Naemi Ali-Oddin, Dey Hymonti, Kiran Nosheen, Sandvik Sarah Torbergsen, Slettemeås Jannice Schau, Nesse Live L, Simm Roger
Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
Norwegian Veterinary Institute, Oslo, Norway.
Front Microbiol. 2020 Feb 4;11:104. doi: 10.3389/fmicb.2020.00104. eCollection 2020.
Polyether ionophores are antimicrobial compounds used as feed additives in poultry feed to control diseases caused by coccidia. In addition to the anticoccidial activity of these compounds, polyether ionophores also contain antibacterial properties. Resistance to the polyether ionophore narasin was recently shown to exist on mobile plasmids in and the resistance mechanism was suggested to be associated with a two-gene operon encoding an ABC-type transporter. In this study we demonstrate that the genes encoding the putative narasin resistance mechanism confers reduced susceptibility to the polyether ionophores narasin, salinomycin and maduramicin, but not to monensin and suggest that this resistance mechanism should be referred to as NarAB. Importantly, NarAB does not affect the susceptibility of to any of the tested antimicrobial compounds that are used in clinical medicine. However, we show that conjugation in the presence of certain polyether ionophores increases the number of vancomycin resistant suggesting that narasin and certain other polyether ionophores can contribute to the persistence of VRE in poultry populations.
聚醚离子载体是用作家禽饲料添加剂以控制由球虫引起的疾病的抗菌化合物。除了这些化合物的抗球虫活性外，聚醚离子载体还具有抗菌特性。最近发现对聚醚离子载体那拉菌素的耐药性存在于移动质粒上，并且耐药机制被认为与编码ABC型转运蛋白的双基因操纵子有关。在本研究中，我们证明编码假定的那拉菌素耐药机制的基因使对聚醚离子载体那拉菌素、盐霉素和马杜霉素的敏感性降低，但对莫能菌素不敏感，并表明这种耐药机制应称为NarAB。重要的是，NarAB不影响对临床医学中使用的任何测试抗菌化合物的敏感性。然而，我们表明在某些聚醚离子载体存在下的接合增加了耐万古霉素的数量，这表明那拉菌素和某些其他聚醚离子载体可导致家禽群体中耐万古霉素肠球菌的持续存在。
