The signal transducer (BlaRI) and the repressor (BlaI) of the Staphylococcus aureus beta-lactamase operon are inducible.
The precise start points for transcription of the blaZ and of the blaRI/blaI genes of the Staphylococcus aureus beta-lactamase operon have been determined by primer extension analysis. Consequently the overlapping promoter sequences were deduced. Northern blots showed that the synthesis of the 2100 nt mRNA from blaRI is inducible and that a blaI probe hybridized to the same mRNA as the blaRI probe. The gene cat, encoding chloramphenicol acetyltransferase, was fused separately to the blaZ and blaRI/blaI promoters, and used to compare their strengths. The promoter for blaZ is about six times stronger than that for blaRI/blaI and the synthesis of chloramphenicol acetyltransferase from both promoters is inducible, supporting the results from the Northern blots.
Microbiology Unit, Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK1.
Simon R
SR
Clarke
Microbiology Unit, Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK1.
Keith G H
KGH
Dyke
D015152:Blotting, Northern; D015500:Chloramphenicol O-Acetyltransferase / Q000378:metabolism; D017930:Genes, Reporter; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D015183:Restriction Mapping; D015398:Signal Transduction; D013211:Staphylococcus aureus / Q000235:genetics* / Q000378:metabolism; D001618:beta-Lactamases / Q000096:biosynthesis / Q000235:genetics*
D012329:RNA, Bacterial; D012333:RNA, Messenger; D012097:Repressor Proteins; D015500:Chloramphenicol O-Acetyltransferase; D001618:beta-Lactamases