title: Mapping of the second tetracycline binding site on the ribosomal small subunit of E.coli.
abstract: Tetracycline blocks stable binding of aminoacyl-tRNA to the bacterial ribosomal A-site. Various tetracycline binding sites have been identified in crystals of the 30S ribosomal small subunit of Thermus thermophilus. Here we describe a direct photo- affinity modification of the ribosomal small subunits of Escherichia coli with 7-[3H]-tetracycline. To select for specific interactions, an excess of the 30S subunits over tetracycline has been used. Primer extension analysis of the 16S rRNA revealed two sites of the modifications: C936 and C948. Considering available data on tetracycline interactions with the prokaryotic 30S subunits, including the presented data (E.coli), X-ray data (T.thermophilus) and genetic data (Helicobacter pylori, E.coli), a second high affinity tetracycline binding site is proposed within the 3'-major domain of the 16S rRNA, in addition to the A-site related tetracycline binding site.
authors.affiliation: Department of Chemistry, Moscow State University, 119992 Moscow, Russian Federation.
authors.forename: Maria M
authors.initials: MM
authors.lastname: Anokhina
authors.forename: Andrea
authors.initials: A
authors.lastname: Barta
authors.forename: Knud H
authors.initials: KH
authors.lastname: Nierhaus
authors.forename: Vera A
authors.initials: VA
authors.lastname: Spiridonova
authors.forename: Alexei M
authors.initials: AM
authors.lastname: Kopylov
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D011500:Protein Synthesis Inhibitors / Q000737:chemistry / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry / Q000378:metabolism*; D013752:Tetracycline / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D011500:Protein Synthesis Inhibitors; D012336:RNA, Ribosomal, 16S; D013752:Tetracycline