Isothermal assay targeting class 1 integrase gene for environmental surveillance of antibiotic resistance markers

Introduction: Vibrio (V.) parahaemolyticus has endemically established in Chilean sea shores, causing outbreaks every year, with an important number of cases. In order to know the genetic relationship, genotype dominance and antibiotic resistance of isolates obtained from two outbreaks, this study characterized 110 strains isolated from environmental and clinical samples in years 2005 and 2007 in Chile. Methodology: Genotyping was performed by determination of PFGE profiles, and pandemic group and integrons were screened by PCR. Antimicrobial susceptibility was studied by the disk diffusion method. Results: High antibiotic susceptibility frequency was found, mainly among 2007 isolates, except to ampicillin, cephalothin, cefoxitin, cefpodoxime, amikacin, streptomycin and kanamycin. Strains belonging to the pandemic group in clinical isolates account for 88% in 2005, decreasing to 66% in 2007 and among environmental isolates were detected in 20% of the strains from 2005, rising to 36% in 2007. In 2005, nine different PFGE profiles were identified, with 78% of the strains corresponding to a single clone. In 2007, sixteen different PFGE profiles were detected, with 61% of the strains included into a sole clone. The same clone was prevalent in both years. None of class 1, 2, 3 and SXT integrases genes was detected; however, the superintegron integrase gene (intIA) was present in almost all strains. Conclusions: These results suggest the persistence and dominance of a unique PFGE clone of V. parahaemolyticus during 2005 and 2007, and the absence of genetic elements that capture antibiotic resistance genes described in other species of Vibrio.

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Prevalence of class 1 and 2 integrons among the multidrug resistant uropathogenic strains of Escherichia coli

Asian Biomedicine ◽

10.5372/1905-7415.0901.367 ◽

2017 ◽

Vol 9 (1) ◽

pp. 49-54 ◽

Cited By ~ 1

Author(s):

Haddadi Azam ◽

Somayeh Mikaili Ghezeljeh ◽

Shavandi Mahmoud

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Integrase Gene ◽

Class 1 ◽

Tract Infections

Abstract Background Multidrug resistance is a serious problem in the treatment of urinary tract infections. Horizontal gene transfer, directed by strong selective pressure of antibiotics, has resulted in the widespread distribution of multiple antibiotic resistance genes. The dissemination of resistance genes is enhanced when they are trapped in integrons. Objectives To determine the prevalence of integrons among multidrug resistant Escherichia coli strains collected from regional hospitals and private clinical laboratories in Alborz province. Methods The susceptibility of 111 clinical Escherichia coli isolates was tested using a Kirby–Bauer disk diffusion method for common antibiotics. Isolates were screened for the production of extended spectrum β-lactamases (ESBLs) using a double disk synergy test. The existence of integrons was confirmed by amplification of the integrase gene and their class determined via analysis of PCR products by PCR-RFLP. Results Isolates showed the highest resistance to amoxicillin. Nitrofurantoin, amikacin, and ceftizoxime were the most effective antibiotics in vitro. Eighty-eight isolates of 111 (79%) were resistant to more than three unrelated drugs. We found 30% of the multidrug resistant isolates harbor integrons. Class 1 and 2 integrons were detected in 25 and 1 isolates, respectively. ESBL screening of strains showed 45 isolates (40%) were positive; 22% of the ESBL-positive isolates carried class 1 integrons and the frequency of MDR in ESBLpositive isolates was 93%. Conclusion The existence of integrons in only 29.5% of multidrug resistant isolates showed that besides integrons, antibiotic resistance genes were probably carried on other transferable elements lacking integrons, such as transposons or plasmids.

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Biochar and Hyperthermophiles as Additives Accelerate the Removal of Antibiotic Resistance Genes and Mobile Genetic Elements during Composting

Materials ◽

10.3390/ma14185428 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5428

Author(s):

Yanli Fu ◽

Aisheng Zhang ◽

Tengfei Guo ◽

Ying Zhu ◽

Yanqiu Shao

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

High Throughput Sequencing ◽

Sewage Treatment ◽

Antibiotic Resistance Genes ◽

Mobile Genetic Elements ◽

Integrase Gene ◽

Genetic Elements ◽

Real Time Quantitative Pcr ◽

Class 1

Sewage treatment plants are known as repositories of antibiotic resistance genes (ARGs). Adding biochar and inoculating with exogenous microbial agents are common ways to improve the quality of compost. However, little is known about the effects of these exogenous additives on the fate of ARGs during composting and the related mechanisms. In this study, municipal sludge was taken as the research object to study the ARG-removal effects of four composting methods: ordinary compost (CT), compost with hyperthermophiles (HT), compost with hyperthermophiles and 2.0% biochar (HT2C) and compost with hyperthermophiles and 5.0% biochar (HT5C). Real-time quantitative PCR (qPCR) and 16S rRNA high-throughput sequencing were conducted to analyze the ARGs, MGEs and bacterial community. After composting, the abundance of ARGs in CT was reduced by 72.7%, while HT, HT2C and HT5C were reduced by 80.7%, 84.3% and 84.8%, respectively. Treatments with different proportions of biochar added (HT2C, HT5C) had no significant effect on the abundance of ARGs. Network analysis showed that Firmicutes and Nitrospirae were positively associated with most ARGs and may be potential hosts for them. In addition, redundancy analysis further showed that the class 1 integrase gene (intI1), pH and organic carbon had a greater effect on ARGs. Our findings suggested that the combination of hyperthermophiles and biochar during the composting process was an effective way to control ARGs and mobile genetic elements (MGEs), thus inhibiting the spread and diffusion of ARGs in the environment and improving the efficiency of treating human and animal diseases.

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Molecular Characterization of Class 3 Integrons from Delftia spp.

Journal of Bacteriology ◽

10.1128/jb.00348-07 ◽

2007 ◽

Vol 189 (17) ◽

pp. 6276-6283 ◽

Cited By ~ 50

Author(s):

Hai Xu ◽

Julian Davies ◽

Vivian Miao

Keyword(s):

Antibiotic Resistance ◽

Antibiotic Resistance Genes ◽

Gene Cassette ◽

Integrase Gene ◽

Delftia Acidovorans ◽

Sequence Identity ◽

Chromosomal Genes ◽

Class 1 ◽

Delftia Tsuruhatensis

ABSTRACT Two environmental strains, Delftia acidovorans C17 and Delftia tsuruhatensis A90, were found to carry class 3 integrons, which have seldom been reported and then only from pathogens in which they are associated with antibiotic resistance genes. The Delftia integrons comprised a highly conserved class 3 integrase gene, upstream and oppositely oriented from a set of three or four gene cassettes that encoded unidentified functions. The A90 integron had one more gene cassette than the C17 integron, but the two were otherwise the same; furthermore, they were located within regions of sequence identity in both strains and linked to chromosomal genes. A screen of other Delftia and related strains did not reveal the presence of additional class 3 integrons. The observations suggest that these integrons were horizontally transferred to Delftia as part of a larger region and reside as chromosomal elements that probably predate transposon dissemination, as has been proposed for certain class 1 integrons.

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IntI2 Integron Integrase in Tn7

Journal of Bacteriology ◽

10.1128/jb.184.6.1712-1721.2002 ◽

2002 ◽

Vol 184 (6) ◽

pp. 1712-1721 ◽

Cited By ~ 128

Author(s):

Karin Hansson ◽

Lars Sundström ◽

Alex Pelletier ◽

Paul H. Roy

Keyword(s):

Amino Acids ◽

Antibiotic Resistance ◽

Stop Codon ◽

Antibiotic Resistance Genes ◽

Peptide Sequence ◽

Integrase Gene ◽

Site Specific ◽

Class 1 Integrons ◽

Parental Allele ◽

Class 1

ABSTRACT Integrons can insert and excise antibiotic resistance genes on plasmids in bacteria by site-specific recombination. Class 1 integrons code for an integrase, IntI1 (337 amino acids in length), and are generally borne on elements derived from Tn5090, such as that found in the central part of Tn21. A second class of integron is found on transposon Tn7 and its relatives. We have completed the sequence of the Tn7 integrase gene, intI2, which contains an internal stop codon. This codon was found to be conserved among intI2 genes on three other Tn7-like transposons harboring different cassettes. The predicted peptide sequence (IntI2*) is 325 amino acids long and is 46% identical to IntI1. In order to detect recombination activity, the internal stop codon at position 179 in the parental allele was changed to a triplet coding for glutamic acid. The sequences flanking the cassette arrays in the class 1 and 2 integrons are not closely related, but a common pool of mobile cassettes is used by the different integron classes; two of the three antibiotic resistance cassettes on Tn7 and its close relatives are also found in various class 1 integrons. We also observed a fourth excisable cassette downstream of those described previously in Tn7. The fourth cassette encodes a 165-amino-acid protein of unknown function with 6.5 contiguous repeats of a sequence coding for 7 amino acids. IntI2*179E promoted site-specific excision of each of the cassettes in Tn7 at different frequencies. The integrases from Tn21 and Tn7 showed limited cross-specificity in that IntI1 could excise all cassettes from both Tn21 and Tn7. However, we did not observe a corresponding excision of the aadA1 cassette from Tn21 by IntI2*179E.

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Characterization of Integrons and Sulfonamide Resistance Genes among Bacteria from Drinking Water Distribution Systems in Southwestern Nigeria

Chemotherapy ◽

10.1159/000446150 ◽

2016 ◽

Vol 62 (1) ◽

pp. 34-42 ◽

Cited By ~ 6

Author(s):

Ayodele T. Adesoji ◽

Adeniyi A. Ogunjobi ◽

Isaac O. Olatoye

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Water Samples ◽

Distribution Systems ◽

Water Distribution ◽

Tap Water ◽

Bacterial Species ◽

Water Distribution Systems ◽

Integrase Gene ◽

Class 1

Background: The emergence of antibiotic resistance among pathogenic bacteria in clinical and environmental settings is a global problem. Many antibiotic resistance genes are located on mobile genetic elements such as plasmids and integrons, enabling their transfer among a variety of bacterial species. Water distribution systems may be reservoirs for the spread of antibiotic resistance. Materials and Methods: Bacteria isolated from raw, treated, and municipal tap water samples from selected water distribution systems in south-western Nigeria were investigated using the point inoculation method with seeded antibiotics, PCR amplification, and sequencing for the determination of bacterial resistance profiles and class 1/2 integrase genes and gene cassettes, respectively. Results:sul1,sul2, and sul3 were detected in 21.6, 27.8, and 0% of the isolates, respectively (n = 162). Class 1 and class 2 integrons were detected in 21.42 and 3.6% of the isolates, respectively (n = 168). Genes encoding resistance to aminoglycosides (aadA2, aadA1, and aadB), trimethoprim (dfrA15, dfr7, and dfrA1), and sulfonamide (sul1) were detected among bacteria with class 1 integrons, while genes that encodes resistance to strepthothricin (sat2) and trimethoprim (dfrA15) were detected among bacteria with class 2 integrons. Conclusions: Bacteria from these water samples are a potential reservoir of multidrug-resistant traits including sul genes and mobile resistance elements, i.e. the integrase gene.

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Faculty Opinions recommendation of Gram-positive bacteria are a major reservoir of Class 1 antibiotic resistance integrons in poultry litter.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1018990.214525 ◽

2004 ◽

Author(s):

Tamar Barkay

Keyword(s):

Antibiotic Resistance ◽

Poultry Litter ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Class 1

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Antimicrobial Resistance and Presence of Class 1 Integrons Among Different Serotypes of Salmonella spp. Recovered From Children with Diarrhea in Tehran, Iran

Infectious Disorders - Drug Targets ◽

10.2174/1871526519666190130171020 ◽

2020 ◽

Vol 20 (2) ◽

pp. 160-166

Author(s):

Seyedeh Hanieh Eshaghi Zadeh ◽

Hossein Fahimi ◽

Fatemeh Fardsanei ◽

Mohammad Mehdi Soltan Dallal

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Multidrug Resistant ◽

Salmonella Spp ◽

Class 1 Integron ◽

Class 1 Integrons ◽

Food Borne ◽

Class 1 ◽

Resistance Patterns ◽

C 30

Background: Salmonellosis is a major food-borne disease worldwide. The increasing prevalence of antimicrobial resistance among food-borne pathogens such as Salmonella spp. is concerning. Objective: The main objective of this study is to identify class 1 integron genes and to determine antibiotic resistance patterns among Salmonella isolates from children with diarrhea. Methods: A total of 30 Salmonella isolates were recovered from children with diarrhea. The isolates were characterized for antimicrobial susceptibility and screened for the presence of class 1 integron genes (i.e. intI1, sulI1, and qacEΔ1). Results: The most prevalent serotype was Enteritidis 36.7%, followed by Paratyphi C (30%), and Typhimurium (16.7%). The highest rates of antibiotic resistance were obtained for nalidixic acid (53.3%), followed by streptomycin (40%), and tetracycline (36.7%). Regarding class 1 integrons, 36.7%, 26.7%, and 33.3% of the isolates carried intI1, SulI, and qacEΔ1, respectively, most of which (81.8%) were multidrug-resistant (MDR). Statistical analysis revealed that the presence of class 1 integron was significantly associated with resistance to streptomycin and tetracycline (p = 0.042). However, there was no association between class 1 integron and other antibiotics used in this study (p > 0.05). Conclusion: The high frequency of integron class 1 gene in MDR Salmonella strains indicates that these mobile genetic elements are versatile among different Salmonella serotypes, and associated with reduced susceptibility to many antimicrobials.

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