Molecular mechanisms and genomic basis of tigecycline-resistant Enterobacterales from swine slaughterhouses
Yükleniyor...
Dosyalar
Tarih
2022
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Gmbh
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
The continuous emergence of tigecycline-resistant bacteria is undermining the effectiveness of clinical tigecy-cline. Environmental tigecycline-resistant bacteria have the potential to infect humans through human -environment interactions. Furthermore, the mechanisms of tigecycline resistance in Enterobacterales are complicated. In this study, we aimed to investigate the additional pathways of tigecycline resistance in envi-ronmental Enterobacterales besides tet(X) and tmexCD-toprJ. During the years 2019-2020, tigecycline-resistant Enterobacterales (n = 45) negative for tet(X) and tmexCD-toprJ were recovered from 328 different samples from two slaughterhouses. Five distinct bacteria species were identified, of which Klebsiella pneumoniae (n = 37) was the most common, with K. pneumoniae ST45 and ST35 being the predominant clones. Tigecycline resistance determinants analysis showed that tet(A) mutations and ramR inactivation were the most prevalent mechanisms for tigecycline resistance in the 45 strains. Two known tet(A) variants (type 1 and tet(A)-v) and one novel tet(A) variant (type 3) were identified. Cloning experiments confirmed that the novel type 3 tet(A) could enhance the 4 -fold MIC for tigecycline. Inactivation of ramR was induced by either point mutations or indels of sequences, which could result in the overexpression of AcrAB pump genes leading to tigecycline resistance. In addition, all isolates were resistant to a wide range of antimicrobials and carried various resistance genes. These findings enriched the epidemiological and genomic characterizations of tigecycline-resistant Enterobacterales from slaughterhouses and contributed to a better understanding of the complex mechanisms of tigecycline resistance in environmental bacteria.
Açıklama
Anahtar Kelimeler
Slaughterhouse environment, Tigecycline resistance, tet(A), Transmission, Mobile elements
Kaynak
Microbiological Research
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
264
