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Ribosomal protein L2 is involved in the association of the ribosomal subunits, tRNA binding to A and P sites and peptidyl transfer
Author(s) -
Diedrich Gundo,
Spahn Christian M. T.,
Stelzl Ulrich,
Schäfer Markus A.,
Wooten Tammy,
Bochkariov Dmitry E.,
Cooperman Barry S.,
Traut Robert R.,
Nierhaus Knud H.
Publication year - 2000
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1093/emboj/19.19.5241
Subject(s) - peptidyl transferase , 50s , biology , transfer rna , ribosome , 23s ribosomal rna , ribosomal rna , ribosomal protein , protein subunit , p site , biochemistry , peptide , 30s , peptide bond , rna , genetics , gene
Ribosomal proteins L2, L3 and L4, together with the 23S RNA, are the main candidates for catalyzing peptide bond formation on the 50S subunit. That L2 is evolutionarily highly conserved led us to perform a thorough functional analysis with reconstituted 50S particles either lacking L2 or harboring a mutated L2. L2 does not play a dominant role in the assembly of the 50S subunit or in the fixation of the 3′‐ends of the tRNAs at the peptidyl‐transferase center. However, it is absolutely required for the association of 30S and 50S subunits and is strongly involved in tRNA binding to both A and P sites, possibly at the elbow region of the tRNAs. Furthermore, while the conserved histidyl residue 229 is extremely important for peptidyl‐transferase activity, it is apparently not involved in other measured functions. None of the other mutagenized amino acids (H14, D83, S177, D228, H231) showed this strong and exclusive participation in peptide bond formation. These results are used to examine critically the proposed direct involvement of His229 in catalysis of peptide synthesis.