scholarly journals GES-13, a β-Lactamase Variant Possessing Lys-104 and Asn-170 in Pseudomonas aeruginosa

2010 ◽  
Vol 54 (3) ◽  
pp. 1331-1333 ◽  
Author(s):  
S. D. Kotsakis ◽  
C. C. Papagiannitsis ◽  
E. Tzelepi ◽  
N. J. Legakis ◽  
V. Miriagou ◽  
...  

ABSTRACT GES-13 β-lactamase, a novel GES variant possessing Lys-104 and Asn-170, was identified in Pseudomonas aeruginosa. bla GES-13 was the single gene cassette of a class 1 integron probably located in the chromosome. GES-13 efficiently hydrolyzed broad-spectrum cephalosporins and aztreonam. Imipenem was a potent inhibitor of GES-13 but was not hydrolyzed at measurable rates.

2005 ◽  
Vol 49 (10) ◽  
pp. 4400-4403 ◽  
Author(s):  
Gulcin G. Gacar ◽  
Kenan Midilli ◽  
Fetiye Kolayli ◽  
Kivanc Ergen ◽  
Sibel Gundes ◽  
...  

ABSTRACT A VIM-5-producing Enterobacter cloacae isolate (EDV/1) was identified in a collection of clinical strains stored before 2002. The gene, bla VIM-5, was located on a 2,712-bp BamHI-HindIII fragment of a 23-kbp (approximately) nonconjugative plasmid (pEDV5) in a class 1 integron as a single gene cassette.


2002 ◽  
Vol 46 (8) ◽  
pp. 2400-2408 ◽  
Author(s):  
Sally R. Partridge ◽  
Christina M. Collis ◽  
Ruth M. Hall

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.


2008 ◽  
Vol 52 (8) ◽  
pp. 2943-2946 ◽  
Author(s):  
U. Garza-Ramos ◽  
R. Morfin-Otero ◽  
H. S. Sader ◽  
R. N. Jones ◽  
E. Hernández ◽  
...  

ABSTRACT During 2003, 40 carbapenem-resistant Pseudomonas aeruginosa clinical isolates collected in a Mexican tertiary-care hospital were screened for metallo-β-lactamase production. Thirteen isolates produced IMP-15, and 12 had a single pulsed-field gel electrophoresis pattern. The bla IMP-15 gene cassette was inserted in a plasmid-borne integron with a unique array of gene cassettes and was named In95.


2016 ◽  
Vol 61 (3) ◽  
Author(s):  
Costas C. Papagiannitsis ◽  
Leonidas S. Tzouvelekis ◽  
Eva Tzelepi ◽  
Vivi Miriagou

ABSTRACT By searching the Integrall integron and GenBank databases, a novel open reading frame (ORF) of 51 nucleotides (nts) (ORF-17) overlapping the previously described ORF-11 was identified within the attI1 site in virtually all class 1 integrons. Using a set of isogenic plasmid constructs carrying a single gene cassette (bla GES-1) and possessing a canonical translation initiation region, we found that ORF-17 contributes to GES-1 expression.


2001 ◽  
Vol 45 (2) ◽  
pp. 546-552 ◽  
Author(s):  
Laurent Poirel ◽  
Thierry Lambert ◽  
Salih Türkoglü ◽  
Esthel Ronco ◽  
Jean-Louis Gaillard ◽  
...  

ABSTRACT Two clonally unrelated Pseudomonas aeruginosa clinical strains, RON-1 and RON-2, were isolated in 1997 and 1998 from patients hospitalized in a suburb of Paris, France. Both isolates expressed the class B carbapenem-hydrolyzing β-lactamase VIM-2 previously identified in Marseilles in the French Riviera. In both isolates, thebla VIM-2 cassette was part of a class 1 integron that also encoded aminoglycoside-modifying enzymes. In one case, two novel aminoglycoside resistance gene cassettes,aacA29a and aacA29b, were located at the 5′ and 3′ end of the bla VIM-2 gene cassette, respectively. The aacA29a and aacA29b gene cassettes were fused upstream with a 101-bp part of the 5′ end of theqacE cassette. The deduced amino acid sequence AAC(6′)-29a protein shared 96% identity with AAC(6′)-29b but only 34% identity with the aacA7-encoded AAC(6′)-I1, the closest relative of the AAC(6′)-I family enzymes. These aminoglycoside acetyltransferases had amino acid sequences much shorter (131 amino acids) than the other AAC(6′)-I enzymes (144 to 153 amino acids). They conferred resistance to amikacin, isepamicin, kanamycin, and tobramycin but not to gentamicin, netilmicin, and sisomicin.


Author(s):  
M Ishrat Jahan ◽  
M Mizanur Rahaman ◽  
M Anwar Hossain ◽  
Munawar Sultana

Abstract Objectives Emergence of carbapenem-resistant Pseudomonas aeruginosa is limiting current treatment options. Carbapenemases and their association with integrons can cause rapid dissemination of resistance traits. We report here the co-existence and chromosomal inheritance of all four classes of β-lactamase and the presence of a unique class 1 integron (intI1) harbouring blaVIM-5 within a single isolate of P. aeruginosa, DMC-27b. Methods DMC-27b, isolated from urine, was characterized for carbapenem resistance both phenotypically and genotypically. The orientation of gene cassette structures of class 1 integrons was determined using referenced and designed overlapping primers and complete genome sequence (CGS) data. The antimicrobial resistance profile, porin protein mutations and the presence of active efflux activity were studied from the CGS. Results P. aeruginosa DMC-27b was resistant to a total of 20 antibiotics, with imipenem and meropenem MIC90s of >512 mg/L. The isolate harboured all four classes of β-lactamase: VEB-1 (class A), VIM-5 (class B), PDC-35 (class C) and OXA-2 and OXA-50 (both class D). Chromosomal harbouring of blaVIM-5 was associated with the intI1 gene cassette as the sole gene, a unique cassette so far reported. A total of 11 mutations, among them some mutations causing extra folds and changes in binding sites, in porin protein OprD might also affect its functionality regarding the transportation of antibiotics. Conclusions This is one of the earliest reports of its kind on the co-existence of all four β-lactamase classes in P. aeruginosa DMC-27b. Acquisition of multiple resistance determinants is paving the way for the development of MDR. This superbug is a model for rapid dissemination of resistance traits both horizontally and vertically.


2005 ◽  
Vol 49 (9) ◽  
pp. 3734-3742 ◽  
Author(s):  
Jun-ichiro Sekiguchi ◽  
Tsukasa Asagi ◽  
Tohru Miyoshi-Akiyama ◽  
Tomoko Fujino ◽  
Intetsu Kobayashi ◽  
...  

ABSTRACT We characterized multidrug-resistant Pseudomonas aeruginosa strains isolated from patients involved in an outbreak of catheter-associated urinary tract infections that occurred in a neurosurgery ward of a hospital in Sendai, Japan. Pulsed-field gel electrophoresis of SpeI-, XbaI-, or HpaI-digested genomic DNAs from the isolates revealed that clonal expansion of a P. aeruginosa strain designated IMCJ2.S1 had occurred in the ward. This strain possessed broad-spectrum resistance to aminoglycosides, β-lactams, fluoroquinolones, tetracyclines, sulfonamides, and chlorhexidine. Strain IMCJ2.S1 showed a level of resistance to some kinds of disinfectants similar to that of a control strain of P. aeruginosa, ATCC 27853. IMCJ2.S1 contained a novel class 1 integron, In113, in the chromosome but not on a plasmid. In113 contains an array of three gene cassettes of bla IMP-1, a novel aminoglycoside resistance gene, and the aadA1 gene. The aminoglycoside resistance gene, designated aac(6′)-Iae, encoded a 183-amino-acid protein that shared 57.1% identity with AAC(6′)-Iq. Recombinant AAC(6′)-Iae protein showed aminoglycoside 6′-N-acetyltransferase activity by thin-layer chromatography. Escherichia coli expressing exogenous aac(6′)-Iae showed resistance to amikacin, dibekacin, isepamicin, kanamycin, netilmicin, sisomicin, and tobramycin but not to arbekacin, gentamicins, or streptomycin. Alterations of gyrA and parC at the amino acid sequence level were detected in IMCJ2.S1, suggesting that such mutations confer the resistance to fluoroquinolones observed for this strain. These results indicate that P. aeruginosa IMCJ2.S1 has developed multidrug resistance by acquiring resistance determinants, including a novel member of the aac(6′)-I family and mutations in drug resistance genes.


2002 ◽  
Vol 46 (2) ◽  
pp. 566-569 ◽  
Author(s):  
Laurent Poirel ◽  
Patrick Gerome ◽  
Christophe De Champs ◽  
Jean Stephanazzi ◽  
Thierry Naas ◽  
...  

ABSTRACT Pseudomonas aeruginosa clinical isolate CY-1, which was resistant to ceftazidime, harbored a conjugative ca. 250-kb plasmid that contained a class 1 integron with two gene cassettes encoding OXA-32, an OXA-2- type β-lactamase, and the aminoglycoside acetyltransferase AAC(6′)Ib9. OXA-32 differed from OXA-2 by an Leu169Ile amino acid substitution (class D numbering). Site-directed mutagenesis established that Ile169 is responsible for resistance to ceftazidime but not to cefotaxime.


2001 ◽  
Vol 45 (2) ◽  
pp. 447-453 ◽  
Author(s):  
Laurent Poirel ◽  
Delphine Girlich ◽  
Thierry Naas ◽  
Patrice Nordmann

ABSTRACT Pseudomonas aeruginosa ED-1, isolated from a pulmonary brush of a patient hospitalized in a suburb of Paris, France, was resistant to ceftazidime and of intermediate susceptibility to ureidopenicillins and to cefotaxime. Cloning and expression of the β-lactamase gene content of this isolate in Escherichia coli DH10B identified a novel OXA-10 variant, OXA-28, with a pI value of 8.1 and a molecular mass of 29 kDa. It differed from OXA-10 by 10 amino acid changes and from OXA-13 and OXA-19 by 2 amino acid changes, including a glycine instead of tryptophan at position 164, which is likely involved in its resistance to ceftazidime. Like OXA-11, -14, -16, and -19 and as opposed to OXA-17, OXA-28 predominantly compromised ceftazidime and had only marginal effect on the MICs of aztreonam and cefotaxime in P. aeruginosa. Once expressed in E. coli, OXA-28 raised the MIC of ceftazidime to a much higher level than those of amoxicillin, cephalothin, and cefotaxime (128, 16, 8, and 4 μg/ml, respectively). OXA-28 β-lactamase had a broad spectrum of activity, including ceftazidime. Its activity was partially antagonized by clavulanic acid (50% inhibitory concentration, 10 μM) and NaCl addition. The oxa28 gene cassette was inserted in the variable region of a class 1 integron, In57, immediately downstream of an amino 6′-N-acetyltransferase gene cassette,aac(6′)Ib. The structures of the integrons carrying eitheroxa28, oxa13, or oxa19 gene cassettes were almost identical, suggesting that they may have derived from a common ancestor as a result of the common European origin of theP. aeruginosa isolates. In57 was located on a self-transferable plasmid of ca. 150 kb that was transferred fromP. aeruginosa to P. aeruginosa.


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