Plasmid-mediated beta-lactamases in clinical isolates of Klebsiella pneumoniae and Escherichia coli resistant to ceftazidime

Vuye, A; Verschraegen, Gerda; Claeys, Geert

doi:10.1128/aac.33.5.757

Cited by 39 publications

(12 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, soon after the introduction of the newer extended-spectrum cephalosporins into clinical practice, the emergence of resistance with subsequent therapeutic failures was observed. Extended-spectrum enzymes were first recognized in Europe in 1983 [22], but have since been reported in many countries [7,8,[22][23][24][25][26][27]. The prevalence of strains producing extended-spectrum b-lactamases is increasing worldwide, and K. pneumoniae is by far the most common species in which these enzymes have been recognized.…”

Section: Discussionmentioning

confidence: 99%

Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

Galani

Xirouchaki

Kanellakopoulou

et al. 2002

Clinical Microbiology and Infection

View full text Add to dashboard Cite

show abstract

Section: Discussionmentioning

confidence: 99%

Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

Galani

Xirouchaki

Kanellakopoulou

et al. 2002

Clinical Microbiology and Infection

View full text Add to dashboard Cite

show abstract

“…Evidence has been provided for successive isolation, from the same patient, of a strain with an increased resistance toward broad-spectrum cephalosporins that correlated with a change in the pI of the TEM enzyme involved (35). In addition, variants with several mutations are rare and apparently remain confined to their site of isolation: TEM-9 in Great Britain, TEM-11 in Belgium, and TEM-14 and TEM-15 in France.…”

Section: Discussionmentioning

confidence: 99%

Development of "oligotyping" for characterization and molecular epidemiology of TEM beta-lactamases in members of the family Enterobacteriaceae

Mabilat

Courvalin

1990

Antimicrob Agents Chemother

155

111

View full text Add to dashboard Cite

Based on the DNA sequences of bla EM and blaTEMZ, which encode parental penicillinases TEM-1 and TEM-2, respectively, and of blaTEM3, blaTEM-4 blaTEMS, blaTEM46, and blaTEM-79 which encode extendedspectrum 3-lactamases, we designed heptadecanucleotides to discriminate point mutations in five loci. Determination of the hybridization profiles by colony hybridization with this selection of probes, termed "oligotyping," allowed characterization of the TEM variants present in 265 clinical isolates of the family Enterobacteriaceae that exhibit synergism between a peniciflinase inhibitor and broad-spectrum cephalosporins. Among the 222 strains harboring TEM enzymes, Klebsiella pneumoniae (48%) and Escherichia coli (21%) were predominant, and TEM-3 was the most common enzyme (60%). Penicillinases TEM-1 and TEM-2 were detected alone (15 and 1%, respectively), combined (1%), or associated with another TEM P-lactamase (17 and 6%, respectively). Fourteen variants, including seven new enzymes, were detected. One, TEM-13, was a new penicillinase with the same isoelectric point and substrate range as TEM-2 but differed by a single amino acid substitution, whereas the others, TEM-14 to TEM-19, were extended-spectrum ,I-lactamases that consisted of novel combinations of known amino acid substitutions. Different TEM variants were found to coexist within the same cells. A patient could harbor two or three different strains that encoded the same enzyme or two indistinguishable isolates that produced distinct TEM 13-lactamases.3-Lactams constitute one of the most important families of antibiotics, but resistance to these drugs has emerged following their wide use in therapy. Gram-negative bacteria are most often resistant as a result of their production of ,B-lactamases (17), and numerous enzymes that differ in their substrate ranges have been described (34). The utilization of 3-lactams resistant to hydrolysis by penicillinases, such as broad-spectrum cephalosporins, led to the selection of new enzymes. In 1983, 5 years after the introduction of this class of drugs in Europe, Knothe et al. (13) reported transferable resistance to cefotaxime in clinical isolates of Klebsiella pneumoniae and Serratia marcescens. Biochemical and DNA-DNA hybridization studies (12) indicated that the enzyme responsible for this new resistance phenotype was closely related to SHV-1 penicillinase and was designated SHV-2. Starting in 1984, nosocomial outbreaks of multiresistant members of the family Enterobacteriaceae highly resistant to cefotaxime and ceftazidime occurred in French hospitals (4,11,27,28). Resistance was due to a new, plasmid-mediated, extended-spectrum ,B-lactamase named CTX-1 (27). Molecular analysis (30) and nucleotide sequence determination (29) of blaTEM-3, the structural gene for the enzyme, indicated that the P-lactamase was a double point mutation of TEM-2 penicillinase and was therefore redesignated TEM-3 (30). Since then, similar enzymes of either the SHV type (5, 9) or the TEM type (3,8,22,24)

show abstract

“…sedlakii 2596, which produces the chromosomally encoded class A ␤-lactamase Sed-1, was resistant to aminopenicillins, carboxypenicillins, and early cephalosporins but not to acylureidopenicillins such as piperacillin. This resistance profile can be readily explained by the hydrolytic properties of Sed-1 (high catalytic efficiency against benzylpenicillin, clox-acillin, and early cephalosporins such as cephalothin and cefuroxime, but low efficiency for piperacillin), which closely resemble those of the cefuroximases, such as the chromosomeencoded ␤-lactamase CUM from P. vulgaris or the plasmidencoded ␤-lactamases FEC-1, FPM-1, and FUR from E. coli, Proteus mirabilis, and Klebsiella pneumoniae, respectively (36,45,58,59). Cefotaxime, cefpirome, and aztreonam were also hydrolyzed by Sed-1 but with low catalytic efficiencies and moderate apparent affinities (Table 4).…”

Section: Discussionmentioning

confidence: 99%

Novel Class A β-Lactamase Sed-1 from Citrobacter sedlakii : Genetic Diversity of β-Lactamases within the Citrobacter Genus

Pétrella¹,

Clermont

Casin

et al. 2001

Antimicrob Agents Chemother

View full text Add to dashboard Cite

Citrobacter sedlakii 2596, a clinical strain resistant to aminopenicillins, carboxypenicillins, and early cephalosporins such as cephalothin, but remaining susceptible to acylureidopenicillins, carbapenems, and later cephalosporins such as cefotaxime, was isolated from the bile of a patient treated with ␤-lactam and quinolone antibiotics. The isolate produced an inducible class A ␤-lactamase of pI 8.6, named Sed-1, which was purified. Characterized by a molecular mass of 30 kDa, Sed-1 preferentially hydrolyzed benzylpenicillin, cephalothin, and cloxacillin. The corresponding gene, bla Sed-1 , was cloned and sequenced. Its deduced amino acid sequence shared more than 60% identity with the chromosome-encoded ␤-lactamases from Citrobacter koseri (formerly C. diversus) (84%), Klebsiella oxytoca (74%), Serratia fonticola (67%), and Proteus vulgaris (63%) and 71% identity with the plasmid-mediated enzyme MEN-1. A gene coding for a LysR transcriptional regulator was found upstream from bla Sed-1 . This regulator, named SedR, displayed 90% identity with the AmpR sequence of the chromosomal ␤-lactamase from C. koseri and 63 and 50% identity with the AmpR sequences of P. vulgaris and Enterobacter cloacae, respectively. By using DNA-DNA hybridization, a bla Sed-1 -like gene was identified in two reference strains, C. sedlakii (CIP-105037) and Citrobacter rodentium (CIP-104675), but not in the 18 strains of C. koseri studied. Two DNA fragments were amplified and sequenced from the reference strains of C. sedlakii CIP-105037 and C. rodentium CIP-104675 using two primers specific for bla Sed-1 . They shared 98 and 80% identity with bla Sed-1 , respectively, confirming the diversity of the chromosomally encoded class A ␤-lactamases found in Citrobacter.

show abstract

Plasmid-mediated beta-lactamases in clinical isolates of Klebsiella pneumoniae and Escherichia coli resistant to ceftazidime

Cited by 39 publications

References 23 publications

Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

Transferable plasmid mediating resistance to multiple antimicrobial agents in Klebsiella pneumoniae isolates in Greece

Development of "oligotyping" for characterization and molecular epidemiology of TEM beta-lactamases in members of the family Enterobacteriaceae

Novel Class A β-Lactamase Sed-1 from Citrobacter sedlakii : Genetic Diversity of β-Lactamases within the Citrobacter Genus

Contact Info

Product

Resources

About