Transcriptional attenuation control of the tylosin-resistance gene tlrA in Streptomyces fradiae.
The tylosin producer Streptomyces fradiae contains four known resistance genes, two of which (tlrA and tlrD) encode methyltransferases that act on ribosomal RNA at a common site. Expression of tlrA is regulated via transcriptional attenuation. A short transcript, only 411 nucleotides long, terminates 27 nucleotides into the methylase-coding sequence in the uninduced state. Induction of tlrA is proposed to involve a ribosome-mediated conformational change within the mRNA leader that allows transcription to continue beyond the attenuation site, resulting in a transcript about 1450 nucleotides long. Transplantation of tlrD and/or tlrA into Streptomyces albus revealed that the induction specificity of tlrA depends upon the state of the ribosomes and is significantly altered in strains also expressing tlrD.
Kelemen
G H
GH
Department of Biochemistry, University of Leicester, UK.
Zalacain
M
M
Culebras
E
E
Seno
E T
ET
Cundliffe
E
E
D001483:Base Sequence; D001665:Binding Sites; D002240:Carbohydrate Sequence; D002874:Chromosome Mapping; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004352:Drug Resistance, Microbial / Q000235:genetics; D005798:Genes, Bacterial; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism; D013302:Streptomyces / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D015645:Tylosin / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*
D017931:DNA Primers; D004269:DNA, Bacterial; D012329:RNA, Bacterial; D012333:RNA, Messenger; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase; D015645:Tylosin