Related Experiment Video

Updated: Aug 15, 2026

Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)
08:21

Site-specific Bacterial Chromosome Engineering: ΦC31 Integrase Mediated Cassette Exchange (IMCE)

Published on: March 16, 2012

Imipenem-resistant Achromobacter xylosoxidans carrying blaVIM-2-containing class 1 integron

Kyeong Seob Shin1, Kyudong Han, Jungnam Lee

  • 1Department of Laboratory Medicine, College of Medicine, Chungbuk National University, Cheongju, 361-711 Republic of Korea. ksshin@chungbuk.ac.kr

Diagnostic Microbiology and Infectious Disease
|November 2, 2005
PubMed

Insights

This study identified imipenem-resistant Achromobacter xylosoxidans in Korean ICUs, producing VIM-2 and OXA-30 beta-lactamases. These findings suggest a single clone responsible for multidrug resistance, highlighting a significant clinical challenge.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Achromobacter xylosoxidans is an opportunistic pathogen often found in healthcare settings.
  • Imipenem resistance in A. xylosoxidans is a growing concern, particularly in intensive care units (ICUs).
  • Understanding the genetic mechanisms of resistance is crucial for effective treatment strategies.

Purpose of the Study:

  • To characterize imipenem-resistant Achromobacter xylosoxidans isolates from a Korean tertiary hospital ICU.
  • To identify the specific beta-lactamases responsible for imipenem resistance.
  • To investigate the clonal origin and genetic relatedness of these resistant isolates.

Main Methods:

  • Isoelectric focusing, polymerase chain reaction (PCR), and DNA sequencing were used to identify beta-lactamases.
  • Antimicrobial susceptibility testing (antibiogram) was performed for various antibiotic classes.
  • Random amplified polymorphic DNA (RAPD) analysis was employed for DNA fingerprinting.
  • Integron structure analysis was conducted on a representative isolate.

Main Results:

  • All seven isolates produced VIM-2, OXA-30, and chromosomal AmpC beta-lactamases.
  • Isolates exhibited resistance to beta-lactams (including imipenem) and all tested aminoglycosides.
  • RAPD analysis indicated that all isolates originated from a single clone.
  • The bla(VIM-2) gene was located within a class 1 integron containing aacA4 gene cassettes.

Conclusions:

  • This is the first report of bla(VIM-2) in Achromobacter xylosoxidans.
  • The presence of VIM-2, OXA-30, and AmpC beta-lactamases contributes to the multidrug resistance phenotype.
  • The clonal nature of the isolates suggests successful transmission within the ICU setting.
  • These findings underscore the need for vigilant surveillance and infection control measures against resistant A. xylosoxidans.

More Related Videos

Screening Foodstuffs for Class 1 Integrons and Gene Cassettes09:37

Screening Foodstuffs for Class 1 Integrons and Gene Cassettes

Published on: June 19, 2015

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance09:00

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance

Published on: May 2, 2018

Related Concept Videos

Antibiotic Selection00:57

Antibiotic Selection

Overview
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Production of Antibiotics01:27

Production of Antibiotics

Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...