Evolution and Comparative Genomics of F33:A−:B− Plasmids Carrying bla CTX-M-55 or bla CTX-M-65 in Escherichia coli and Klebsiella pneumoniae Isolated from Animals, Food Products, and Humans in China
Published: 2018
Abstract:
Worldwide spread of antibiotic resistance genes among
Enterobacteriaceae
isolates is of great concern. F33:A−:B− plasmids are important vectors of resistance genes, such as
bla
CTX-M-55/-65
,
bla
NDM-1
,
fosA3
, and
rmtB
, among
E. coli
isolates from various sources in China. We determined and compared the complete sequences of 17 F33:A−:B− plasmids from various sources. These plasmids appear to have evolved from the same ancestor by mobile element-mediated rearrangement, acquisition, and/or loss of resistance modules and similar IncN1, IncI1, and/or IncX1 plasmid backbone segments. Our findings highlight the evolutionary potential of F33:A−:B− plasmids as efficient vectors to capture and diffuse clinically relevant resistance genes.
