Tandemly activated tRNAs as participants in protein synthesis.
While all studies of protein synthesis to date have employed monoaminoacylated transfer RNAs, there have been reports that bisphenylalanyl-tRNA is formed by Thermus thermophilus phenylalanyl-tRNA synthetase. Such tandemly activated tRNAs have now been prepared by chemicoenzymatic techniques and are shown to function in both prokaryotic and mammalian protein synthesizing systems. They exhibit characteristics consistent with their possible utility under extreme conditions in natural systems and have important potential advantages for protein elaboration in cell free systems. Mechanistically, the bisaminoacylated tRNAs bind to the ribosomal A-site and utilize the aminoacyl moiety attached to the 3'-position of the terminal adenosine for addition to the growing polypeptide chain. Following translocation to the P-site and transfer of the formed peptidyl moiety, the donor tRNA dissociates from the ribosome as a monoaminoacylated tRNA capable of functioning in a subsequent polypeptide elongation step.
Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
Bixun
B
Wang
Jia
J
Zhou
Michiel
M
Lodder
Raymond D
RD
Anderson
Sidney M
SM
Hecht
D000818:Animals; D003062:Codon; D004926:Escherichia coli / Q000378:metabolism; D008956:Models, Chemical; D010445:Peptide Elongation Factors / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D014176:Protein Biosynthesis; D021381:Protein Transport; D012343:RNA, Transfer / Q000737:chemistry*; D011817:Rabbits; D012270:Ribosomes / Q000378:metabolism
D003062:Codon; D010445:Peptide Elongation Factors; D010455:Peptides; D012343:RNA, Transfer