Premium
How can elongation factors EF‐G and EF‐Tu discriminate the functional state of the ribosome using the same binding site?
Author(s) -
Sergiev Petr V.,
Bogdanov Alexey A.,
Dontsova Olga A.
Publication year - 2005
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2005.09.010
Subject(s) - ef tu , ribosome , elongation factor , ricin , gtpase , gtp' , biophysics , binding site , helix (gastropod) , binding domain , a site , chemistry , microbiology and biotechnology , biology , biochemistry , rna , enzyme , ecology , snail , toxin , gene
Elongation factors EF‐G and EF‐Tu are structural homologues and share near‐identical binding sites on the ribosome, which encompass the GTPase‐associated centre (GAC) and the sarcin‐ricin loop (SRL). The SRL is fixed structure in the ribosome and contacts elongation factors in the vicinity of their GTP‐binding site. In contrast, the GAC is mobile and we hypothesize that it interacts with the alpha helix D of the EF‐Tu G‐domain in the same way as with the alpha helix A of the G′‐domain of EF‐G. The mutual locations of these helices and GTP‐binding sites in the structures of EF‐Tu and EF‐G are different. Thus, the orientation of the GAC relative to the SRL determines whether EF‐G or EF‐Tu will bind to the ribosome.