Description
The tetracycline repressor (TetR) is a transcriptional regulator which normally binds tightly to its palindromic tetO operator DNA, blocking gene expression. Tet causes the repressor to dissociate from the DNA, allowing transcription to occur. A novel reverse TetR (revTetR) requires tetracycline as a co-
repressor to bind tetO and block transcription. Anhydrotetracycline (hydrochloride) is a powerful effector in both the tetracycline repressor (TetR) and reverse TetR (revTetR) systems, binding the Tet repressor 35-
fold more strongly than Tet. Moreover, anhydrotetracycline poorly binds the 30S ribosomal subunit, compared to Tet, so it does not act as a general inhibitor of translation and is a poor antibiotic. Perhaps related to this, the concentration of anhydrotetracycline that inhibits eukaryotic cell growth is more than a 1,000-
fold above the dose that alters transcription through TetR.
Uses
Anhydrotetracycline is a degradation product of tetracycline, formed by dehydration at the C6 position under acidic conditions to aromatise the B ring. Anhydrotetracycline is an important standard for monitoring tetracycline stability. Although the degradation is associated with a loss of antibiotic activity, anhydrotetracycline is considered biologically active and is thought responsible for aspects of tetracycline toxicity.
Uses
Anhydrotetracycline hydrochloride is a salt of a degradation product of tetracycline, formed by dehydration at the C6 position under acidic conditions to aromatise the B ring. Anhydrotetracycline is an important standard for monitoring tetracycline stability. Although the degradation is associated with a loss of antibiotic activity, anhydrotetracycline is considered biologically active and is thought responsible for aspects of tetracycline toxicity.
