摘要

畜牧业相关的耐甲氧西林金黄色葡萄球菌（LA-MRSA）已在全球范围内出现。除了耐甲氧西林外，LA-MRSA还可能携带多种新型和不常见的抗微生物耐药基因。在凝固酶阴性葡萄球菌（CoNS）和金黄色葡萄球菌中发生相同的抗性基因表明，LA-MRSA和其他葡萄球菌之间正在进行遗传交换，但其农场环境生态位的驱动力仍然知之甚少。为了评估CoNS作为抗生素抗性基因假定储库的潜力，我们分析了德国41个养猪场获得的灰尘和粪便样品中CoNS的抗菌药物敏感性，其中大多数（41/41）中有LA-MRSA / MSSA历史。在所分析的344株分离株中，鉴定出18种不同的CoNS物种，而S. sciuri代表最普遍的物种（46％）。四环素（71％），青霉素（65％）和苯唑西林（64％）以及夫西地酸（50％）检测到高耐药率，这主要是由于S. sciuri菌株易感性降低。 S. sciuri表现出显着的多抗性，并且许多分离株的特征在于携带许多不常见的（多）抗性基因（例如cfr，apmA，fexA）以及降低对诸如利奈唑胺和达托霉素的最后手段抗生素的易感性。综合数据表明S. sciuri具有显着的抗性基因库，需要进一步关注。我们假设这个物种的成员由于其灵活的生活方式可能有助于这些基因在家畜环境中的传播。

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have globally emerged in animal husbandry. In addition to methicillin resistance, LA-MRSA may carry a variety of novel and uncommon antimicrobial resistance genes. Occurrence of the same resistance genes in coagulase-negative staphylococci (CoNS) and S. aureus suggests an ongoing genetic exchange between LA-MRSA and other staphylococci whose driving forces in the ecological niche of the farm environment are, however, still poorly understood. To assess the potential of CoNS as putative reservoirs for antibiotic resistance genes, we analysed the antimicrobial susceptibility of CoNS from dust and manure samples obtained in 41 pig farms in Germany, most of them (36 of 41) with a proven LA-MRSA/MSSA history. Among the 344 isolates analysed, 18 different CoNS species were identified and S. sciurirepresented the most prevalent species (46%). High resistance rates were detected for tetracycline (71%), penicillin (65%) and oxacillin (64%) as well as fusidic acid (50%), which was mainly due to reduced susceptibility among S. sciuri isolates. S. sciuri exhibited pronounced multiresistance, and many isolates were characterised by the carriage of a number of uncommon (multi)resistance genes (e.g. cfr, apmA, fexA) and decreased susceptibility towards last resort antibiotics such as linezolid and daptomycin. The combined data suggest that S. sciuri harbours a significant resistance gene pool that requires further attention. We hypothesise that members of this species, due to their flexible lifestyle, might contribute to the spread of such genes in livestock environments.

https://www.sciencedirect.com/science/article/pii/S037811351630102X