Alteration in location of a conserved GTPase-associated center of the ribosome induced by mutagenesis influences the structure of peptidyltransferase center and activity of elongation factor G.
Translocation catalyzed by elongation factor G occurs after the peptidyltransferase reaction on the large ribosomal subunit. Deacylated tRNA in the P-site stimulates multiple turnover GTPase activity of EF-G. We suggest that the allosteric signal from the peptidyltransferase center that activates EF-G may involve the alteration in the conformation of elongation factor binding center of the ribosome. The latter consists of the moveable GTPase-associated center and the sarcin-ricin loop that keeps its position on the ribosome during translation elongation. The position of the GTPase-associated center was altered by mutagenesis. An insertion of additional base pair at positions C1030/G1124 was lethal and affected function of EF-G, but not that of EF-Tu. Structure probing revealed a putative allosteric signal pathway connecting the P-site with the binding site of the elongation factors. The results are consistent with the different structural requirements for EF-G and EF-Tu function, where the integrity of the path between the peptidyltransferase center and both GTPase-associated center and sarcin-ricin loop is important for EF-G binding.
Sergiev
Petr V
PV
Department of Chemistry and A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119992, Russia.
Lesnyak
Dmitry V
DV
Burakovsky
Dmitry E
DE
Kiparisov
Sergey V
SV
Leonov
Andrei A
AA
Bogdanov
Alexey A
AA
Brimacombe
Richard
R
Dontsova
Olga A
OA
D001665:Binding Sites; D017124:Conserved Sequence; D034301:Deinococcus; D020558:GTP Phosphohydrolases / Q000737:chemistry / Q000378:metabolism*; D019614:Haloarcula marismortui; D009154:Mutation; D009690:Nucleic Acid Conformation; D020653:Peptide Elongation Factor G / Q000378:metabolism*; D010458:Peptidyl Transferases / Q000737:chemistry* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012338:RNA, Ribosomal, 23S / Q000235:genetics* / Q000502:physiology; D012343:RNA, Transfer / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000502:physiology*
D020653:Peptide Elongation Factor G; D012338:RNA, Ribosomal, 23S; D012343:RNA, Transfer; D010458:Peptidyl Transferases; D020558:GTP Phosphohydrolases