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, Centre for Molecular Biology, University of Vienna, Dr. Bohrgasse 9/4, 1030 Vienna, Austria Isabella.Moll@univie.ac.at.

Abstract

In Gram-negative bacteria, the multi-domain protein S1 is essential for translation initiation, as it recruits the mRNA and facilitates its localization in the decoding centre. In sharp contrast to its functional importance, S1 is still lacking from the high-resolution structures available for Escherichia coli and Thermus thermophilus ribosomes and thus the molecular mechanism governing the S1-ribosome interaction has still remained elusive. Here, we present the structure of the N-terminal S1 domain D1 when bound to the ribosome at atomic resolution by using a combination of NMR, X-ray crystallography and cryo-electron microscopy. Together with biochemical assays, the structure reveals that S1 is anchored to the ribosome primarily via a stabilizing π-stacking interaction within the short but conserved N-terminal segment that is flexibly connected to domain D1. This interaction is further stabilized by salt bridges involving the zinc binding pocket of protein S2. Overall, this work provides one hitherto enigmatic piece in the 'ribosome puzzle', namely the detailed molecular insight into the topology of the S1-ribosome interface. Moreover, our data suggest novel mechanisms that have the potential to modulate protein synthesis in response to environmental cues by changing the affinity of S1 for the ribosome.

PMID:
25510494
PMCID:
PMC4288201
DOI:
10.1093/nar/gku1314
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center