Identification of repressor binding sites controlling expression of tetracycline resistance encoded by Tn10.

نویسندگان

  • L V Wray
  • W S Reznikoff
چکیده

The regulatory region controlling the expression of tetracycline resistance and repressor genes contains two nearly identical regions of dyad symmetry. Deletions of this control region were isolated by digestion with S1 nuclease. The ability of these deletions to bind the tet repressor was determined by an in vivo repressor titration assay. The results indicate that repressor specifically binds both regions of dyad symmetry.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effects of carriage and expression of the Tn10 tetracycline-resistance operon on the fitness of Escherichia coli K12.

We have been examining the consequences of alternative modes of regulation of plasmid-borne, Tn10-encoded tetracycline resistance for the fitness of Escherichia coli. In a tetracycline-free environment, we measured the effects on fitness that were caused by (1) maximally induced expression of the resistance operon, (2) low-level constitutive expression of the resistance protein, (3) residual ex...

متن کامل

Overlapping divergent promoters control expression of Tn10 tetracycline resistance.

We have previously examined the genetic organization and regulation of the Tn10 tetracycline-resistance determinant in Escherichia coli K-12. The structural genes for tetA, the Tn10 tetracycline-resistance function, and for tetR, the Tn10 tet repressor, are transcribed in opposite directions from promoters in a regulatory region located between the two structural genes. Expression of both tetA ...

متن کامل

Multidrug 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 کامل

Purification of the TET repressor and TET operator from the transposon Tn10 and characterization of their interaction.

The TET repressor for the TnlO-encoded tetracycline resistance gene has been purified to near-homogeneity. The TET repressor binds ['Hltetracycline with an apparent association constant greater than lo7 litersmol-'. The formation of the TET repressor * tetracycline complex is optimal between pH 7.5 and pH 12 and is reduced below pH 7.5. At pH 5.0, the TET repressor is inactive. The thermal stab...

متن کامل

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 کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Journal of bacteriology

دوره 156 3  شماره 

صفحات  -

تاریخ انتشار 1983