A flavoprotein (FAD). This bacterial enzyme confers resistance to all clinically relevant tetracyclines when expressed under aerobic conditions. The hydroxylated products are very unstable and lead to intramolecular cyclization and non-enzymic breakdown to undefined products.
Specify your search results
The enzyme appears in viruses and cellular organisms
BN1088_100004, tetracycline resistance protein from transposon Tn4351/Tn4400, tetracylcine resistance protein TetX, TetX, TetX family tetracycline inactivation enzyme, TetX2, more
tetracycline substrates, initial monohydroxylation at position 11a followed by intramolecular cyclization and non-enzymatic breakdown to undefined products
A flavoprotein (FAD). This bacterial enzyme confers resistance to all clinically relevant tetracyclines when expressed under aerobic conditions. The hydroxylated products are very unstable and lead to intramolecular cyclization and non-enzymic breakdown to undefined products.
tetracycline substrates, initial monohydroxylation at position 11a followed by intramolecular cyclization and non-enzymatic breakdown to undefined products
the enzyme shows a broad tetracycline antibiotic spectrum and a requirement for molecular oxygen and NADPH in antibiotic degradation. The tetracycline products are unstable at neutral pH, but mass spectral and NMR characterization under acidic conditions support initial monohydroxylation at position 11a followed by intramolecular cyclization and non-enzymatic breakdown to other undefined products
the enzyme shows a broad tetracycline antibiotic spectrum and a requirement for molecular oxygen and NADPH in antibiotic degradation. The tetracycline products are unstable at neutral pH, but mass spectral and NMR characterization under acidic conditions support initial monohydroxylation at position 11a followed by intramolecular cyclization and non-enzymatic breakdown to other undefined products
tigecycline is a substrate for TetX and bacterial strains containing the TetX gene are resistant to tigecycline due to the modification of tigecycline by TetX to form 11a-hydroxytigecycline, which has a weakened ability to inhibit protein translation compared with tigecycline. 11a-Hydroxytigecycline forms a weaker complex with magnesium than tigecycline, magnesium coordination is critical for binding tetracycline to the ribosome
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CRYSTALLIZATION/commentary
ORGANISM
UNIPROT
LITERATURE
in complex with tetracyclines minocycline and tigecycline at 2.18 and 2.30 A resolution, respectively. Both tetracyclines bind in a large tunnel-shaped active site in close contact to the cofactor FAD, preoriented for regioselective hydroxylation to 11alpha-hydroxytetracyclines. The bulky 9-tert-butylglycylamido substituent of tigecycline is solvent-exposed and does not interfere with TetX binding. In the TetX-minocycline complex a second binding site for a minocycline dimer is observed close to the active-site entrance. The putative dioxygen-binding cavities are located in the substrate-binding domain next to the active site
structure determinations at 2.1 A resolution of native TetX and its complexes with tetracyclines. Domain 1 exhibits the Rossmann fold responsible for binding of the coenzyme FAD through its adenosine monophosphate component, which is linked to the flavin mononucleotide containing the catalytically active isoalloxazine moiety. The second domain with an extended 7-stranded beta-sheet is positioned like a shield on top of the flavin-binding domain covered by five alpha-helices and is responsible for substrate recognition. A long C-terminal alpha-helix stabilizes the association of the two domains
construction of a sensitive fluorescent reporter system to detect and characterize the activity of enzymes that act upon the antibiotic, tetracycline and its derivatives. In this system, expression of the lux operon is regulated by the tetracycline repressor, TetR, which is expressed from the same plasmid under the control of an arabinose-inducible promoter. Addition of very low concentrations of tetracycline derivatives, well below growth inhibitory concentrations, result in luminescence production. Introduction of a plasmid expressing TetX, a tetracycline-inactivating enzyme, causes a marked loss in luminescence due to enzyme-mediated reduction in the intracellular tetracycline concentration
protocol for the nuclear transformation of Chlamydomonas reinhardtii using tetX as a selectable marker that confers stable resistance to tetracycline up to 100 microg/ml. TetX may be used to transform Chlamydomonas reinhardtii chloroplasts, related microalgae and other aerobic organisms sensitive to any tetracycline antibiotic
protocol for the nuclear transformation of Chlamydomonas reinhardtii using tetX as a selectable marker that confers stable resistance to tetracycline up to 100 microg/ml. TetX may be used to transform Chlamydomonas reinhardtii chloroplasts, related microalgae and other aerobic organisms sensitive to any tetracycline antibiotic
addition of Escherichia coli overexpressing TetX to soil bacterial enrichment cultures along with varying levels of tetracycline affects community-wide tetracycline resistance levels. Soil microbial communities develop lower levels of tetracycline resistance upon exposure to 25 microg/ml of tetracycline when an Escherichia coli expressing TetX is present (6% of cultivable bacteria are resistant to 40 microg/ml tetracycline). In the absence of TetX activity, a similar tetracycline exposure selects for greater levels of resistant bacteria in the soil microbial community (90% of cultivable bacteria are resistant to 40 microg/ml tetracycline)
addition of Escherichia coli overexpressing TetX to soil bacterial enrichment cultures along with varying levels of tetracycline affects community-wide tetracycline resistance levels. Soil microbial communities develop lower levels of tetracycline resistance upon exposure to 25 microg/ml of tetracycline when an Escherichia coli expressing TetX is present (6% of cultivable bacteria are resistant to 40 microg/ml tetracycline). In the absence of TetX activity, a similar tetracycline exposure selects for greater levels of resistant bacteria in the soil microbial community (90% of cultivable bacteria are resistant to 40 microg/ml tetracycline)
HOME
login
history
all enzymes
BRENDA home
History
1.14.13.231 tetracycline 11a-monooxygenase
more
top
Information
