Yu Yongfeng, Shao Changchun, Gong Xiaowei, Quan Heng, Liu Donghui, Chen Qiwei, Chu Yuefeng
State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China.
Lanzhou Institute for Food and Drug Control, Lanzhou 730050, China.
Microorganisms. 2022 Dec 8;10(12):2432. doi: 10.3390/microorganisms10122432.
There is no doubt that antimicrobial resistance (AMR) is a global threat to public health and safety, regardless of whether it’s caused by people or natural transmission. This study aimed to investigate the genetic characteristics and variations of tigecycline-resistant Gram-negative isolates from herbivores in northwest China. In this study, a total of 300 samples were collected from various provinces in northwest China, and 11 strains (3.67%) of tigecycline-resistant bacteria were obtained. In addition, bacterial identification and antibiotic susceptibility testing against 14 antibiotics were performed. All isolates were multiple drug-resistant (MDR) and resistant to more than three kinds of antibiotics. Using an Illumina MiSeq platform, 11 tigecycline-resistant isolates were sequenced using whole genome sequencing (WGS). The assembled draft genomes were annotated, and then sequences were blasted against the AMR gene database and virulence factor database. Several resistance genes mediating drug resistance were detected by WGS, including fluoroquinolone resistance genes (gyrA_S83L, gyrA_D87N, S83L, parC_S80I, and gyrB_S463A), fosfomycin resistance genes (GlpT_E448K and UhpT_E350Q), beta-lactam resistance genes (FtsI_D350N and S357N), and the tigecycline resistance gene (tetR N/A). Furthermore, there were five kinds of chromosomally encoded genetic systems that confer MDR (MarR_Y137H, G103S, MarR_N/A, SoxR_N/A, SoxS_N/A, AcrR N/A, and MexZ_K127E). A comprehensive analysis of MDR strains derived from WGS was used to detect variable antimicrobial resistance genes and their precise mechanisms of resistance. In addition, we found a novel ST type of Escherichia coli (ST13667) and a newly discovered point mutation (K127E) in the MexZ gene of Pseudomonas aeruginosa. WGS plays a crucial role in AMR control, prevention strategies, as well as multifaceted intervention strategies.
毫无疑问，无论抗微生物药物耐药性（AMR）是由人为因素还是自然传播引起的，它都是对公众健康和安全的全球威胁。本研究旨在调查中国西北地区食草动物中耐替加环素革兰氏阴性菌分离株的遗传特征和变异情况。在本研究中，从中国西北地区各省共采集了300份样本，获得了11株（3.67%）耐替加环素细菌。此外，进行了细菌鉴定和针对14种抗生素的药敏试验。所有分离株均为多重耐药（MDR），对三种以上抗生素耐药。使用Illumina MiSeq平台，对11株耐替加环素分离株进行了全基因组测序（WGS）。对组装后的基因组草图进行注释，然后将序列与AMR基因数据库和毒力因子数据库进行比对。通过WGS检测到了几种介导耐药性的耐药基因，包括氟喹诺酮耐药基因（gyrA_S83L、gyrA_D87N、S83L、parC_S80I和gyrB_S463A）、磷霉素耐药基因（GlpT_E448K和UhpT_E350Q）、β-内酰胺耐药基因（FtsI_D350N和S357N）以及替加环素耐药基因（tetR N/A）。此外，有五种染色体编码的遗传系统赋予MDR（MarR_Y137H、G103S、MarR_N/A、SoxR_N/A、SoxS_N/A、AcrR N/A和MexZ_K127E）。利用WGS对MDR菌株进行综合分析，以检测可变的抗微生物耐药基因及其精确的耐药机制。此外，我们发现了一种新型的大肠杆菌ST型（ST13667）和铜绿假单胞菌MexZ基因中新发现的点突变（K127E）。WGS在AMR控制、预防策略以及多方面干预策略中起着至关重要的作用。
