One strain of
Escherichia coli
that had high levels of resistance to
cefotaxime was isolated from a patient infected with
S. sonnei
. Isoelectric
focusing showed that the
E. coli
and
S. sonnei
strains produced a
b
-lactamase
with an isoelectric point of 8.1. Moreover, polymerase chain reaction analysis
indicated that both strains possessed the same DNA sequences for CTX-M-14. The
results of
in vitro
and
in vivo
conjugation showed that the efficiency of CTX-M-14
transfer from
S. sonnei
to
E. coli
was similar to CTX-M-14 transfer between
E. coli
strains.
Conclusion:
The data suggest that the acquisition of the extended-spectrum
b
-
lactamases gene by pathogenic bacteria in the human intestinal tract to
commensal microbiome bacteria can cause serious infectious diseases.