Characterization of class 1 integrons-mediated antibiotic resistance among calf pathogenic Escherichia coli

ABSTRACT A total of 50 isolates of Shiga toxin-producing Escherichia coli (STEC), including 29 O157:H7 and 21 non-O157 STEC strains, were analyzed for antimicrobial susceptibilities and the presence of class 1 integrons. Seventy-eight (n = 39) percent of the isolates exhibited resistance to two or more antimicrobial classes. Multiple resistance to streptomycin, sulfamethoxazole, and tetracycline was most often observed. Class 1 integrons were identified among nine STEC isolates, including serotypes O157:H7, O111:H11, O111:H8, O111:NM, O103:H2, O45:H2, O26:H11, and O5:NM. The majority of the amplified integron fragments were 1 kb in size with the exception of one E. coli O111:H8 isolate which possessed a 2-kb amplicon. DNA sequence analysis revealed that the integrons identified within the O111:H11, O111:NM, O45:H2, and O26:H11 isolates contained the aadA gene encoding resistance to streptomycin and spectinomycin. Integrons identified among the O157:H7 and O103:H2 isolates also possessed a similaraadA gene. However, DNA sequencing revealed only 86 and 88% homology, respectively. The 2-kb integron of the E. coli O111:H8 isolate contained three genes, dfrXII,aadA2, and a gene of unknown function, orfF, which were 86, 100, and 100% homologous, respectively, to previously reported gene cassettes identified in integrons found inCitrobacter freundii and Klebsiella pneumoniae. Furthermore, integrons identified among the O157:H7 and O111:NM strains were transferable via conjugation to another strain of E. coli O157:H7 and to several strains of Hafnia alvei. To our knowledge, this is the first report of integrons and antibiotic resistance gene cassettes in STEC, in particular E. coliO157:H7.

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Occurrence and characterization of class 1 integrons in Escherichia coli from healthy individuals and those with urinary infection

Journal of Medical Microbiology ◽

10.1099/jmm.0.000468 ◽

2017 ◽

Vol 66 (5) ◽

pp. 577-583 ◽

Cited By ~ 14

Author(s):

Clarisse Oliveira-Pinto ◽

Cristiane Diamantino ◽

Patrícia L Oliveira ◽

Mariana P Reis ◽

Patrícia S Costa ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Infection ◽

Healthy Individuals ◽

Class 1 Integrons ◽

Class 1

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Antibiotic Resistance and Characteristics of Integrons in Escherichia coli Isolated from Penaeus vannamei at a Freshwater Shrimp Farm in Zhejiang Province, China

Journal of Food Protection ◽

10.4315/0362-028x.jfp-18-444 ◽

2019 ◽

Vol 82 (3) ◽

pp. 470-478 ◽

Cited By ~ 6

Author(s):

HUI CHENG ◽

HAN JIANG ◽

JIEHONG FANG ◽

CHENG ZHU

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Insertion Sequence ◽

Zhejiang Province ◽

Resistant Bacteria ◽

Penaeus Vannamei ◽

Shrimp Farm ◽

E Coli ◽

Class 1 Integrons ◽

Class 1

ABSTRACT Our study was conducted to investigate the antibiotic susceptibility profiles, integrons and their associated gene cassettes (GCs), and insertion sequence common regions of Escherichia coli isolates from Penaeus vannamei collected at a large-scale freshwater shrimp farm in Zhejiang Province, People's Republic of China. A total of 182 E. coli isolates were identified from 200 samples. With the exception of imipenem, isolates were most commonly resistant to β-lactams, followed by tetracylines and sulfonamides. Fifty-two (28.6%) E. coli isolates were classified as multidrug resistant, and the patterns were highly diverse, with 29 types represented. The multiple-antibiotic resistance indices of the isolates were 0.17 to 0.56; 9.3% (17) of the 182 isolates were positive for class 1 integrons, 0.5% (1 isolate) was positive for class 2 integrons, and an insertion sequence common region 1 element was found upstream of the intI1 (integrase) gene in one of the intI1-positive isolates. Four GC arrays were detected in class 1 integrons, and one GC array was detected in class 2 integrons. Although the overall prevalence of antimicrobial-resistant bacteria in P. vannamei was lower than that previously reported for poultry and livestock farms in China, concerns about the inappropriate use of antibiotics and the transmission of antimicrobial-resistant bacteria in aquaculture were raised. Alternative approaches to reducing or replacing the use of antibiotics should be further studied.

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Antimicrobial Resistance and Class 1 Integrons in Pathogenic Escherichia coli from Dairy Farms

Foodborne Pathogens and Disease ◽

10.1089/fpd.2005.2.348 ◽

2005 ◽

Vol 2 (4) ◽

pp. 348-352 ◽

Cited By ~ 20

Author(s):

Shelton E. Murinda ◽

Paul D. Ebner ◽

Lien T. Nguyen ◽

Alan G. Mathew ◽

Stephen P. Oliver

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Dairy Farms ◽

Class 1 Integrons ◽

Pathogenic Escherichia Coli ◽

Class 1

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Identification and characterization of two novel ISCR1-associated genes dfrA42 and dfrA43 encoding trimethoprim resistant dihydrofolate reductases

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02010-20 ◽

2021 ◽

Author(s):

Ling Li ◽

Mengge Zhang ◽

Wenjia Wang ◽

Ruirui Xia ◽

Yanan Ma ◽

...

Keyword(s):

Escherichia Coli ◽

Complex Class ◽

Class 1 Integrons ◽

Class 1 ◽

Dihydrofolate Reductases ◽

High Level ◽

Identification And Characterization

Two novel ISCR1-associated dfr genes, dfrA42 and dfrA43, were identified from trimethoprim (TMP)-resistant Proteus strains and were shown to confer high level TMP resistance (MIC ≥ 1024 mg/L) when cloned into Escherichia coli. These genes were hosted by complex class 1 integrons suggesting their potentials for dissemination. Analysis of enzymatic parameters and TMP affinity were performed, suggesting that the mechanism of TMP resistance for these novel DHFRs is the reduction of binding with TMP.

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Characterization of Integrons and Antimicrobial Resistance in Escherichia coli Sequence Type 131 Isolates

Canadian Journal of Infectious Diseases and Medical Microbiology ◽

10.1155/2020/3826186 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Jiangqing Huang ◽

Fangjun Lan ◽

Yanfang Lu ◽

Bin Li

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Sequence Type ◽

Broth Culture ◽

Gene Cassettes ◽

E Coli ◽

Class 1

Background. Escherichia coli sequence type 131 (ST131) is an important multidrug-resistant extraintestinal pathogen, which can cause many kinds of infections. Integrons may play a crucial role in the dissemination of antibiotic resistance genes. The purpose of this study was to characterize the prevelance of integrons among E. coli ST131 strains in China. Methods. Eighty-three E. coli ST131 isolates were used in this study. The antibiotic susceptibility test was performed by the disk diffusion method. The presence and characterization of class 1, 2, and 3 integrons, as well as promotor of gene cassettes and other antimicrobial resistance genes, were detected by PCR and DNA sequencing. Transfer of integrons was carried out using a broth culture mating method. Clonal relatedness of E. coli ST131 isolates was analyzed by PFGE. Results. Overall, 26.5% (22/83) of the E. coli ST131 isolates carried class 1 integrons. Class 2 and 3 integrons were not found in this study. Two types of gene cassette arrays were demonstrated in this study and were as follows: dfrA17-aadA5 and aac(6′)-Ib-cr-cmlA5. Only one type of Pc promoter variant was detected among 22 integron-positive isolates (PcW). In vivo transfer of integron was successful for 9 of integron-positive E. coli ST131 isolates harboring resistance gene cassettes. Results of PFGE demonstrated that the integron-positive E. coli ST131 isolates were grouped into 12 different PFGE clusters. Conclusions. Our study showed a low prevalence of integrons was detected in E. coli ST131. Continued surveillance of this mobile genetic element should be performed to study the evolution of antibiotic resistance among E. coli ST131.

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