In:
Frontiers in Microbiology, Frontiers Media SA, Vol. 14 ( 2023-5-18)
Abstract:
Extended-spectrum beta-lactamase-producing Gram-negative bacteria are common in the community and hospitals. To monitor ESBLs mediated by the CTX-M genotype, we collected clinical ESBL pathogenic strains from a hospital in central China and observed a strain of Escherichia coli , namely Ec15103 carrying bla CTX–M–14 , bla CTX–M–64 and bla TEM–1 , isolated from the blood of a 7-day-old infant in 2015. Strain Ec15103 contains two drug resistance plasmids: pEc15103A, an IncFI-type plasmid that cannot be conjugatively transferred and carries the drug resistance genes bla TEM–1 , aacC2 , aadA5 , sul1 , mph (A), sul2 , strAB , and tetA (A); and pEc15103B, an IncK2/Z-type plasmid that carries the conjugation transfer gene and bla CTX–M–14 . In addition, bla CTX–M–64 is located on the chromosome of Ec15103, and it is the first report of pathogen with bla CTX–M–64 located on its chromosome (the search terms used “blaCTX-M-64” and “chromosome”). bla CTX–M–14 and bla CTX–M–64 are carried by IS Ecp1 -mediated transposon Tn 6503a and Tn 6502 , respectively. The conjugation transfer ability of pEc15103B was significantly inhibited by zidovudine (AZT) and linoleic acid (LA) and that expression of bla CTX–M–14 , bla CTX–M–64 and bla TEM–1 at the mRNA level did not change based on the concentration of cefotaxime or ampicillin. Co-occurrence of bla CTX–M–14 and bla CTX–M–64 in a single isolate will enhance the drug resistance of bacteria, and the presence of bla CTX–M–64 in the chromosome may make the resistance more maintain. This fact will facilitate its dissemination and persistence under different antimicrobial selection pressures. It is essential to prevent these strains from further spreading in a hospital environment.
Type of Medium:
Online Resource
ISSN:
1664-302X
DOI:
10.3389/fmicb.2023.1158659
DOI:
10.3389/fmicb.2023.1158659.s001
Language:
Unknown
Publisher:
Frontiers Media SA
Publication Date:
2023
detail.hit.zdb_id:
2587354-4
