Key Laboratory of Medical Genetics of Zhejiang Province, Key Laboratory of Laboratory Medicine, Ministry of Education, Wenzhou Medical University, Wenzhou, China.
School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, China.
Front Cell Infect Microbiol. 2020 Jul 31;10:369. doi: 10.3389/fcimb.2020.00369. eCollection 2020.
Bacterial resistance to antibiotics has become an important concern for public health. This study was aimed to investigate the characteristics and the distribution of the florfenicol-related resistance genes in bacteria isolated from four farms. A total of 106 florfenicol-resistant Gram-negative bacilli were examined for florfenicol-related resistance genes, and the positive isolates were further characterized. The antimicrobial sensitivity results showed that most of them (100, 94.33%) belonged to multidrug resistance . About 91.51% of the strains carried gene, while 4.72% carried gene. According to the pulsed-field gel electrophoresis results, 34 were subdivided into 22 profiles, the genetic similarity coefficient of which ranged from 80.3 to 98.0%. The multilocus sequence typing (MLST) results revealed 17 sequence types (STs), with ST10 being the most prevalent. The genome sequencing result showed that the G32 genome consists of a 4.06-Mb chromosome, a 177,911-bp plasmid (pG32-177), and a 51,686-bp plasmid (pG32-51). A located in a drug-resistant region on the chromosome of G32 was with IS family transposase, and the other gene on the plasmid pG32-177 was with an IS insertion sequence. The gene was located on the pG32-51 flanked by IS element and TnpA26. This study suggested that the mobile genetic elements played an important role in the replication of resistance genes and the horizontal resistance gene transfer.
细菌对抗生素的耐药性已成为公共卫生的重要关注点。本研究旨在调查从四个农场分离的细菌中氟苯尼考相关耐药基因的特征和分布。共检测了 106 株氟苯尼考耐药革兰氏阴性杆菌的氟苯尼考相关耐药基因，对阳性分离株进行了进一步鉴定。药敏试验结果表明，它们大多（100 株，94.33%）属于多重耐药菌。约 91.51%的菌株携带 基因，而 4.72%的菌株携带 基因。根据脉冲场凝胶电泳结果，34 株菌可分为 22 种谱型，遗传相似系数为 80.3%～98.0%。多位点序列分型（MLST）结果显示有 17 种序列型（ST），其中 ST10 最为流行。基因组测序结果显示， G32 基因组由一个 4.06-Mb 染色体、一个 177911-bp 质粒（pG32-177）和一个 51686-bp 质粒（pG32-51）组成。一个 位于 G32 染色体耐药区的基因带有 IS 家族转座酶，另一个质粒 pG32-177 上的 基因带有 IS 插入序列。 基因位于 pG32-51 质粒上，由 IS 元件和 TnpA26 侧翼。本研究表明，移动遗传元件在耐药基因的复制和水平基因转移中发挥了重要作用。
