Impact of methylations of m2G966/m5C967 in 16S rRNA on bacterial fitness and translation initiation.
The functional centers of the ribosome in all organisms contain ribosomal RNA (rRNA) modifications, which are introduced by specialized enzymes and come at an energy cost for the cell. Surprisingly, none of the modifications tested so far was essential for growth and hence the functional role of modifications is largely unknown. Here, we show that the methyl groups of nucleosides m(2)G966 and m(5)C967 of 16S rRNA in Escherichia coli are important for bacterial fitness. In vitro analysis of all phases of translation suggests that the m(2)G966/m(5)C967 modifications are dispensable for elongation, termination and ribosome recycling. Rather, the modifications modulate the early stages of initiation by stabilizing the binding of fMet-tRNA(fMet) to the 30S pre-initiation complex prior to start-codon recognition. We propose that the m(2)G966 and m(5)C967 modifications help shaping the bacterial proteome, most likely by fine-tuning the rates that determine the fate of a given messenger RNA (mRNA) at early checkpoints of mRNA selection.
Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
Dmitry E
DE
Burakovsky
Irina V
IV
Prokhorova
Petr V
PV
Sergiev
Pohl
P
Milón
Olga V
OV
Sergeeva
Alexey A
AA
Bogdanov
Marina V
MV
Rodnina
Olga A
OA
Dontsova
D003080:Cold Temperature; D019175:DNA Methylation; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D056084:Genetic Fitness; D010441:Peptide Chain Elongation, Translational; D010442:Peptide Chain Initiation, Translational; D010443:Peptide Chain Termination, Translational; D012336:RNA, Ribosomal, 16S / Q000737:chemistry* / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism
D012336:RNA, Ribosomal, 16S