DNA cleavage activities of Staphylococcus aureus gyrase and topoisomerase IV stimulated by quinolones and 2-pyridones.
We have cloned Staphylococcus aureus DNA gyrase and topoisomerase IV and expressed them in Escherichia coli as polyhistidine-tagged proteins to facilitate purification and eliminate contamination by host enzymes. The enzyme preparations had specific activities similar to previously reported values. Potassium glutamate (K-Glu) stimulated the drug-induced DNA cleavage activity and was optimal between 100 and 200 mM for gyrase and peaked at 100 mM for topoisomerase IV. Higher concentrations of K-Glu inhibited the cleavage activities of both enzymes. Using a common buffer system containing 100 mM K-Glu, we tested the enzyme-mediated DNA cleavage activities of both gyrase and topoisomerase IV with oxolinic acid, norfloxacin, ciprofloxacin, trovafloxacin, clinafloxacin, and the 2-pyridone ABT-719. As expected, all drugs tested demonstrated greater potency against topoisomerase IV than against gyrase. In addition, cleavage activity was found to correlate well with antibacterial activity.
Saiki
A Y
AY
Abbott Laboratories, Infectious Disease Research, Abbott Park, Illinois 60064-3537, USA.
Shen
L L
LL
Chen
C M
CM
Baranowski
J
J
Lerner
C G
CG
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D004247:DNA / Q000378:metabolism*; D027101:DNA Topoisomerase IV; D004250:DNA Topoisomerases, Type II / Q000302:isolation & purification / Q000378:metabolism*; D024841:Fluoroquinolones; D011728:Pyridones / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000201:enzymology*
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D011728:Pyridones; D004247:DNA; C093440:ABT 719; D027101:DNA Topoisomerase IV; D004250:DNA Topoisomerases, Type II