Zhang Xiaoyan, Zhou Qian, Tang Mengjun, Pu Junhua, Zhang Jing, Lu Junxian, Zhang Yunzeng, Gao Yushi
Supervision, Inspection & Testing Centre for Poultry Quality (Yangzhou), Ministry of Agriculture, Jiangsu Institute of Poultry Science, Yangzhou, China.
Jiangsu Key Lab of Zoonosis, Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China.
Front Microbiol. 2021 Oct 8;12:716185. doi: 10.3389/fmicb.2021.716185. eCollection 2021.
is a major food-borne pathogen in humans, and previous studies reported a high prevalence of gentamicin-resistant isolates from food-producing animals in China. This study aimed to investigate the aminoglycoside resistance of isolated from chicken and swine in Jiangsu province, China and understand the possible mechanisms responsible for aminoglycoside resistance. One hundred and eighty-five isolates of chicken and swine origins in 2017 and 2018 were analyzed for gentamicin and kanamycin resistance. Some aminoglycoside resistance genes were selected for PCR detection in all strains. The genomic DNAs of two strains with high resistance to gentamicin were used as donors to subject NCTC11168 to natural transformation. The transformants were investigated by whole-genome sequencing and analyzed comparatively with NCTC11168. In total, 30.5% (29/95) of isolates and 42.2% (38/90) of isolates were resistant to gentamicin and kanamycin. The prevalence of the gene and gene was 65.4% (121/185) and 36.2% (67/185) in isolates, respectively. The cluster was identified in 8.7% (8/92) and 20.4% (19/93) of all isolates in each year. With each donor DNA, aminoglycoside-resistant transformants were obtained. The transformants showed ≥128-fold increases in the MICs of gentamicin, kanamycin, and tobramycin. A 5200-bp segment was found to be inserted between the highly conserved genes and of . A total of 9.7% (18/185) strains showing high resistance to aminoglycosides had this segment by PCR detection. The genetic diversity of the insertion-fragment positive strains was determined by MLST, and seven sequence types were identified for these strains.
是人类主要的食源性病原体，先前的研究报道中国食品生产动物中庆大霉素耐药分离株的流行率很高。本研究旨在调查从中国江苏省鸡和猪中分离的菌株对氨基糖苷类抗生素的耐药性，并了解导致氨基糖苷类耐药的可能机制。对2017年和2018年分离的185株鸡源和猪源菌株进行了庆大霉素和卡那霉素耐药性分析。在所有菌株中选择一些氨基糖苷类耐药基因进行PCR检测。以两株对庆大霉素高度耐药的菌株的基因组DNA作为供体，对NCTC11168进行自然转化。通过全基因组测序对转化子进行研究，并与NCTC11168进行比较分析。总共，29/95（30.5%）的鸡源菌株和38/90（42.2%）的猪源菌株对庆大霉素和卡那霉素耐药。鸡源菌株中aac(6’)-Ib基因和aph(3’)-IIa基因的流行率分别为65.4%（121/185）和36.2%（67/185）。每年所有鸡源菌株中分别有8.7%（8/92）和20.4%（19/93）鉴定出aac(6’)-Ib-cr簇。用每个供体DNA都获得了氨基糖苷类耐药转化子。这些转化子对庆大霉素、卡那霉素和妥布霉素的最低抑菌浓度（MIC）增加了≥128倍。发现一个5200bp的片段插入到NCTC11168的高度保守基因rpsL和rrs之间。通过PCR检测，总共9.7%（18/185）对氨基糖苷类抗生素高度耐药的菌株有该片段。通过多位点序列分型（MLST）确定了插入片段阳性菌株的遗传多样性，这些菌株鉴定出了7种序列类型。
