發(fā)布時間：2017-12-31 06:05

  本文關(guān)鍵詞：3種喹諾酮類藥物對金黃色葡萄球菌及其耐藥突變體的體外抗菌活性研究　出處：《中國藥學雜志》2017年14期 　論文類型：期刊論文

  更多相關(guān)文章： 左氧氟沙星 莫西沙星 奈諾沙星 最低抑菌濃度 細菌恢復生長曲線

【摘要】：目的比較左氧氟沙星、莫西沙星和奈諾沙星對金黃色葡萄球菌的體外抗菌活性,初步探索金黃色葡萄球菌gyrA和parC基因突變對3種抗菌藥物耐藥性的影響及3種藥物對金黃色葡萄球菌gyrA和parC基因的優(yōu)先作用順序。方法利用瓊脂平板稀釋法測定左氧氟沙星、莫西沙星和奈諾沙星分別對50株金黃色葡萄球菌的最低抑菌濃度(minimal inhibitory concentration,MIC);測定4株已知特定基因位點細菌(其中RN450為實驗室菌株,已知基因序列,無任何位點突變)的MIC和防耐藥突變濃度(mutant prevention concentration,MPC),在已知MIC和MPC基礎(chǔ)上考察4株細菌的恢復生長細菌情況,對恢復生長細菌進行菌落計數(shù)并描記細菌恢復生長曲線。結(jié)果左氧氟沙星對50株金黃色葡萄球菌的MIC90(可抑制90%細菌生長的藥物濃度)(16μg·m L~(-1))分別是莫西沙星(2μg·m L~(-1))和奈諾沙星(0.5μg·m L~(-1))的8倍和32倍。從細菌恢復曲線上來看,在相同藥物濃度時,對于不同藥物來說,奈諾沙星的恢復生長細菌比例最小,而左氧氟沙星的恢復生長細菌比例最大;對于不同位點突變的細菌來說,RN450的恢復生長比例最小,而RN450A3的恢復生長比例最大。結(jié)論 3種藥物對金黃色葡萄球菌的體外抗菌活性強弱順序為:奈諾沙星莫西沙星左氧氟沙星;相較于左氧氟沙星和莫西沙星,奈諾沙星可在較低濃度時抑制細菌生長,且對不同基因位點突變細菌均有強大抑制作用。左氧氟沙星可能優(yōu)先作用于金黃色葡萄球菌的拓撲異構(gòu)酶Ⅳ的parC基因,而莫西沙星和奈諾沙星則可能幾乎同時作用于金黃色葡萄球菌DNA旋轉(zhuǎn)酶的gyrA基因和拓撲異構(gòu)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，

本文編號：1358464