3种喹诺酮类药物对金黄色葡萄球菌及其耐药突变体的体外抗菌活性研究

发布时间：2017-12-31 06:05

  本文关键词：3种喹诺酮类药物对金黄色葡萄球菌及其耐药突变体的体外抗菌活性研究　出处：《中国药学杂志》2017年14期 　论文类型：期刊论文

  更多相关文章： 左氧氟沙星 莫西沙星 奈诺沙星 最低抑菌浓度 细菌恢复生长曲线

【摘要】：目的比较左氧氟沙星、莫西沙星和奈诺沙星对金黄色葡萄球菌的体外抗菌活性,初步探索金黄色葡萄球菌gyrA和parC基因突变对3种抗菌药物耐药性的影响及3种药物对金黄色葡萄球菌gyrA和parC基因的优先作用顺序。方法利用琼脂平板稀释法测定左氧氟沙星、莫西沙星和奈诺沙星分别对50株金黄色葡萄球菌的最低抑菌浓度(minimal inhibitory concentration,MIC);测定4株已知特定基因位点细菌(其中RN450为实验室菌株,已知基因序列,无任何位点突变)的MIC和防耐药突变浓度(mutant prevention concentration,MPC),在已知MIC和MPC基础上考察4株细菌的恢复生长细菌情况,对恢复生长细菌进行菌落计数并描记细菌恢复生长曲线。结果左氧氟沙星对50株金黄色葡萄球菌的MIC90(可抑制90%细菌生长的药物浓度)(16μg·m L~(-1))分别是莫西沙星(2μg·m L~(-1))和奈诺沙星(0.5μg·m L~(-1))的8倍和32倍。从细菌恢复曲线上来看,在相同药物浓度时,对于不同药物来说,奈诺沙星的恢复生长细菌比例最小,而左氧氟沙星的恢复生长细菌比例最大;对于不同位点突变的细菌来说,RN450的恢复生长比例最小,而RN450A3的恢复生长比例最大。结论 3种药物对金黄色葡萄球菌的体外抗菌活性强弱顺序为:奈诺沙星莫西沙星左氧氟沙星;相较于左氧氟沙星和莫西沙星,奈诺沙星可在较低浓度时抑制细菌生长,且对不同基因位点突变细菌均有强大抑制作用。左氧氟沙星可能优先作用于金黄色葡萄球菌的拓扑异构酶Ⅳ的parC基因,而莫西沙星和奈诺沙星则可能几乎同时作用于金黄色葡萄球菌DNA旋转酶的gyrA基因和拓扑异构酶Ⅳ的parC基因。
[Abstract]:Objective to compare the in vitro antibacterial activities of levofloxacin, moxifloxacin and nenofloxacin against Staphylococcus aureus. To explore the effect of gyrA and parC gene mutation of Staphylococcus aureus on the drug resistance of three antimicrobial agents and the priority of the three drugs to the gyrA and parC genes of Staphylococcus aureus. Methods Levofloxacin was determined by Agar plate dilution method. The minimum inhibitory concentration of moxifloxacin and nenofloxacin against 50 strains of Staphylococcus aureus were determined. Four strains of bacteria with known specific gene loci (RN450 were laboratory strains and known gene sequences) were determined. There was no mutation at any locus) of MIC and the concentration of anti-drug resistance prevention concentration (MPCs). On the basis of known MIC and MPC, we investigated the growth recovery bacteria of four strains of bacteria. The bacteria were counted and the growth curve was recorded. Results levofloxacin could inhibit the growth of 90% strains of Staphylococcus aureus by MIC90 (the drug concentration of levofloxacin inhibited the growth of 90% strains of Staphylococcus aureus). (16 渭 g 路mL ~ (-1)) moxifloxacin (2 渭 g 路m ~ (-1)) and nenofloxacin (0.5 渭 g 路m ~ (-1)). From the bacterial recovery curve. At the same concentration, for different drugs, nenofloxacin had the lowest proportion of growth regurgitation bacteria, while levofloxacin had the largest proportion of regurgitating bacteria. For the bacteria with different locus mutation, the proportion of RN450 regrowth was the lowest. Conclusion the antimicrobial activity of three drugs against Staphylococcus aureus in vitro is in the order of nenofloxacin moxifloxacin levofloxacin; Compared with levofloxacin and moxifloxacin, nenofloxacin inhibited bacterial growth at lower concentrations. Levofloxacin may preferentially affect the parC gene of topoisomerase 鈪，

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