Resistance to various tetracyclines mediated by transposon Tn10 in Escherichia coli K-12.
نویسندگان
چکیده
Levels of resistance to tetracycline, chlortetracycline, demethylchlortetracycline, doxycycline, oxytetracycline, methacycline, pyrrolidinotetracycline, minocycline, and beta-chelocardin of Escherichia coli K-12 carrying transposon Tn10 or defined DNA segments of Tn10 were determined. In all cases, tetA was the only gene required for resistance. Doxycycline was the most effective inducer of tetA gene expression.
منابع مشابه
Deletions generated by the transposon Tn10 in the srl recA region of the Escherichia coli K-12 chromosome.
A negative regulatory gene for the srl operon (srlR) was recognized by the characteristics of an insertion mutation generated by the transposon Tn10 determining tetracycline resistance. This finding is discussed in light of previous hypotheses on the regulation of the srl genes, which mediate metabolism of glucitol (i.e., sorbitol). Mapping showed that the order of genes in this region is: srlR...
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The mini-Tn10 transposon (delta 16 delta 17Tn10) confers tetracycline resistance. When inserted between a gene and its promoter, it blocks transcription and prevents expression of that gene. Tetracycline in the medium induces divergent transcription of the tetA and tetR genes within the transposon, and this transcription extends beyond the transposon in both directions into the bacterial genes....
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 27 5 شماره
صفحات -
تاریخ انتشار 1985