Download MendeleyThe structure of the archaebacterial ribosomal protein S7 and its possible interaction with 16S rRNA.
Hosaka, H., Yao, M., Kimura, M., Tanaka, I.(2001) J Biochem 130: 695-701
- PubMed: 11686933
- DOI: https://doi.org/10.1093/oxfordjournals.jbchem.a003036
- Primary Citation of Related Structures:
1IQV - PubMed Abstract:
Ribosomal protein S7 is one of the ubiquitous components of the small subunit of the ribosome. It is a 16S rRNA-binding protein positioned close to the exit of the tRNA, and it plays a role in initiating assembly of the head of the 30S subunit. Previous structural analyses of eubacterial S7 have shown that it has a stable alpha-helix core and a flexible beta-arm. Unlike these eubacterial proteins, archaebacterial or eukaryotic S7 has an N-terminal extension of approximately 60 residues. The crystal structure of S7 from archaebacterium Pyrococcus horikoshii (PhoS7) has been determined at 2.1 A resolution. The final model of PhoS7 consists of six major alpha-helices, a short 3(10)-helix and two beta-stands. The major part (residues 18-45) of the N-terminal extension of PhoS7 reinforces the alpha-helical core by well-extended hydrophobic interactions, while the other part (residues 46-63) is not visible in the crystal and is possibly fixed only by interacting with 16S rRNA. These differences in the N-terminal extension as well as in the insertion (between alpha1 and alpha2) of the archaebacterial S7 structure from eubacterial S7 are such that they do not necessitate a major change in the structure of the currently available eubacterial 16S rRNA. Some of the inserted chains might pass through gaps formed by helices of the 16S rRNA.
Organizational Affiliation:
Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
