ADP-ribosylated elongation factor 2 (ADP-ribosyl-EF-2) is unable to promote translocation within the ribosome.
Elongation factor 2 (EF-2), ADP-ribosylated in vitro by the A-fragment of diphtheria toxin, can (in the presence of GMPPCP) form stable complexes with ribosomes regardless of whether the ribosomes are empty or carrying poly(U) and Phe-tRNA in the A-site. Despite its efficient binding to ribosomes, ADP-ribosyl-EF-2, in contrast to the non-modified EF-2 is unable to promote the shift of Phe-tRNA from the A-site to the P-site of the ribosome as determined by the puromycin reaction, i.e. it is incapable of promoting the translocation reaction within the ribosome.
Davydova
E K
EK
Institute of Protein Research, Academy of Sciences of the USSR, Pushchino, Moscow Region.
Ovchinnikov
L P
LP
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D001692:Biological Transport; D004167:Diphtheria Toxin / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000378:metabolism*; D011072:Poly U / Q000378:metabolism; D011691:Puromycin / Q000378:metabolism; D012360:RNA, Transfer, Phe / Q000378:metabolism; D011817:Rabbits; D012270:Ribosomes / Q000378:metabolism*
D004167:Diphtheria Toxin; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D012360:RNA, Transfer, Phe; D000246:Adenosine Diphosphate Ribose; D011072:Poly U; C011265:guanosine 5'-(beta,gamma-methylene)triphosphate; D011691:Puromycin; D006160:Guanosine Triphosphate