4ji3
Crystal Structure of 30S ribosomal subunit from Thermus thermophilusCrystal Structure of 30S ribosomal subunit from Thermus thermophilus
Structural highlights
FunctionRS13_THET8 Located at the top of the head of the 30S subunit, it contacts several helices of the 16S rRNA. In the 70S ribosome structure it contacts the 23S rRNA (bridge B1a) and protein L5 of the 50S subunit (bridge B1b), connecting the top of the two subunits; these bridges are in contact with the A site and P site tRNAs respectively and are implicated in movement during ribosome translocation. Separately contacts the tRNAs in the A and P sites.[HAMAP-Rule:MF_01315] Publication Abstract from PubMedThe ribosome decodes mRNA by monitoring the geometry of codon-anticodon base-pairing using a set of universally conserved 16S rRNA nucleotides within the conformationally dynamic decoding site. By applying single-molecule FRET and X-ray crystallography, we have determined that conditional-lethal, streptomycin-dependence mutations in ribosomal protein S12 interfere with tRNA selection by allowing conformational distortions of the decoding site that impair GTPase activation of EF-Tu during the tRNA selection process. Distortions in the decoding site are reversed by streptomycin or by a second-site suppressor mutation in 16S rRNA. These observations encourage a refinement of the current model for decoding, wherein ribosomal protein S12 and the decoding site collaborate to optimize codon recognition and substrate discrimination during the early stages of the tRNA selection process. The central role of protein S12 in organizing the structure of the decoding site of the ribosome.,Demirci H, Wang L, Murphy FV 4th, Murphy EL, Carr JF, Blanchard SC, Jogl G, Dahlberg AE, Gregory ST RNA. 2013 Oct 23. PMID:24152548[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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