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Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
4-Quinolone interactions with gyrase subunit B inhibitors
C S Lewin1, B M Howard, J T Smith
1Department of Medical Microbiology, University of Edinburgh Medical School.
Journal of Medical Microbiology
|December 1, 1991
Summary
Combining DNA gyrase B subunit inhibitors like coumermycin with 4-quinolones (e.g., ciprofloxacin) antagonized their bactericidal activity against Staphylococcus. This suggests caution when assessing in vivo antimicrobial interactions.
Area of Science:
- Microbiology
- Pharmacology
- Biochemistry
Background:
- 4-quinolones inhibit DNA gyrase A subunit.
- Coumermycin and novobiocin inhibit DNA gyrase B subunit.
- Previous studies suggested synergy between these agents.
Purpose of the Study:
- To investigate the interaction between 4-quinolones and DNA gyrase B subunit inhibitors.
- To determine the bactericidal activity of combined antimicrobial agents.
Main Methods:
- Fixed and varying concentrations of ciprofloxacin/ofloxacin and coumermycin/novobiocin were used.
- Bactericidal activities were assessed in nutrient broth against Staphylococcus aureus E3T and S. warneri.
Main Results:
- Combined agents showed reduced bactericidal activity compared to 4-quinolones alone.
- Gyrase B subunit inhibitors antagonized the bactericidal effect of 4-quinolones.
- Findings align with previous in vivo studies showing reduced efficacy.
Conclusions:
- Antimicrobial interactions require assessment of both inhibitory and bactericidal activities.
- Potential antagonism between 4-quinolones and gyrase B subunit inhibitors in vivo.
- Results highlight the complexity of predicting antimicrobial synergy.
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