喹诺酮类与磺胺类药物对枯草芽孢杆菌与大肠杆菌的联合毒性及其机制初探  

The combined toxicity of quinolones and sulfonamides on Bacillus subtilis and Escherichia coli

作　　者：苏冰梅[1] 王婷[2] 方淑霞[2] 龙茜[2] 林志芬[2] 林娟[1] 

机构地区：[1]福州大学福建省海洋酶工程重点实验室,福州350116 [2]污染控制与资源化研究国家重点实验室,同济大学环境科学与工程学院,上海200092

出　　处：《环境化学》2015年第11期1975-1980,共6页Environmental Chemistry

基　　金：同济大学污染控制与资源化研究国家重点实验室自主研究项目(PCRRY11003);国家自然科学基金(201177092,21377096);中央高校基本科研业务费专项资金(0400219181)资助

摘　　要：以枯草芽孢杆菌(Bacillus subtilis 168)与大肠杆菌(Escherichia coli K12 MG-1655)为实验材料,以3种喹诺酮类药物及典型磺胺类药物为研究对象,分别测定了喹诺酮类药物与磺胺类药物对枯草芽孢杆菌与大肠杆菌的单一毒性及两类药物的联合效应,并对其毒性机制进行初步探讨.研究结果表示,磺胺类药物与喹诺酮类药物对枯草芽孢杆菌的毒性比对大肠杆菌的毒性小,可能是因为枯草芽孢杆菌的细胞壁较厚且富含肽聚糖,导致磺胺类药物与喹诺酮类药物较难进入枯草芽孢杆菌,毒性较低;同时大部分磺胺类药物与枯草芽孢杆菌的靶蛋白的结合能力低于其与大肠杆菌的靶蛋白的结合能力也是磺胺类药物对枯草芽孢杆菌的毒性比对大肠杆菌的毒性小的另一原因.喹诺酮类药物与磺胺类药物对枯草芽孢杆菌的联合效应表现为拮抗,而对大肠杆菌的联合效应则表现为相加.这两类药物有不同的联合效应,可能是由于枯草芽孢杆菌能够在磺胺类药物的作用下产生芽孢这一抗逆性构造,减弱喹诺酮类药物的杀菌作用.The present paper investigated the individual and combined toxicity of quinolones and sulfonamides on Bacillus subtilis168（ B. subtilis） and Escherichia coli K12 MG1655（ E. coli）. Our results revealed that both the quinolones and sulfonamides were less toxic to B. subtilis than E. coli.It was likely because that the cell wall of B. subtilis is much thicker than that of E. coli and the tightly crosslinked peptidoglycan layer is abundant in B. subtilis,which may act as a barrier to the quinolones and sulfonamides,thereby leading to greater resistance of B. subtilis to the drugs.Molecular docking results showed the most sulfonamides has a stronger binding affinity with the target protein from E. coli than that from B. subtilis,which also explained the higher toxicity of the sulfonamides on E. coli than on B. subtilis. It was also found that the quinolones and sulfonamidespresented antagonistic effects on B. subtilis but additive effects on the E.coli. The antagonistic effects of the quinolones and sulfonamides on the B. subtilis were probably due to the inclination of the B.subtilis to form spores under the stress of the sulfonamides,which weakened the antibacterial effects of the quinolones.

关 键 词：喹诺酮类药物 磺胺类药物 枯草芽孢杆菌 大肠杆菌 联合毒性 

分 类 号：X171.5[环境科学与工程—环境科学]