Skip to main content

The contribution of small cryptic plasmids to the antibiotic resistance of enteropathogenic Escherichia coli E2348/69

Buy Article:

$50.00 plus tax (Refund Policy)


Two uncharacterized small cryptic plasmids (SCPs) were isolated from enteropathogenic Escherichia coli strain E2348/69. Genomic DNA sequence analysis of both SCPs indicated that the smaller plasmid, p5217, encoded several mobilization genes, whereas the larger plasmid, p6148, encoded several putative antibiotic resistance determinants. Complementation analysis showed that p6148 encodes functional streptomycin resistance genes but, owing to the presence of several frameshift mutations, a nonfunctional sulfonamide resistance determinant. A plasmid similar to p6148 has previously been shown to confer a slight growth advantage on E. coli. However, we were unable to observe any significant growth advantage in different E. coli strains transformed with p6148. The p6148 DNA sequence is homologous in sequence and arrangement to DNA from other plasmid families, including large conjugative plasmids and SXT integrative and conjugative elements. This study suggests that gene clusters of the sul2-strAB antibiotic resistance genes are widespread and highly transferable, owing to their presence in a wide variety of mobile genetic elements.

Deux petits plasmides cryptiques (SCP) encore non caractérisés ont été isolés de la souche entéropathogène d’Escherichia coli E2348/69. La séquence de l’ADN génomique des 2 plasmides SCP a indiqué que le plus petit plasmide, p5217, codait plusieurs gènes de mobilisation, alors que le plus grand plasmide, p6148, codait plusieurs déterminants présumés de la résistance aux antibiotiques. Des analyses de complémentation ont montré que p6148 code des gènes fonctionnels de résistance à la streptomycine, mais, à cause de la présence de plusieurs mutations de changement de phase, un déterminant de résistance au sulfonamide non fonctionnel. Un plasmide similaire à p6148 avait déjà été trouvé responsable du léger avantage de croissance de E. coli. Cependant, nous avons été incapables d’observer un avantage de croissance significatif chez les souches d’E. coli transformées avec p6148. L’ADN de p6148 est homologue à l’ADN d’autres familles de plasmides quant à la séquence et à l’arrangement, notamment les plasmides de conjugaison de grande taille et les éléments d’intégration et de conjugaison SXT. Cette étude suggère que les grappes des gènes de résistance aux antibiotiques sul2-strAB sont dispersées et sont hautement transférables à cause de la présence d’une grande variété d’éléments génétiques mobiles.

Document Type: Research Article

Publication date: November 1, 2009

More about this publication?
  • Published since 1954, this monthly journal contains new research in the field of microbiology including applied microbiology and biotechnology; microbial structure and function; fungi and other eucaryotic protists; infection and immunity; microbial ecology; physiology, metabolism and enzymology; and virology, genetics, and molecular biology. It also publishes review articles and notes on an occasional basis, contributed by recognized scientists worldwide.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • Sample Issue
  • Reprints & Permissions
  • ingentaconnect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more