Diversity of carbapenem resistance mechanisms in Acinetobacter baumannii from a Taiwan hospital: spread of plasmid-borne OXA-72 carbapenemase

Lu, Po‐Liang; Doumith, Michel; Livermore, David M.; Chen, Tyen-Po; Woodford, Neil

doi:10.1093/jac/dkn553

Cited by 84 publications

(80 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, a PCR amplicon for the carO gene of approximately 1700 bp, which was larger than the expected size of 741 bp, was obtained from strain 2b, suggestive of a CarO OMP defect. Lee et al (2011) and Lu et al (2009) reported that the loss of the CarO OMP had only a minor effect on carbapenem resistance in A. baumannii. Bratu et al (2008) reported that the loss of the CarO OMP did not correlate with carbapenem resistance.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Diverse carbapenem-resistance mechanisms in 16S rRNA methylase-producing Acinetobacter baumannii

Yamada

Suwabe

2013

Journal of Medical Microbiology

View full text Add to dashboard Cite

Multidrug-resistant Acinetobacter baumannii has become a global problem. This study characterized amikacin-resistant A. baumannii isolated from eight patients during April 2010-March 2011 in our university hospital and examined the possible mechanisms in three cases in which carbapenem susceptibility changed to carbapenem resistance during treatment of the patients. The armA gene, which is one of the 16S rRNA methylase genes and is associated with high MICs of aminoglycosides, was positive in all isolates. The bla OXA-51 gene and ISAba1 and ISAba1-bla ADC were positive in all isolates, but ISAba1-bla OXA-51 was positive in only three isolates. The CarO outer-membrane protein was lost in one isolate. In the first case, both the susceptible and the resistant isolates were positive for ISAba1-bla OXA-51 , but the expression of the bla ADC gene was increased 3.1-fold in the carbapenem-resistant isolate of the pair. In the second case, the carbapenem-resistant strain became positive for ISAba1-bla OXA-51 , resulting in 21.5-fold increased expression of bla OXA-51 , compared to the carbapenem-susceptible strain of the pair. In the third case, the carbapenemase genes remained negative despite the carbapenem resistance, but the expression of the adeB gene was increased 4.6-fold after acquisition of carbapenem resistance. Multilocus sequence typing analysis of two isolates showing representative pulsed-field gel electrophoresis patterns demonstrated that both isolates were classified to sequence type 2 (ST2). These results showed that the 16S rRNA methylaseproducing A. baumannii, initially susceptible to carbapenem, acquired carbapenem resistance via diverse mechanisms.

show abstract

Section: Discussionmentioning

confidence: 99%

“…ISAba1, ISAba1-bla OXA-51-like and ISAba1-bla ADC were detected by PCR using primer sets and conditions previously described (Bratu et al, 2008;Turton et al, 2006;Woodford et al, 2006). Insertion into the carO gene was screened as described previously (Lee et al, 2011;Lu et al, 2009).…”

Section: Methodsmentioning

confidence: 99%

Diverse carbapenem-resistance mechanisms in 16S rRNA methylase-producing Acinetobacter baumannii

Yamada

Suwabe

2013

Journal of Medical Microbiology

View full text Add to dashboard Cite

show abstract

“…However, carO was not always interrupted in all of our clonally related carbapenem-resistant A. baumannii isolates (29), indicating that a mechanism(s) other than carO disruptions can also account for the reduced carbapenem susceptibility phenotype. In this context, other authors have also reported carO disruptions mediated by various ISs in different carbapenem-resistant A. baumannii clinical isolates obtained in various geographic locations (21,26). In these cases, however, the concomitant overproduction of different carbapenem-hydrolyzing enzymes was considered the main factor responsible for carbapenem resistance (21,26).…”

mentioning

confidence: 95%

Horizontal Gene Transfer and Assortative Recombination within the Acinetobacter baumannii Clinical Population Provide Genetic Diversity at the Single carO Gene, Encoding a Major Outer Membrane Protein Channel

et al. 2011

View full text Add to dashboard Cite

We described previously the presence in Acinetobacter baumannii of a novel outer membrane (OM) protein, CarO, which functions as an L-ornithine OM channel and whose loss was concomitant with increased carbapenem resistance among clonally related nosocomial isolates of this opportunistic pathogen. Here, we describe the existence of extensive genetic diversity at the carO gene within the A. baumannii clinical population. The systematic analysis of carO sequences from A. baumannii isolates obtained from public hospitals in Argentina revealed the existence of four highly polymorphic carO variants among them. Sequence polymorphism between the different A. baumannii CarO variants was concentrated in three well-defined protein regions that superimposed mostly to predicted surface-exposed loops. Polymorphism among A. baumannii CarO variants was manifested in differential electrophoretic mobilities, antigenic properties, abilities to form stable oligomeric structures, and L-ornithine influx abilities through the A. baumannii OM under in vivo conditions. Incongruence between the phylogenies of the clinical A. baumannii isolates analyzed and those of the carO variants they harbor suggests the existence of assortative (entire-gene) carO recombinational exchange within the A. baumannii population. Exchange of carO variants possessing differential characteristics mediated by horizontal gene transfer may constitute an A. baumannii population strategy to survive radically changing environmental conditions, such as the leap from inanimate sources to human hosts and vice versa, persistence in a compromised host, and/or survival in health care facilities.

show abstract

“…Oxa-143 is a class D carbapenemase is similar to OXA-66/OXA-51-like enzyme that contributes to imipenem resistance, which was first reported from Taiwan. Off late, OXA-72 oxacillinase has been also reported in several carbapenem resistant A. baumannii isolates in Taiwan (Lu et al, 2009). …”

Section: D-classmentioning

confidence: 99%

Antibiotic Resistance, Biofilms and Quorum Sensing in Acinetobacter Species

Prashanth¹,

Vasanth²,

Saranathan³

et al. 2012

Antibiotic Resistant Bacteria - A Continuous Challenge in the New Millennium

View full text Add to dashboard Cite

Diversity of carbapenem resistance mechanisms in Acinetobacter baumannii from a Taiwan hospital: spread of plasmid-borne OXA-72 carbapenemase

Abstract: Although diverse mechanisms were identified, production of OXA-72 carbapenemase was the most common mechanism of carbapenem resistance in A. baumannii from this Taiwanese hospital. The plasmidic location of the gene had facilitated its spread to multiple strains.

Cited by 84 publications

References 46 publications

Diverse carbapenem-resistance mechanisms in 16S rRNA methylase-producing Acinetobacter baumannii

Diverse carbapenem-resistance mechanisms in 16S rRNA methylase-producing Acinetobacter baumannii

Horizontal Gene Transfer and Assortative Recombination within the Acinetobacter baumannii Clinical Population Provide Genetic Diversity at the Single carO Gene, Encoding a Major Outer Membrane Protein Channel

Antibiotic Resistance, Biofilms and Quorum Sensing in Acinetobacter Species

Contact Info

Product

Resources

About