Format

Send to

Choose Destination
J Mol Biol. 1998 May 29;279(1):233-44.

Crystal structure of ribosomal protein S8 from Thermus thermophilus reveals a high degree of structural conservation of a specific RNA binding site.

Author information

1
Institute of Protein Research, Russian Academy of Sciences, Moscow Region, Russia.

Abstract

S8 is one of the core ribosomal proteins. It binds to 16 S RNA with high affinity and independently of other ribosomal proteins. It also acts as a translational repressor in Escherichia coli by binding to its own mRNA. The structure of Thermus thermophilus S8 has been determined by the method of multiple isomorphous replacement at 2.9 A resolution and refined to a crystallographic R-factor of 16.2% (Rfree 27.5%). The two domains of the structure have an alpha/beta fold and are connected by a long protruding loop. The two molecules in the asymmetric unit of the crystal interact through an extensive hydrophobic core and form a tightly associated dimer, while symmetry-related molecules form a joint beta-sheet of mixed type. This type of protein-protein interaction could be realized within the ribosomal assembly. A comparison of the structures of T. thermophilus and Bacillus stearothermophilus S8 shows that the interdomain loop is eight residues longer in the former and reveals high structural conservation of an extensive region, located in the C-terminal domain. From mutational studies this region was proposed earlier to be involved in specific interaction with RNA. On the basis of these data and on the comparison of the two structures of S8, it is proposed that the three-dimensional structure of specific RNA binding sites in ribosomal proteins is highly conserved among different species.

PMID:
9636713
DOI:
10.1006/jmbi.1998.1758
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center