Chloramphenicol resistance mutation in Escherichia coli which maps in the major ribosomal protein gene cluster.
AUTOR(ES)
Baughman, G A
RESUMO
Localized mutagenesis and selection for streptomycin resistance were utilized to isolate a chloramphenicol resistance mutation in Escherichia coli K-12 linked to the strA (rpsL) locus. Bacteriophage P1 transduction verified the map position of the new resistance mutation at 72 min, placing it within a dense cluster of ribosomal protein genes. The map position differs from that of known cmlA and cmlB mutations, which map at 18 and 21 min, respectively. Ribosomes prepared from chloramphenicol-resistant and -sensitive isogenic transductants were analyzed in vitro for activity in formation of N-formylmethionyl-puromycin, polyphenylalanine, and polylysine in the presence of inhibitory concentrations of chloramphenicol. Comparisons were also made of 14C-chloramphenicol binding to 70S ribosomes and of the two-dimensional polyacrylamide gel electrophoresis pattern of ribosomal proteins from each strain. There was no detectable difference between ribosomes from sensitive and resistant strains as measured by these assays. Enzymatic modification by chloramphenicol acetyltransferase is not responsible for the observed phenotype.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=218315Documentos Relacionados
- Gene for the alpha subunit of Bacillus subtilis RNA polymerase maps in the ribosomal protein gene cluster.
- Patterns of polarity in the Escherichia coli car AB gene cluster.
- Cloning and sequence analysis of the Chlamydia trachomatis spc ribosomal protein gene cluster.
- Molecular cloning of the Escherichia coli B L-fucose-D-arabinose gene cluster.
- Characterization of an amber mutation in the structural gene for ribosomal protein L15, which impairs the expression of the protein export gene, secY, in Escherichia coli.
