Lewin C S, Howard B M, Smith J T
Department of Medical Microbiology, University of Edinburgh Medical School.
J Med Microbiol. 1991 Dec;35(6):358-62. doi: 10.1099/00222615-35-6-358.
In studies which have involved determination of fractional inhibitory concentrations, synergy has been described between the 4-quinolones, which inhibit the A subunit of DNA gyrase, and either coumermycin or novobiocin, which inhibit the B subunit of the same enzyme. In this study, fixed concentrations of ciprofloxacin or ofloxacin were combined with varying concentrations of coumermycin or novobiocin and vice versa in nutrient broth. The bactericidal activities of the different mixtures against either Staphylococcus aureus E3T or S. warneri were determined and found to be less than those of equivalent concentrations of either 4-quinolone alone. The observation that gyrase B subunit inhibitors antagonised the bactericidal activity of 4-quinolones is in accordance with the report previously made by others that ciprofloxacin combined with coumermycin was less effective than ciprofloxacin alone in treating staphylococcal endocarditis in rats. Our results indicate that both inhibitory and bactericidal activity should be taken into account when assessing possible interactions in vivo between 4-quinolones and other antimicrobial agents.
在涉及测定部分抑制浓度的研究中，已发现抑制DNA旋转酶A亚基的4-喹诺酮类药物与抑制同一种酶B亚基的香豆霉素或新生霉素之间存在协同作用。在本研究中，将固定浓度的环丙沙星或氧氟沙星与不同浓度的香豆霉素或新生霉素在营养肉汤中混合，反之亦然。测定了不同混合物对金黄色葡萄球菌E3T或华纳葡萄球菌的杀菌活性，发现其低于同等浓度的任何一种单独的4-喹诺酮类药物。旋转酶B亚基抑制剂拮抗4-喹诺酮类药物杀菌活性的观察结果与其他人先前的报告一致，即环丙沙星与香豆霉素联合使用在治疗大鼠葡萄球菌性心内膜炎方面比单独使用环丙沙星效果更差。我们的结果表明，在评估4-喹诺酮类药物与其他抗菌药物在体内可能的相互作用时，应同时考虑抑制活性和杀菌活性。
