Premium
Role of 16S ribosomal RNA methylations in translation initiation in Escherichia coli
Author(s) -
Das Gautam,
Thotala Dinesh Kumar,
Kapoor Suman,
Karunanithi Sheelarani,
Thakur Suman S,
Singh N Sadananda,
Varshney Umesh
Publication year - 2008
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1038/emboj.2008.20
Subject(s) - biology , library science , computer science
Translation initiation from the ribosomal P‐site is the specialty of the initiator tRNAs (tRNA fMet ). Presence of the three consecutive G‐C base pairs (G29‐C41, G30‐C40 and G31‐C39) in their anticodon stems, a highly conserved feature of the initiator tRNAs across the three kingdoms of life, has been implicated in their preferential binding to the P‐site. How this feature is exploited by ribosomes has remained unclear. Using a genetic screen, we have isolated an Escherichia coli strain, carrying a G122D mutation in folD , which allows initiation with the tRNA fMet containing mutations in one, two or all the three G‐C base pairs. The strain shows a severe deficiency of methionine and S ‐adenosylmethionine, and lacks nucleoside methylations in rRNA. Targeted mutations in the methyltransferase genes have revealed a connection between the rRNA modifications and the fundamental process of the initiator tRNA selection by the ribosome.