title: Translational regulation via L11: molecular switches on the ribosome turned on and off by thiostrepton and micrococcin.
abstract: The thiopeptide class of antibiotics targets the GTPase-associated center (GAC) of the ribosome to inhibit translation factor function. Using X-ray crystallography, we have determined the binding sites of thiostrepton (Thio), nosiheptide (Nosi), and micrococcin (Micro), on the Deinococcus radiodurans large ribosomal subunit. The thiopeptides, by binding within a cleft located between the ribosomal protein L11 and helices 43 and 44 of the 23S rRNA, overlap with the position of domain V of EF-G, thus explaining how this class of drugs perturbs translation factor binding to the ribosome. The presence of Micro leads to additional density for the C-terminal domain (CTD) of L7, adjacent to and interacting with L11. The results suggest that L11 acts as a molecular switch to control L7 binding and plays a pivotal role in positioning one L7-CTD monomer on the G' subdomain of EF-G to regulate EF-G turnover during protein synthesis.
authors.affiliation: Cluster of Excellence for Macromolecular Complexes, Institut für Organische Chemie und Chemische Biologie, J.W. Goethe-Universität Frankfurt am Main, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany.
authors.forename: Joerg M
authors.initials: JM
authors.lastname: Harms
authors.forename: Daniel N
authors.initials: DN
authors.lastname: Wilson
authors.forename: Frank
authors.initials: F
authors.lastname: Schluenzen
authors.forename: Sean R
authors.initials: SR
authors.lastname: Connell
authors.forename: Torsten
authors.initials: T
authors.lastname: Stachelhaus
authors.forename: Zaneta
authors.initials: Z
authors.lastname: Zaborowska
authors.forename: Christian M T
authors.initials: CM
authors.lastname: Spahn
authors.forename: Paola
authors.initials: P
authors.lastname: Fucini
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001430:Bacteriocins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D034301:Deinococcus / Q000737:chemistry / Q000378:metabolism; D005786:Gene Expression Regulation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D014176:Protein Biosynthesis; D017434:Protein Structure, Tertiary; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry / Q000378:metabolism; D013844:Thiazoles / Q000737:chemistry / Q000378:metabolism; D013883:Thiostrepton / Q000737:chemistry / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001430:Bacteriocins; D010455:Peptides; D012269:Ribosomal Proteins; D013844:Thiazoles; C027624:ribosomal protein L11; C009779:micrococcin; C014134:nosiheptide; D013883:Thiostrepton