Fecal Carriage of <i>Escherichia coli</i> Harboring the <i>tet</i>(X4)-IncX1 Plasmid from a Tertiary Class-A Hospital in Beijing, China
Weishuai Zhai,
Yingxin Tian,
Dongyan Shao,
Muchen Zhang,
Jiyun Li,
Huangwei Song,
Chengtao Sun,
Yang Wang,
Dejun Liu,
Ying Zhang
Affiliations
Weishuai Zhai
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Yingxin Tian
Department of Laboratory Medicine, the First Medical Centre, Chinese PLA General Hospital, Beijing 100853, China
Dongyan Shao
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Muchen Zhang
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Jiyun Li
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Huangwei Song
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Chengtao Sun
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Yang Wang
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Dejun Liu
Key Laboratory of Animal Antimicrobial Resistance Surveillance, Ministry of Agriculture and Rural Affairs, and Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Ying Zhang
Department of Laboratory Medicine, the First Medical Centre, Chinese PLA General Hospital, Beijing 100853, China
The emergence of the mobile tigecycline-resistance gene, tet(X4), poses a significant threat to public health. To investigate the prevalence and genetic characteristics of the tet(X4)-positive Escherichia coli in humans, 1101 human stool samples were collected from a tertiary class-A hospital in Beijing, China, in 2019. Eight E. coli isolates that were positive for tet(X4) were identified from clinical departments of oncology (n = 3), hepatology (n = 2), nephrology (n = 1), urology (n = 1), and general surgery (n = 1). They exhibited resistance to multiple antibiotics, including tigecycline, but remained susceptible to meropenem and polymyxin B. A phylogenetic analysis revealed that the clonal spread of four tet(X4)-positive E. coli from different periods of time or departments existed in this hospital, and three isolates were phylogenetically close to the tet(X4)-positive E. coli from animals and the environment. All tet(X4)-positive E. coli isolates contained the IncX1-plasmid replicon. Three isolates successfully transferred their tigecycline resistance to the recipient strain, C600, demonstrating that the plasmid-mediated horizontal gene transfer constitutes another critical mechanism for transmitting tet(X4). Notably, all tet(X4)-bearing plasmids identified in this study had a high similarity to several plasmids recovered from animal-derived strains. Our findings revealed the importance of both the clonal spread and horizontal gene transfer in the spread of tet(X4) within human clinics and between different sources.
