scholarly journals blaCTX-M-2 and blaCTX-M-28 extended-spectrum β-lactamase genes and class 1 integrons in clinical isolates of Klebsiella pneumoniae from Brazil

2010 ◽  
Vol 105 (2) ◽  
pp. 163-167 ◽  
Author(s):  
Ana Catarina S Lopes ◽  
Dyana Leal Veras ◽  
Alexsandra Mariá S Lima ◽  
Rita de Cássia Andrade Melo ◽  
Juan Ayala
2006 ◽  
Vol 50 (12) ◽  
pp. 4198-4201 ◽  
Author(s):  
Sonia Ktari ◽  
Guillaume Arlet ◽  
Basma Mnif ◽  
Valérie Gautier ◽  
Fouzia Mahjoubi ◽  
...  

ABSTRACT Klebsiella pneumoniae clinical isolates resistant to carbapenems were recovered from 11 patients in the hospital of Sfax, Tunisia. The isolates were closely related as shown by pulsed-field gel electrophoresis, and they produced VIM-4 metallo-enzyme, CTX-M-15 extended-spectrum β-lactamase, and CMY-4 AmpC enzyme. The bla VIM-4 gene is part of a class 1 integron.


2015 ◽  
Vol 78 (8) ◽  
pp. 1442-1450 ◽  
Author(s):  
KANJANA CHANGKAEW ◽  
APIRADEE INTARAPUK ◽  
FUANGFA UTRARACHKIJ ◽  
CHIE NAKAJIMA ◽  
ORASA SUTHIENKUL ◽  
...  

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.


2011 ◽  
Vol 55 (9) ◽  
pp. 4267-4276 ◽  
Author(s):  
Vinod Kumar ◽  
Peng Sun ◽  
Jessica Vamathevan ◽  
Yong Li ◽  
Karen Ingraham ◽  
...  

ABSTRACTThere is a global emergence of multidrug-resistant (MDR) strains ofKlebsiella pneumoniae, a Gram-negative enteric bacterium that causes nosocomial and urinary tract infections. While the epidemiology ofK. pneumoniaestrains and occurrences of specific antibiotic resistance genes, such as plasmid-borne extended-spectrum β-lactamases (ESBLs), have been extensively studied, only four complete genomes ofK. pneumoniaeare available. To better understand the multidrug resistance factors inK. pneumoniae, we determined by pyrosequencing the nearly complete genome DNA sequences of two strains with disparate antibiotic resistance profiles, broadly drug-susceptible strain JH1 and strain 1162281, which is resistant to multiple clinically used antibiotics, including extended-spectrum β-lactams, fluoroquinolones, aminoglycosides, trimethoprim, and sulfamethoxazoles. Comparative genomic analysis of JH1, 1162281, and other publishedK. pneumoniaegenomes revealed a core set of 3,631 conserved orthologous proteins, which were used for reconstruction of whole-genome phylogenetic trees. The close evolutionary relationship between JH1 and 1162281 relative to otherK. pneumoniaestrains suggests that a large component of the genetic and phenotypic diversity of clinical isolates is due to horizontal gene transfer. Using curated lists of over 400 antibiotic resistance genes, we identified all of the elements that differentiated the antibiotic profile of MDR strain 1162281 from that of susceptible strain JH1, such as the presence of additional efflux pumps, ESBLs, and multiple mechanisms of fluoroquinolone resistance. Our study adds new and significant DNA sequence data onK. pneumoniaestrains and demonstrates the value of whole-genome sequencing in characterizing multidrug resistance in clinical isolates.


2021 ◽  
Vol 55 (1 (254)) ◽  
pp. 58-66
Author(s):  
Magdalina K. Zakharyan

A total of 182 non-typhoid Salmonella enterica (NTS) isolates recovered from patients between 1996 and 2014 were included in the current study focused on class 1 integron detection and its association with multidrug resistance (MDR) phenotype. A high prevalence of isolates displaying MDR and penta-resistance (resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide, tetracycline) phenotypes of clinical significance was revealed. Serotype-specific prevalence of antimicrobial resistance as well as class 1 integrons and inserted variable segments was detected in isolates. The results indicated the limitations of current antimicrobial therapy to control infections caused by MDR isolates of NTS, especially belonging to serotype Typhimurium.


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