title: Targeting exposed RNA regions in crystals of the small ribosomal subunits at medium resolution.
abstract: Within the framework of ribosomal crystallography, the small subunits are being analyzed, using crystals diffracting to 3 A resolution. The medium resolution electron density map of this subunit, obtained by multiple isomorphous replacement, show recognizable morphologies, strikingly similar to the functional active conformer of the small ribosomal subunit. It contains elongated dense features, traceable as RNA chains as well as globular regions into which the structures determined for isolated ribosomal proteins, or other known structural motifs were fitted. To facilitate unbiased map interpretation, metal clusters are being covalently attached either to the surface of the subunits or to DNA oligomers complementary to exposed ribosomal RNA. Two surface cysteines and the 3' end of the 16S ribosomal RNA have been localized. Targeting several additional RNA regions shed light on their relative exposure and confirmed previous studies concerning their functional relevance.
authors.affiliation: Department of Structural Biology, Weizmann Institute, Rehovot, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Bartels
authors.forename: M
authors.initials: M
authors.lastname: Gluehmann
authors.forename: D
authors.initials: D
authors.lastname: Janell
authors.forename: F
authors.initials: F
authors.lastname: Schluenzen
authors.forename: A
authors.initials: A
authors.lastname: Tocilj
authors.forename: A
authors.initials: A
authors.lastname: Bashan
authors.forename: I
authors.initials: I
authors.lastname: Levin
authors.forename: H A
authors.initials: HA
authors.lastname: Hansen
authors.forename: J
authors.initials: J
authors.lastname: Harms
authors.forename: M
authors.initials: M
authors.lastname: Kessler
authors.forename: M
authors.initials: M
authors.lastname: Pioletti
authors.forename: T
authors.initials: T
authors.lastname: Auerbach
authors.forename: I
authors.initials: I
authors.lastname: Agmon
authors.forename: H
authors.initials: H
authors.lastname: Avila
authors.forename: M
authors.initials: M
authors.lastname: Simitsopoulou
authors.forename: S
authors.initials: S
authors.lastname: Weinstein
authors.forename: M
authors.initials: M
authors.lastname: Peretz
authors.forename: W S
authors.initials: WS
authors.lastname: Bennett
authors.forename: F
authors.initials: F
authors.lastname: Franceschi
authors.forename: A
authors.initials: A
authors.lastname: Yonath
mesh_terms: D018360:Crystallography, X-Ray; D003545:Cysteine / Q000737:chemistry; D018076:DNA, Complementary / Q000737:chemistry; D046911:Macromolecular Substances; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D012329:RNA, Bacterial / Q000737:chemistry; D012335:RNA, Ribosomal / Q000737:chemistry*; D012336:RNA, Ribosomal, 16S / Q000737:chemistry; D012269:Ribosomal Proteins / Q000737:chemistry; D012270:Ribosomes / Q000737:chemistry*; D055672:Static Electricity; D016963:Thermus thermophilus / Q000737:chemistry
chemical_list: D018076:DNA, Complementary; D046911:Macromolecular Substances; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012269:Ribosomal Proteins; D003545:Cysteine