Characterization of the generimK responsible for the addition of glutamic acid residues to the C-terminus of ribosomal protein S6 inEscherichia coli K12
- 167 Downloads
Ribosomal protein S6 of wild-type strains ofEscherichia coli contains up to six glutamic acid residues at its C-terminus. The first two residues are encoded by the structural gene for this protein (rpsF) and the rest are added post-translationally. Mutants deficient in this modification were isolated and characterized genetically and biochemically. The S6 protein in these mutants appeared to contain only two glutamic acid residues at the C-terminus as expected. The mutated gene was termedrimK and was mapped at 18.7 min betweencmlA andaroA. TherimK gene was cloned into a cosmid vector and its nucleotide sequence determined. Analysis of the transcriptional and translational products of this gene indicates that it encodes a protein with an Mr of 31.5 kDa and that it forms an operon with a gene encoding a 24 kDa protein. AnrpsF mutant containing a Glu to Lys replacement in the second residue from the C-terminus of protein S6 was isolated. The S6 protein of this mutant was apparently inaccessible to the RimK modification system. This indicates that the RimK modification system requires the wild-type amino acid sequence at least in the C-terminal region of ribosomal protein S6.
Key wordsEscherichia coli Ribosomal protein S6 Addition of glutamic acid residues Cloning and sequencing
Unable to display preview. Download preview PDF.
- Bachmann BJ (1987) Linkage map ofEscherichia coli K-12, Edition 7. In: Neidhart FC, Ingraham JL, Low KB, Magasanik B, Schaechter M, Umbarger HE (eds)Escherichia coli andSalmonella typhimurium, cellular and molecular Biology, vol. 2. American Society for Microbiology, Washington DC, pp 807–876Google Scholar
- Dekio S (1971) Genetic studies of the ribosomal proteins inEscherichia coli. VII. Mapping of several ribosomal protein components by transduction experiments betweenShigella dysenteriae andEscherichia coli, and between different strains ofEscherichia coli. Mol Gen Genet 113:20–30PubMedGoogle Scholar
- Tanaka S, Matsushita Y, Yoshikawa A, Isono K (1989) Cloning and molecular characterization of the generimL which encodes an enzyme acetylating ribosomal protein L12 ofEscherichia coli K12. Mol Gen Genet, in pressGoogle Scholar