Laboratory of Bacteriology and Mycology, National Institute of Agrarian and Veterinary Research (INIAV, IP), Oeiras, Portugal.
University of Évora, MED-Mediterranean Institute for Agriculture, Environment and Development, Évora, Portugal.
Microb Drug Resist. 2023 Mar;29(3):78-84. doi: 10.1089/mdr.2022.0228.
Antimicrobial resistance encoded by mobile colistin resistance () genes is a global and emergent threat. In this study, we report the occurrence of two different populations of colistin-resistant harboring and variants in the intestinal microbiome of a healthy pig. Following antimicrobial susceptibility determination, the presence of genes in two strains, isolated according to different selective microbiological procedures, was screened by PCR. Whole-genome sequencing confirmed that both strains were multidrug-resistant; INIAV_002EC was an AmpC producer carrying , , , genes, and INIAV_001EC carrying , , and genes, along with mutations in quinolone resistance-determining regions. In addition, both strains harbored , , and determinants. Further genome analysis revealed different plasmid replicons associated with the genes, IncX4 associated with , and ColE10 with . In addition, other replicons, including IncFIA, IncI1-Iγ, IncX1, IncY, in INIAV_002EC, and IncX1, IncI1, and p0111, in INIAV_001EC, were identified. Furthermore, both strains belonged to ST215 serotype O68:H12 and ST156 serotype O25:H28, respectively. This finding highlights the pig gut flora as a potential reservoir of mobile colistin resistance genes and reports the presence of the gene found for the first time in Portugal.
携带移动多粘菌素耐药基因 () 的抗菌药物耐药性是一个全球性的紧急威胁。在本研究中，我们报告了在健康猪的肠道微生物组中发现了两种不同的多粘菌素耐药 ，它们携带 和 变体。在进行抗菌药物敏感性测定后，根据不同的选择性微生物学程序分离出的两株 菌株中 基因的存在情况通过 PCR 进行了筛选。全基因组测序证实，这两株菌均为多药耐药菌；INIAV_002EC 是一种 AmpC 产生菌，携带 、 、 、 基因，而 INIAV_001EC 携带 、 和 基因，以及喹诺酮耐药决定区的突变。此外，两株菌均携带 、 和 决定子。进一步的基因组分析显示，与 基因相关的不同质粒复制子，IncX4 与 相关，ColE10 与 相关。此外，还鉴定了其他复制子，包括 IncFIA、IncI1-Iγ、IncX1、IncY，在 INIAV_002EC 中，以及 IncX1、IncI1 和 p0111，在 INIAV_001EC 中。此外，这两株菌分别属于 ST215 血清型 O68:H12 和 ST156 血清型 O25:H28。这一发现强调了猪肠道菌群可能是移动多粘菌素耐药基因的潜在储存库，并报告了葡萄牙首次发现的 基因的存在。
