Genetic evolution and clinical impact in extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae

Yong Chong, Yoshikiyo Ito, Tomohiko Kamimura

Research output: Contribution to journalReview articlepeer-review

98 Citations (Scopus)


The emergence of extended-spectrum β-lactamase (ESBL)-producing bacteria, particularly Escherichia coli and Klebsiella pneumoniae, is now a critical concern for the development of therapies against bacterial infection. ESBLs consist of three major genetic groups: TEM, SHV, and CTX-M types. Nosocomial infections due to TEM and SHV-producing K. pneumoniae strains were frequently documented until the late 1990s. The number of reports on community-acquired infections caused by CTX-M-producing E. coli strains have dramatically increased over the last decade; however, K. pneumoniae strains, of either the TEM or SHV types, are persistent and important ESBL producers. The spread of ESBL genes is associated with various mobile genetic elements, such as transposons, insertion sequences, and integrons. The rapid dissemination of ESBL genes of the CTX-M type may be related to highly complicated genetic structures. These structures harboring ESBL genes and mobile elements are found in a variety of plasmids, which often carry many other antibiotic resistance genes. Multidrug-resistant CTX-M-15-producing E. coli strains disseminate worldwide. Efficient mobile elements and plasmids may have accelerated the genetic diversity and the rapid spread of ESBL genes, and their genetic evolution has caused an emerging threat to the bacteria for which few effective drugs have been identified.

Original languageEnglish
Pages (from-to)1499-1504
Number of pages6
JournalInfection, Genetics and Evolution
Issue number7
Publication statusPublished - Oct 2011
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Ecology, Evolution, Behavior and Systematics
  • Molecular Biology
  • Genetics
  • Microbiology (medical)
  • Infectious Diseases


Dive into the research topics of 'Genetic evolution and clinical impact in extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae'. Together they form a unique fingerprint.

Cite this