Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains

Background In previous studies, we have shown that atypical enteropathogenic Escherichia coli (aEPEC) strains are important diarrheal pathogens among Brazilian children. In the characterization of a collection of 126 aEPEC strains, we identified 29 strains expressing the localized-like adherence (LA...

Full description

Bibliographic Details
Main Authors: Scarlat S. Silva, Mariane V. Monfardini, Isabel C. A. Scaletsky
Format: Article
Language:English
Published: BMC 2020-05-01
Series:BMC Microbiology
Subjects:
Online Access:http://link.springer.com/article/10.1186/s12866-020-01809-4
_version_ 1819133684005994496
author Scarlat S. Silva
Mariane V. Monfardini
Isabel C. A. Scaletsky
author_facet Scarlat S. Silva
Mariane V. Monfardini
Isabel C. A. Scaletsky
author_sort Scarlat S. Silva
collection DOAJ
description Background In previous studies, we have shown that atypical enteropathogenic Escherichia coli (aEPEC) strains are important diarrheal pathogens among Brazilian children. In the characterization of a collection of 126 aEPEC strains, we identified 29 strains expressing the localized-like adherence (LAL) pattern on HEp-2 cells and harboring large plasmids in the range of 60 to 98 MDa. In this study, we examined 18 of these strains for their ability to transfer the LAL phenotype to a E. coli K-12 C600 strain. Results In conjugation experiments, using eight strains which were resistant to one or more antimicrobials and positive for F-pili genes (traA), we were able to cotransfer antimicrobial resistance markers along with adhesion genes. By transforming E. coli DH5α with plasmid DNA from strains A46 (pIS46), A66 (pIS66) and A102 (pIS102), we were able to demonstrate that genes encoding ampicillin, tetracycline and LAL were encoded on a 98-MDa conjugative plasmid. To identify a gene responsible for LAL, we constructed a transposon mutant library of A102 strain. Among 18 mutants that did not adhere to HeLa cells, four carried insertions within fimbrial genes (fimA and traJ) and agglutinin genes (tia and hek). Using these Tn5 mutants as donors, we were able to obtain kanamycin-resistant E. coli MA3456 transconjugants. Sequence analysis of the plasmid genes revealed a region exhibit to 80 and 73% amino acid similarities to the agglutinins Tia and Hek, respectively. Conclusion In this study, we have identified three large conjugative plasmids, pIS46, pIS66 and pIS102, coding for antimicrobial resistance and localized-like adherence (LAL) to HeLa cells. In addition, we identified a tia/hek homolog encoded on the pIS102 plasmid, which seems to be involved in adhesion of A102 strain.
first_indexed 2024-12-22T09:51:12Z
format Article
id doaj.art-75bdef9e205843f18459bfc28df2d82f
institution Directory Open Access Journal
issn 1471-2180
language English
last_indexed 2024-12-22T09:51:12Z
publishDate 2020-05-01
publisher BMC
record_format Article
series BMC Microbiology
spelling doaj.art-75bdef9e205843f18459bfc28df2d82f2022-12-21T18:30:21ZengBMCBMC Microbiology1471-21802020-05-012011810.1186/s12866-020-01809-4Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strainsScarlat S. Silva0Mariane V. Monfardini1Isabel C. A. Scaletsky2Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Escola Paulista de MedicinaDepartamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Escola Paulista de MedicinaDepartamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, Escola Paulista de MedicinaBackground In previous studies, we have shown that atypical enteropathogenic Escherichia coli (aEPEC) strains are important diarrheal pathogens among Brazilian children. In the characterization of a collection of 126 aEPEC strains, we identified 29 strains expressing the localized-like adherence (LAL) pattern on HEp-2 cells and harboring large plasmids in the range of 60 to 98 MDa. In this study, we examined 18 of these strains for their ability to transfer the LAL phenotype to a E. coli K-12 C600 strain. Results In conjugation experiments, using eight strains which were resistant to one or more antimicrobials and positive for F-pili genes (traA), we were able to cotransfer antimicrobial resistance markers along with adhesion genes. By transforming E. coli DH5α with plasmid DNA from strains A46 (pIS46), A66 (pIS66) and A102 (pIS102), we were able to demonstrate that genes encoding ampicillin, tetracycline and LAL were encoded on a 98-MDa conjugative plasmid. To identify a gene responsible for LAL, we constructed a transposon mutant library of A102 strain. Among 18 mutants that did not adhere to HeLa cells, four carried insertions within fimbrial genes (fimA and traJ) and agglutinin genes (tia and hek). Using these Tn5 mutants as donors, we were able to obtain kanamycin-resistant E. coli MA3456 transconjugants. Sequence analysis of the plasmid genes revealed a region exhibit to 80 and 73% amino acid similarities to the agglutinins Tia and Hek, respectively. Conclusion In this study, we have identified three large conjugative plasmids, pIS46, pIS66 and pIS102, coding for antimicrobial resistance and localized-like adherence (LAL) to HeLa cells. In addition, we identified a tia/hek homolog encoded on the pIS102 plasmid, which seems to be involved in adhesion of A102 strain.http://link.springer.com/article/10.1186/s12866-020-01809-4Atypical enteropathogenic Escherichia coliLocalized adherence-likeAntimicrobial resistancePlasmids
spellingShingle Scarlat S. Silva
Mariane V. Monfardini
Isabel C. A. Scaletsky
Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
BMC Microbiology
Atypical enteropathogenic Escherichia coli
Localized adherence-like
Antimicrobial resistance
Plasmids
title Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
title_full Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
title_fullStr Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
title_full_unstemmed Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
title_short Large plasmids encoding antibiotic resistance and localized-like adherence in atypical enteropathogenic Escherichia coli strains
title_sort large plasmids encoding antibiotic resistance and localized like adherence in atypical enteropathogenic escherichia coli strains
topic Atypical enteropathogenic Escherichia coli
Localized adherence-like
Antimicrobial resistance
Plasmids
url http://link.springer.com/article/10.1186/s12866-020-01809-4
work_keys_str_mv AT scarlatssilva largeplasmidsencodingantibioticresistanceandlocalizedlikeadherenceinatypicalenteropathogenicescherichiacolistrains
AT marianevmonfardini largeplasmidsencodingantibioticresistanceandlocalizedlikeadherenceinatypicalenteropathogenicescherichiacolistrains
AT isabelcascaletsky largeplasmidsencodingantibioticresistanceandlocalizedlikeadherenceinatypicalenteropathogenicescherichiacolistrains