Dündar Tansu, Köksal Çakırlar Fatma
Istanbul University-Cerrahpaşa, Cerrahapaşa Medical Faculty, Department of Medical Microbiology, Istanbul, Turkey.
Res Microbiol. 2025 Jul-Aug;176(5-6):104298. doi: 10.1016/j.resmic.2025.104298. Epub 2025 Apr 8.
Coagulase-negative staphylococci (CNS) are emerging as significant contributors to antimicrobial resistance, yet their genomic characteristics remain incompletely understood. This study presents a whole-genome analysis of 12 multidrug-resistant CNS strains (Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus hominis) isolated from blood cultures, focusing on antimicrobial resistance genes, mobile genetic elements (MGEs), and horizontal gene transfer (HGT) mechanisms. We identified 22 resistance genes conferring resistance to 11 antimicrobial classes, many of which were plasmid-associated. Notably, we report the first detection of the ISSha1 insertion sequence in S. hominis, along with novel resistance plasmids, including pGO1 and VRSAp in S. haemolyticus and pAMα1 in S. hominis. The identification of bacteriophage-derived sequences in S. haemolyticus and S. hominis suggests a role for phages in genetic exchange. CRISPR sequences and a Cas gene were detected in S. hominis, suggesting a potential but unconfirmed role in restricting gene transfer. Additionally, pGO1 was identified as a conjugative plasmid, while pAMα1 and VRSAp were determined to be mobilizable, reinforcing the role of CNS in resistance dissemination. These results highlight CNS as reservoirs of antimicrobial resistance genes and emphasize the importance of species-specific genomic surveillance. Proactive monitoring of CNS is crucial for controlling antimicrobial resistance in clinical settings.
凝固酶阴性葡萄球菌（CNS）正逐渐成为抗菌药物耐药性的重要贡献者，但其基因组特征仍未完全了解。本研究对从血培养物中分离出的12株多重耐药CNS菌株（表皮葡萄球菌、溶血葡萄球菌、人葡萄球菌）进行了全基因组分析，重点关注抗菌药物耐药基因、移动遗传元件（MGEs）和水平基因转移（HGT）机制。我们鉴定出22个赋予对11类抗菌药物耐药性的耐药基因，其中许多与质粒相关。值得注意的是，我们首次在人葡萄球菌中检测到ISSha1插入序列，以及新型耐药质粒，包括溶血葡萄球菌中的pGO1和VRSAp以及人葡萄球菌中的pAMα1。在溶血葡萄球菌和人葡萄球菌中鉴定出噬菌体衍生序列，表明噬菌体在基因交换中发挥作用。在人葡萄球菌中检测到CRISPR序列和一个Cas基因，表明其在限制基因转移方面可能但未得到证实的作用。此外，pGO1被鉴定为接合质粒，而pAMα1和VRSAp被确定为可移动质粒，这强化了CNS在耐药性传播中的作用。这些结果突出了CNS作为抗菌药物耐药基因库的地位，并强调了物种特异性基因组监测的重要性。对CNS进行主动监测对于控制临床环境中的抗菌药物耐药性至关重要。
