| Title | Functional Analysis of the Invariant Residue G791 of Escherichia coli 16S rRNA |
|---|---|
| Author | Woo-Seok Song1, Hong-Man Kim1, Jae-Hong Kim2, Se-Hoon Sim1, Sang-Mi Ryou3, Sanggoo Kim3, Chang-Jun Cha4, Philip R. Cunningham5, Jeehyeon Bae2, and Kangseok Lee1* |
| Address | 1Department of Life Science, Chung-Ang University, Seoul 156-756, Republic of Korea, 2Graduate School of Life Science and Biotechnology, Pochon CHA University, Seongnam 463-836, Republic of Korea, 3Korea Basic Science Institute, Seoul 136-713, Republic of Korea, 4Department of Biotechnology and BET Institute, Chung-Ang University, Anseong 456-756, Republic of Korea, 5Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA |
| Bibliography | Journal of Microbiology, 45(5),418-421, 2007, |
| DOI | |
| Key Words | specialized ribosome, rRNA, subunit association, G791, protein synthesis |
| Abstract | The nucleotide at position 791(G791) of E. coli 16S rRNA was previously identified as an invariant residue for ribosomal function. In order to characterize the functional role of G791, base substitutions were introduced at this position, and mutant ribosomes were analyzed with regard to their protein synthesis ability, via the use of a specialized ribosome system. These ribosomal RNA mutations attenuated the ability of ribosomes to conduct protein synthesis by more than 65%. A transition mutation (G to A) exerted a moderate effect on ribosomal function, whereas a transversion mutation (G to C or U) resulted in a loss of protein synthesis ability of more than 90%. The sucrose gradient profiles of ribosomes and primer extension analysis showed that the loss of protein-synthesis ability of mutant ribosomes harboring a base substitution from G to U at position 791 stems partially from its inability to form 70S ribosomes. These findings show the involvement of the nucleotide at position 791 in the association of ribosomal subunits and protein synthesis steps after 70S formation, as well as the possibility of using 16S rRNA mutated at position 791 for the selection of second-site revertants in order to identify ligands that interact with G791 in protein synthesis. |
| Download PDF | 45(5)_07.pdf |