scholarly journals Molecular Characterization of a Novel Class 1 Integron Containing blaGES-1 and a Fused Product of aac(3)-Ib/aac(6")-Ib" Gene Cassettes in Pseudomonas aeruginosa

2002 ◽  
Vol 46 (3) ◽  
pp. 638-645 ◽  
Author(s):  
Véronique Dubois ◽  
Laurent Poirel ◽  
Caroline Marie ◽  
Corinne Arpin ◽  
Patrice Nordmann ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Diffusion Method ◽  
Fusion Product ◽  
Resistance Pattern ◽  
Clinical Strain ◽  
Homologous Sequence ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Extended Spectrum ◽  
Class 1

ABSTRACT As seen by the disk diffusion method, the clinical strain of Pseudomonas aeruginosa Pa695, resistant to all extended-spectrum cephalosporins and aminoglycosides, exhibited an unusual synergistic effect between ceftazidime and imipenem. This isolate produced an extended-spectrum β-lactamase (ESBL) with a pI of 5.8 that appeared to be chromosomally encoded. Cloning experiments revealed that this ESBL was encoded by bla GES-1, previously described in an integron from Klebsiella pneumoniae. In P. aeruginosa Pa695, a higher level of resistance to ceftazidime than to ticarcillin was observed, and no synergy between the β-lactamase inhibitors and extended-spectrum cephalosporins was detected, in contrast to the resistance pattern observed in K. pneumoniae. Further sequence analysis demonstrated that the bla GES-1 gene cassette was located in a class 1 integron, which contained another sequence corresponding to the fused aac(3)-Ib and aac(6")-Ib" gene cassettes. The fusion product was functional, as was the product of each gene cloned separately: AAC(3)-I, despite the deletion of the four last amino acids, and AAC(6"), which carried three amino acid changes compared with the most homologous sequence. The AAC(3)-I protein conferred an expected gentamicin and fortimicin resistance, and the AAC(6"), despite the Leu-119→Ser substitution, yielded resistance to kanamycin, tobramycin, and dibekacin, but slightly affected netilmicin and amikacin, and had no apparent effect on gentamicin. The fusion product conveyed a large profile of resistance, combining the AAC(6") activity with a higher level of gentamicin resistance without accompanying fortimicin resistance.

scholarly journals Functional and Structural Characterization of the Genetic Environment of an Extended-Spectrum β-Lactamase blaVEB Gene from a Pseudomonas aeruginosa Isolate Obtained in India

2004 ◽  
Vol 48 (9) ◽  
pp. 3284-3290 ◽  
Author(s):  
Daniel Aubert ◽  
Delphine Girlich ◽  
Thierry Naas ◽  
Shanta Nagarajan ◽  
Patrice Nordmann
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Dna Sequences ◽  
Direct Repeat ◽  
Clinical Strain ◽  
Gene Encoding ◽  
Class 1 Integron ◽  
Genetic Environment ◽  
Conserved Sequence ◽  
Extended Spectrum ◽  
Class 1

ABSTRACT A Pseudomonas aeruginosa clinical strain isolated from a patient hospitalized in a New Delhi, India, hospital was resistant to expanded-spectrum cephalosporins, imipenem, and aztreonam. A bla VEB-1-like gene named bla VEB-1a, which codes for the extended-spectrum β-lactamase VEB-1a, was identified. The genetic environment of bla VEB-1a was peculiar: (i) no 5′ conserved sequence (5′-CS) region was present upstream of the β-lactamase gene, whereas bla VEB-1-like genes are usually associated with class 1 integrons; (ii) bla VEB-1a was inserted between two truncated 3′-CS regions in a direct repeat; and (iii) four 135-bp repeated DNA sequences (repeated elements) were located on each side of the bla VEB-1a gene. Expression of the bla VEB-1a gene was driven by a strong promoter located in one of these repeated sequences. In addition, cloning of the β-lactamase content of this P. aeruginosa isolate followed by expression in Escherichia coli identified the naturally occurring AmpC β-lactamase and a gene encoding an OXA-2-like β-lactamase located in a class 1 integron, In78, in which an insertion sequence, ISpa7, was inserted within its 5′-CS region.

Antimicrobial Resistance, Extended-Spectrum β-Lactamase Productivity, and Class 1 Integrons in Escherichia coli from Healthy Swine

2015 ◽  
Vol 78 (8) ◽  
pp. 1442-1450 ◽  
Author(s):  
KANJANA CHANGKAEW ◽  
APIRADEE INTARAPUK ◽  
FUANGFA UTRARACHKIJ ◽  
CHIE NAKAJIMA ◽  
ORASA SUTHIENKUL ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Intestinal Flora ◽  
Class 1 Integron ◽  
Potential Health ◽  
Gene Cassettes ◽  
E Coli ◽  
Class 1 Integrons ◽  
Extended Spectrum ◽  
Class 1

Administration of antimicrobials to food-producing animals increases the risk of higher antimicrobial resistance in the normal intestinal flora of these animals. The present cross-sectional study was conducted to investigate antimicrobial susceptibility and extended-spectrum β-lactamase (ESBL)–producing strains and to characterize class 1 integrons in Escherichia coli in healthy swine in Thailand. All 122 of the tested isolates had drug-resistant phenotypes. High resistance was found to ampicillin (98.4% of isolates), chloramphenicol (95.9%), gentamicin (78.7%), streptomycin (77.9%), tetracycline (74.6%), and cefotaxime (72.1%). Fifty-four (44.3%) of the E. coli isolates were confirmed as ESBL-producing strains. Among them, blaCTX-M (45 isolates) and blaTEM (41 isolates) were detected. Of the blaCTX-M-positive E. coli isolates, 37 carried the blaCTX-M-1 cluster, 12 carried the blaCTX-M-9 cluster, and 5 carried both clusters. Sequence analysis revealed blaTEM-1, blaTEM-135, and blaTEM-175 in 38, 2, and 1 isolate, respectively. Eighty-seven (71%) of the 122isolates carried class 1 integrons, and eight distinct drug-resistance gene cassettes with seven different integron profiles were identified in 43 of these isolates. Gene cassettes were associated with resistance to aminoglycosides (aadA1, aadA2, aadA22, or aadA23), trimethoprim (dfrA5, dfrA12, or dfrA17), and lincosamide (linF). Genes encoding β-lactamases were not found in class 1 integrons. This study is the first to report ESBL-producing E. coli with a class 1 integron carrying the linF gene cassette in swine in Thailand. Our findings confirm that swine can be a reservoir of ESBL-producing E. coli harboring class 1 integrons, which may become a potential health risk if these integrons are transmitted to humans. Intensive analyses of animal, human, and environmental isolates are needed to control the spread of ESBL-producing E. coli strains.

scholarly journals BEL-1, a Novel Clavulanic Acid-Inhibited Extended-Spectrum β-Lactamase, and the Class 1 Integron In120 in Pseudomonas aeruginosa

2005 ◽  
Vol 49 (9) ◽  
pp. 3743-3748 ◽  
Author(s):  
Laurent Poirel ◽  
Laura Brinas ◽  
Annemie Verlinde ◽  
Louis Ide ◽  
Patrice Nordmann
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Clavulanic Acid ◽  
Cloning And Sequencing ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Esbl Gene ◽  
Class A ◽  
Class 1 ◽  
Synergy Test ◽  
Specific Sequences

ABSTRACT Screening by a double-disk synergy test identified a Pseudomonas aeruginosa isolate that produced a clavulanic acid-inhibited expanded-spectrum β-lactamase (ESBL). Cloning and sequencing identified a novel ESBL, BEL-1, weakly related to other Ambler class A ESBLs. β-Lactamase BEL-1 hydrolyzed significantly most expanded-spectrum cephalosporins and aztreonam, and its activity was inhibited by clavulanic acid, tazobactam, cefoxitin, moxalactam, and imipenem. This chromosome-encoded ESBL gene was embedded in a class 1 integron containing three other gene cassettes. In addition, this integron was bracketed by Tn1404 transposon sequences at its right end and by P. aeruginosa-specific sequences at its left end.

scholarly journals The aadB Gene Cassette Is Associated with blaSHV Genes in Klebsiella Species Producing Extended-Spectrum β-Lactamases

2005 ◽  
Vol 49 (2) ◽  
pp. 794-797 ◽  
Author(s):  
Louisa A. Jones ◽  
Christopher J. McIver ◽  
Mi-Jurng Kim ◽  
William D. Rawlinson ◽  
Peter A. White
Keyword(s):  
Gene Cassette ◽  
Amplicon Sequencing ◽  
Klebsiella Species ◽  
Class 1 Integron ◽  
Beta Lactamases ◽  
Gene Cassettes ◽  
Extended Spectrum ◽  
Class 1 ◽  
Extended Spectrum Beta Lactamases

ABSTRACT Integrons were detected in 37 (72.5%) of 51 Klebsiella spp. producing extended-spectrum beta-lactamases by PCR with primers that targeted integrase genes and cassette regions. PCR and amplicon sequencing of the cassette regions revealed aadB and aadA2 gene cassettes that confer resistance to a range of aminoglycosides. aadB was associated with a class 1 integron on a 28-kb plasmid, pES1, that also contained bla SHV-12 and IS26.

scholarly journals Novel Variant (blaVIM-4) of the Metallo-β-Lactamase Gene blaVIM-1 in a Clinical Strain of Pseudomonas aeruginosa

2002 ◽  
Vol 46 (12) ◽  
pp. 4026-4028 ◽  
Author(s):  
Spyros Pournaras ◽  
Athanassios Tsakris ◽  
Maria Maniati ◽  
Leonidas S. Tzouvelekis ◽  
Antonios N. Maniatis
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Amino Acid Position ◽  
Clinical Strain ◽  
Nucleotide Difference ◽  
Class 1 Integron ◽  
Class 1 ◽  
Novel Variant ◽  
Lactamase Gene

ABSTRACT A Pseudomonas aeruginosa isolate highly resistant to carbapenems was collected from a patient with postsurgical cerebrospinal infection in Greece. The isolate carried a class 1 integron that contained as a sole cassette the gene bla VIM-4, a novel variant of bla VIM-1, with one nucleotide difference resulting in a Ser-to-Arg change at amino acid position 175 of the VIM-1 enzyme. This is the first detection of a VIM-1 variant after its appearance in Italy.

scholarly journals Complex Genetic Structures with Repeated Elements, a sul-Type Class 1 Integron, and the blaVEB Extended-Spectrum β-Lactamase Gene

2006 ◽  
Vol 50 (5) ◽  
pp. 1745-1752 ◽  
Author(s):  
Thierry Naas ◽  
Daniel Aubert ◽  
Thierry Lambert ◽  
Patrice Nordmann
Keyword(s):  
Direct Repeat ◽  
Aminoglycoside Resistance ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Conserved Sequence ◽  
Extended Spectrum ◽  
Class 1 ◽  
Genetic Structures ◽  
Lactamase Gene ◽  
First Time

ABSTRACT Two clinical isolates of Pseudomonas aeruginosa, TL-1 and TL-2, were isolated from a patient transferred from Bangladesh and hospitalized for osteomyelitis in Paris, France. P. aeruginosa TL-1 expressed the extended-spectrum β-lactamase VEB-1a and was susceptible only to imipenem and colistin, while P. aeruginosa TL-2 expressed only the naturally occurring bla AmpC gene at a basal level and exhibited a wild-type β-lactam resistance phenotype. In TL-1, the typical 5′-end conserved sequence (5′-CS) region of class 1 integrons usually present upstream of the bla VEB-1a gene was replaced by a truncated 3′-CS and a 135-bp repeated element (Re). Downstream of the bla VEB-1a gene, an insertion sequence, ISPa31 disrupted by ISPa30, and an orf513 sequence, belonging to a common region (conserved region 1 [CR1]) immediately upstream of the aphA-6 gene, were present. Further downstream, a second truncated 3′-CS region in direct repeat belonged to In51, an integron containing two gene cassettes (aadA6 and the OrfD cassette). Thus, the overall structure corresponded to a sul-type class 1 integron termed In121. Genetic analyses revealed that both isolates were clonally related and differed by a ca. 100-kb fragment that contained In121. Both isolates contained another integron, In122, that carried three gene cassettes: aadB, dfrA1, and the OrfX cassette. This work identifies for the first time the spread of Re-associated bla VEB genes located on a sul-type integron. It also reports for the first time a CR1 element in P. aeruginosa that is associated with an aminoglycoside resistance aphA-6 gene that is expressed from a composite promoter.

scholarly journals Class 1 Integron Containing a New Gene Cassette, aadA10, Associated with Tn1404 from R151

2002 ◽  
Vol 46 (8) ◽  
pp. 2400-2408 ◽  
Author(s):  
Sally R. Partridge ◽  
Christina M. Collis ◽  
Ruth M. Hall
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Gene Cassette ◽  
Class 1 Integron ◽  
Gene Cassettes ◽  
Base Element ◽  
Class 1 Integrons ◽  
Resistance Determinants ◽  
Class 1 ◽  
New Gene

ABSTRACT The carbenicillin, gentamicin, kanamycin, streptomycin, spectinomycin, sulfonamide, and tobramycin resistance determinants found on Pseudomonas aeruginosa plasmid R151 have previously been shown to translocate to another plasmid, R388, and it was inferred that a transposon, Tn1404, carried the resistance determinants. Sequencing of the cassette array from the plasmid known as R388::Tn1404 revealed two known gene cassettes, oxa10 and aadB, and a previously unidentified cassette determining resistance to streptomycin and spectinomycin, here designated aadA10, in the order oxa10-aadB-aadA10. These cassettes replaced the dfrB2-orfA cassette array of R388, indicating that movement of the resistance determinants from R151 to R388 resulted from recombinational exchange between two class 1 integrons rather than transposition. The AadA10 protein is most closely related to AadA6 (85% identical) and AadA7 (80% identical). The aadA10 cassette found here has only a simple site containing a 7-bp spacer derived from attI1 in place of a 59-base element and is likely to represent a derivative of the complete cassette. IntI1-mediated deletion of the aadA10 cassette was not detected, indicating that this single simple site is either inactive or only weakly active.

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