1q81
From Proteopedia
Crystal Structure of minihelix with 3' puromycin bound to A-site of the 50S ribosomal subunit.
Structural highlights
FunctionRL2_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 ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe large ribosomal subunit catalyzes peptide bond formation and will do so by using small aminoacyl- and peptidyl-RNA fragments of tRNA. We have refined at 3-A resolution the structures of both A and P site substrate and product analogues, as well as an intermediate analogue, bound to the Haloarcula marismortui 50S ribosomal subunit. A P site substrate, CCA-Phe-caproic acid-biotin, binds equally to both sites, but in the presence of sparsomycin binds only to the P site. The CCA portions of these analogues are bound identically by either the A or P loop of the 23S rRNA. Combining the separate P and A site substrate complexes into one model reveals interactions that may occur when both are present simultaneously. The alpha-NH(2) group of an aminoacylated fragment in the A site forms one hydrogen bond with the N3 of A2486 (2451) and may form a second hydrogen bond either with the 2' OH of the A-76 ribose in the P site or with the 2' OH of A2486 (2451). These interactions position the alpha amino group adjacent to the carbonyl carbon of esterified P site substrate in an orientation suitable for a nucleophilic attack. Structural insights into peptide bond formation.,Hansen JL, Schmeing TM, Moore PB, Steitz TA Proc Natl Acad Sci U S A. 2002 Sep 3;99(18):11670-5. Epub 2002 Aug 16. PMID:12185246[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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