Structural highlights
1qvg is a 12 chain structure with sequence from Haloarcula marismortui and Synthetic construct. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Method: | X-ray diffraction, Resolution 2.9Å |
| Ligands: | , , , , |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
RL2_HALMA One of the primary rRNA binding proteins. Required for association of the 30S and 50S subunits to form the 70S ribosome, for tRNA binding and peptide bond formation. It has been suggested to have peptidyltransferase activity; this is somewhat controversial. Makes several contacts with the 16S rRNA in the 70S ribosome (By similarity).[HAMAP-Rule:MF_01320_A]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
During translation, tRNAs cycle through three binding sites on the ribosome: the A, the P, and the E sites. We have determined the structures of complexes between the Haloarcula marismortui large ribosomal subunit and two different E site substrates: a deacylated tRNA acceptor stem minihelix and a CCA-acceptor end. Both of these tRNA mimics contain analogs of adenosine 76, the component responsible for a large proportion of E site binding affinity. They bind in the center of the loop-extension of protein L44e, and make specific contacts with both L44e and 23S rRNA including bases that are conserved in all three kingdoms of life. These contacts are consistent with the footprinting, protection, and cross-linking data that have identified the E site biochemically. These structures explain the specificity of the E site for deacylated tRNAs, as it is too small to accommodate any relevant aminoacyl-tRNA. The orientation of the minihelix suggests that it may mimic the P/E hybrid state. It appears that the E site on the 50S subunit was formed by only RNA in the last common ancestor of the three kingdoms, since the proteins at the E sites of H. marismortui and Deinucoccus radiodurans large subunits are not homologous.
Structures of deacylated tRNA mimics bound to the E site of the large ribosomal subunit.,Schmeing TM, Moore PB, Steitz TA RNA. 2003 Nov;9(11):1345-52. PMID:14561884[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Schmeing TM, Moore PB, Steitz TA. Structures of deacylated tRNA mimics bound to the E site of the large ribosomal subunit. RNA. 2003 Nov;9(11):1345-52. PMID:14561884
