Overproduction of transposon Tn10-encoded tetracycline resistance protein results in cell death and loss of membrane potential.
نویسندگان
چکیده
High-level expression of the Tn10 tetracycline resistance protein TetA in Escherichia coli caused partial collapse of the membrane potential, arrest of growth, and killing of the cells. Since alpha-methylglucoside transport was not affected, the overproduced TetA protein may cause not destruction of membrane structure but rather unrestricted translocation of protons and/or ions across the membrane.
منابع مشابه
Reduced expression of Tn 10-mediated tetracycline resistance in Escherichia coli containing more than one copy of the transposon.
In Escherichia coli a single copy of Tn10 confers high-level resistance to tetracycline. Resistance itself results from expression of three distinct mechanisms which normally act together (Shales et al., 1980). In cells containing two copies of Tn10, the level of resistance to tetracycline was reduced. This was not due to overproduction of the repressor which controls the resistance genes, beca...
متن کاملTransport of divalent cations with tetracycline as mediated by the transposon Tn10-encoded tetracycline resistance protein.
Tetracycline uptake into inverted membrane vesicles from Tn10-bearing Escherichia coli cells required divalent cations. The degree of the stimulation of tetracycline uptake by various divalent cations showed the following decreasing order: Co2+ greater than Mn2+ greater than Mg2+ greater than Cd2+ greater than Ca2+. This order is consistent with the increasing order of the dissociation constant...
متن کاملMultidrug resistance pump AcrAB-TolC is required for high-level, Tet(A)-mediated tetracycline resistance in Escherichia coli.
OBJECTIVES Starting from the observation that Escherichia coli tolC mutations severely reduced the high-level resistance to tetracycline afforded by Tn10- and plasmid-encoded Tet(A) pumps, we studied the mechanism of this susceptibility. METHODS The MIC of tetracycline for MC4100 tolC::Tn10 and several tolC mutants carrying the Tn10 in other sites on the chromosome (thr::Tn10) was determined....
متن کاملResistance to various tetracyclines mediated by transposon Tn10 in Escherichia coli K-12.
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 tet...
متن کاملGenetic evidence that Tn10 transposes by a nonreplicative mechanism.
We present genetic evidence that the tetracycline resistance element Tn10 transposes by a nonreplicative mechanism. Heteroduplex Tn10 elements containing three single base pair mismatches were constructed on lambda phage genomes and allowed to transpose from lambda into the bacterial chromosome. Analysis of TetR colonies resulting from such transpositions suggests that information from both str...
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عنوان ژورنال:
- Journal of bacteriology
دوره 171 6 شماره
صفحات -
تاریخ انتشار 1989