de.mpg.escidoc.pubman.appbase.FacesBean
Deutsch
 
Hilfe Wegweiser Impressum Kontakt Einloggen
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Deacylated tRNA is released from the E site upon A site occupation but before GTP is hydrolyzed by EF-Tu

MPG-Autoren

Dinos,  George
Max Planck Society;

http://pubman.mpdl.mpg.de/cone/persons/resource/persons50642

Wilson,  Daniel N.
Dept. of Vertebrate Genomics (Head: Hans Lehrach), Max Planck Institute for Molecular Genetics, Max Planck Society;

http://pubman.mpdl.mpg.de/cone/persons/resource/persons50444

Nierhaus,  Knud H.
Ribosomes, Max Planck Institute for Molecular Genetics, Max Planck Society;

Externe Ressourcen
Es sind keine Externen Ressourcen verfügbar
Volltexte (frei zugänglich)
Es sind keine frei zugänglichen Volltexte verfügbar
Ergänzendes Material (frei zugänglich)
Es sind keine frei zugänglichen Ergänzenden Materialien verfügbar
Zitation

Dinos, G., Kalpaxis, D. L., Wilson, D. N., & Nierhaus, K. H. (2005). Deacylated tRNA is released from the E site upon A site occupation but before GTP is hydrolyzed by EF-Tu. Nucleic Acids Research (London), 33(16), 5291-5296. doi:10.1093/nar/gki833.


Zitierlink: http://hdl.handle.net/11858/00-001M-0000-0010-858F-9
Zusammenfassung
The presence or absence of deacylated tRNA at the E site sharply influences the activation energy required for binding of a ternary complex to the ribosomal A site indicating the different conformations that the E-tRNA imparts on the ribosome. Here we address two questions: (i) whether or not peptidyltransferase—the essential catalytic activity of the large ribosomal subunit—also depends on the occupancy state of the E site and (ii) at what stage the E-tRNA is released during an elongation cycle. Kinetics of the puromycin reaction on various functional states of the ribosome indicate that the A-site substrate of the peptidyltransferase center, puromycin, requires the same activation energy for peptide-bond formation under all conditions tested. We further demonstrate that deacylated tRNA is released from the E site by binding a ternary complex aminoacyl-tRNA•EF-Tu•GDPNP to the A site. This observation indicates that the E-tRNA is released after the decoding step but before both GTP hydrolysis by EF-Tu and accommodation of the A-tRNA. Collectively these results reveal that the reciprocal linkage between the E and A sites affects the decoding center on the 30S subunit, but does not influence the rate of peptide-bond formation at the active center of the 50S subunit.