PMID:14966659

From EcoliWiki
Jump to navigation Jump to search
Citation

Hosaka, T, Tamehiro, N, Chumpolkulwong, N, Hori-Takemoto, C, Shirouzu, M, Yokoyama, S and Ochi, K (2004) The novel mutation K87E in ribosomal protein S12 enhances protein synthesis activity during the late growth phase in Escherichia coli. Mol. Genet. Genomics 271:317-24

Abstract

Resistance to streptomycin in bacterial cells often results from a mutation in the rpsL gene that encodes the ribosomal protein S12. We found that a particular rpsL mutation (K87E), newly identified in Escherichia coli, causes aberrant protein synthesis activity late in the growth phase. While protein synthesis decreased with age in cells in the wild-type strain, it was sustained at a high level in the mutant, as determined using living cells. This was confirmed using an in vitro protein synthesis system with poly(U) and natural mRNAs (GFP mRNA and CAT mRNA). Other classical rpsL mutations (K42N and K42T) tested did not show such an effect, indicating that this novel characteristic is typical of ribosomes bearing the K87E mutant form of S12, although the K87E mutation conferred the streptomycin resistance and error-restrictive phenotypes also seen with the K42N and K42T mutations. The K87E (but not K42N or K42T) mutant ribosomes exhibited increased stability of the 70S complex in the presence of low concentrations of magnesium. We propose that the aberrant activation of protein synthesis at the late growth phase is caused by the increased stability of the ribosome.

Links

PubMed Online version:10.1007/s00438-004-0982-z

Keywords

Chloramphenicol O-Acetyltransferase/genetics; Chloramphenicol O-Acetyltransferase/metabolism; Drug Resistance, Microbial; Escherichia coli/genetics; Escherichia coli/growth & development; Escherichia coli/metabolism; Gene Expression Regulation, Bacterial/drug effects; Green Fluorescent Proteins; Luminescent Proteins/genetics; Luminescent Proteins/metabolism; Magnesium/pharmacology; Molecular Sequence Data; Mutagenesis, Site-Directed; Mutation/genetics; Poly U; RNA, Messenger/genetics; RNA, Messenger/metabolism; Ribosomal Proteins/genetics; Ribosomal Proteins/metabolism; Ribosomes/drug effects; Ribosomes/metabolism; Streptomycin/pharmacology

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.