Integrons and Gene Cassettes in theEnterobacteriaceae

ABSTRACT Integrons were detected in 59 of 120 (49%) urinary isolates ofEnterobacteriaceae by PCR using degenerate primers targeted to conserved regions of class 1, 2, and 3 integrase genes. PCR sequencing analysis of the cassette arrays revealed a predominance of cassettes that confer resistance to the aminoglycosides and trimethoprim.

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Genetic characterization of multidrug resistance in Shigella spp. from Japan

Journal of Medical Microbiology ◽

10.1099/jmm.0.46725-0 ◽

2006 ◽

Vol 55 (12) ◽

pp. 1685-1691 ◽

Cited By ~ 58

Author(s):

Ashraf M. Ahmed ◽

Kimi Furuta ◽

Kei Shimomura ◽

Yoshio Kasama ◽

Tadashi Shimamoto

Keyword(s):

Shigella Flexneri ◽

Blot Hybridization ◽

Southern Blot Hybridization ◽

Shigella Sonnei ◽

Sequencing Analysis ◽

Class 1 Integron ◽

Gene Cassettes ◽

Class 1 ◽

Shigella Spp

This study characterized the genetic basis of antimicrobial resistance of a number of Shigella spp. isolated from humans from 2000 to 2004 in Hiroshima prefecture, Japan. A total of 26 isolates of Shigella spp. were included in this study. Antimicrobial susceptibility tests revealed high levels of resistance, especially to ampicillin, streptomycin, trimethoprim, tetracycline, nalidixic acid and ciprofloxacin. PCR and DNA sequencing were used for screening and characterization of antibiotic-resistance determinants. PCR sequencing analysis revealed the presence of only one type of class 1 integron in one isolate of Shigella sonnei. This class 1 integron was 1904 bp and contained two gene cassettes: a probable esterase/lipase (estX) and aadA1, which confers resistance to streptomycin and spectinomycin. Two types of class 2 integron were identified in this study. One was the classic type (2158 bp) and carried the three conserved resistance gene cassettes of the class 2 integron, dfrA1, sat1 and aadA1, which confer resistance to trimethoprim, streptothricin and streptomycin/spectinomycin, respectively. This type was detected in both Shigella sonnei (14 isolates) and Shigella flexneri (five isolates). The other type was shorter (1313 bp) and carried only two gene cassettes, dfrA1 and sat1. This integron was detected in a single isolate of Shigella sonnei. PFGE patterns showed limited diversity within clusters of the same species. Furthermore, an extended-spectrum β-lactamase gene, bla OXA-30, which confers resistance to ampicillin, was characterized in all isolates of Shigella flexneri except the oldest strain, which was isolated in 2000. Southern blot hybridization and conjugation experiments showed that bla OXA-30 was located in the chromosome.

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Diversity of gene cassettes and the abundance of the class 1 integron-integrase gene in sediment polluted by metals

Extremophiles ◽

10.1007/s00792-016-0820-3 ◽

2016 ◽

Vol 20 (3) ◽

pp. 283-289 ◽

Cited By ~ 8

Author(s):

Clarisse Oliveira-Pinto ◽

Patrícia S. Costa ◽

Mariana P. Reis ◽

Edmar Chartone-Souza ◽

Andréa M. A. Nascimento

Keyword(s):

Class 1 Integron ◽

Integrase Gene ◽

Gene Cassettes ◽

Class 1

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Antibiotic selective pressure for the maintenance of antibiotic resistant genes in coliform bacteria isolated from the aquatic environment

Water Science & Technology ◽

10.2166/wst.2003.0203 ◽

2003 ◽

Vol 47 (3) ◽

pp. 249-253 ◽

Cited By ~ 18

Author(s):

J.C. Park ◽

J.C. Lee ◽

J.Y. Oh ◽

Y.W. Jeong ◽

J.W. Cho ◽

...

Keyword(s):

Aquatic Environment ◽

Selective Pressure ◽

Functional Class ◽

Coliform Bacteria ◽

Antibiotic Resistant ◽

Gene Cassettes ◽

Class 1 Integrons ◽

Selective Pressures ◽

Class 1 ◽

Inti1 Gene

Coliform bacteria isolated from the aquatic environment were investigated for antibiotic susceptibility and detailed structures of class 1 integrons. A high proportion of isolates were found to be resistant to sulfamethoxazole, aminoglycosides, and β-lactams. The 750 (53.6%) isolates were resistant to one or more of the antibiotics tested out of 1,400 coliform bacteria. Based on the MIC of antibiotics and antibiogram, 150 isolates were selected and further studied for class 1 integrons. The intI1 gene was found in 36 (24.0%) of the 150 isolates. Twelve isolates carried the gene cassettes responsible for antibiotic resistance, while no gene cassettes were found in 24 isolates. Seven different genes, dfrA5, dfrA7, dfrA12, dfrA17, aaA2, aaA5, and aad(3’), were detected in gene cassettes. The dfrA and aad genes located on class 1 integrons were responsible for resistance to trimethoprim and aminoglycosides. The remaining 24 coliform bacteria had the incomplete or non-functional class 1 integrons. These results indicated that antibiotic selective pressures may play an important role to maintain gene cassettes of class 1 integrons and in the absence of sustained antibiotic pressures, such as the aquatic environment, coliform bacteria may carry empty or non-functional class 1 integrons.

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Integron Expression in Multidrug-Resistant Escherichia coli Isolated from House Flies within the Hospital

Walailak Journal of Science and Technology (WJST) ◽

10.48048/wjst.2019.6286 ◽

2018 ◽

Vol 16 (5) ◽

pp. 319-327

Author(s):

Atchariya YOSBOONRUANG ◽

Anong KIDDEE ◽

Chatsuda BOONDUANG ◽

Phannarai PIBALPAKDEE

Keyword(s):

Escherichia Coli ◽

Multidrug Resistance ◽

Antimicrobial Resistance ◽

Hospital Environment ◽

Sequencing Analysis ◽

Class 1 Integron ◽

House Flies ◽

E Coli ◽

Class 1 Integrons ◽

Class 1

Escherichia coli is a serious cause of a variety of hospital-acquired infections and commonly contributes to the environment by house flies. Integrons, particularly class 1 integrons, are the genetic elements that play an important role in the horizontal transfer of antimicrobial resistance mechanism. This mechanism is commonly found in Enterobacteriaceae, especially E. coli. In this study, we aim to investigate the occurrence and antimicrobial resistance patterns of E. coli isolated from the house flies in Phayao hospital and to determine the gene expression of class 1 integrons in those isolates of E. coli. Totally, 70 isolates of E. coli were isolated from 60 house flies collected from the hospital. Fifty-seven of the isolates (81.43 %) were multidrug resistance (MDR) and highly resistant to b-lactams, tetracyclines, and sulfonamides. Of 57 isolates of MDR-E. coli, 20 isolates (35 %) were found to carry class 1 integron genes. Fifteen patterns of antimicrobial resistance occurred in the isolates of integron-positive E. coli. Most integron-positive E. coli isolates were resistant to 7 antimicrobials. Two isolates of these bacteria (10 %) were able to resist 13 out of 14 tested antimicrobials. Using PCR and sequencing analysis, an investigation showed that dfrA17-aadA5, dfrA12-aadA2 gene cassette was the most prevalent cassette (n = 10; 50 %) among the integron-positive E. coli isolates. Our results indicated that the presences of multidrug resistance and class 1 integrons were common in E. coli isolated from the houseflies in hospital. Therefore, screening for integron-positive E. coli from the hospital environment might be necessary for prevention of nosocomial infections.

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Molecular Basis of Sulfonamide and Trimethoprim Resistance in Fish-Pathogenic Aeromonas Isolates

Applied and Environmental Microbiology ◽

10.1128/aem.00560-11 ◽

2011 ◽

Vol 77 (20) ◽

pp. 7147-7150 ◽

Cited By ~ 26

Author(s):

Kristina Kadlec ◽

Ellen von Czapiewski ◽

Heike Kaspar ◽

Jürgen Wallmann ◽

Geovana Brenner Michael ◽

...

Keyword(s):

Resistance Genes ◽

Molecular Basis ◽

Aeromonas Salmonicida ◽

The Novel ◽

Content Type ◽

Gene Cassettes ◽

Class 1 Integrons ◽

Novel Gene ◽

Class 1 ◽

Diseased Fish

ABSTRACTSulfonamide-trimethoprim-resistantAeromonas salmonicidaand motileAeromonasspp. from diseased fish of the GERM-Vet study carried thesul1gene together with mostly cassette-borne trimethoprim resistance genes, including the novel genedfrA28. The sevendfrAanddfrBgenes identified were located mostly in class 1 integrons which commonly harbored other gene cassettes.

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

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-445 ◽

2015 ◽

Vol 78 (8) ◽

pp. 1442-1450 ◽

Cited By ~ 17

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.

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

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.9.3743-3748.2005 ◽

2005 ◽

Vol 49 (9) ◽

pp. 3743-3748 ◽

Cited By ~ 50

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.

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