Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1999 Jun;67(6):2692-9.
doi: 10.1128/IAI.67.6.2692-2699.1999.

Phylogenetic analysis of enteroaggregative and diffusely adherent Escherichia coli

J R Czeczulin  1 , T S Whittam, I R Henderson, F Navarro-Garcia, J P Nataro
Affiliations

Phylogenetic analysis of enteroaggregative and diffusely adherent Escherichia coli

J R Czeczulin et al. Infect Immun. 1999 Jun.

Abstract

The phylogenetics of the various pathotypes of diarrheagenic Escherichia coli are not completely understood. In this study, we identified several plasmid and chromosomal genes in the pathogenic enteroaggregative E. coli (EAEC) prototype strain 042 and determined the prevalence of these loci among EAEC and diffusely adherent E. coli strains. The distribution of these genes is analyzed within an evolutionary framework provided by the characterization of allelic variation in housekeeping genes via multilocus enzyme electrophoresis. Our data reveal that EAEC strains are heterogeneous with respect to chromosomal and plasmid-borne genes but that the majority harbor a member of a conserved family of virulence plasmids. Comparison of plasmid and chromosomal relatedness of strains suggests clonality of chromosomal markers and a limited transfer model of plasmid distribution.

PubMed Disclaimer

Figures

FIG. 1
FIG. 1
MluI restriction map of the 100-kb plasmid pAA2 from strain 042. The positions of plasmid-borne probes used in this work are indicated by open symbols; the positions of other genes mentioned in the text are indicated by solid symbols. Inner tick marks are 20 kb apart. Uppercase letters represent specific MluI fragments.
FIG. 2
FIG. 2
Phylogram of EAEC and DAEC strains. EAEC and DAEC strains were subjected to MLEE for 20 enzymes as previously described (39, 45). Results were analyzed by the neighbor-joining method. Bold italic letters refer to positive hybridization reactions with the probes listed in Table 2: a, CVD432; b, shf; c, AAF/I; d, pet; e, AAF/II; f, aggR; g, aspU; s, she homolog; i, irp2. DA, DAEC; NA, non-adherent strain; AA, EAEC (as defined by HEp-2 adherence phenotype). Dotted lines are added to assist in visual alignments. DEC clones represent diarrheagenic E. coli clusters previously described by Whittam et al. (45).
FIG. 3
FIG. 3
Southern blot hybridization of AA plasmids by using AAF/I or AAF/II-expressing cosmid clones as probes. Total plasmid DNA was extracted from the strains indicated below; the DNA was digested with EcoRV and separated by agarose gel electrophoresis. DNA was then blotted and hybridized using cosmid pJPN31 (which expresses AAF/I) (a) or cosmid D6 (which expresses AAF/II) (b). (a) Lane 1, JM221; lane 2, H145-1; lane 3, H194-2. (b) Lane 1, 042; lane 2, Peru49; lane 3, DS244R3; lane 4, 199-1.
See this image and copyright information in PMC

References

    1. Ausubel F M, Brent R, Kingston R E, Moore D D, Smith J A, Seidman J G, Struhl K, editors. Current protocols in molecular biology. New York, N.Y: John Wiley & Sons; 1989.
    1. Baudry B, Savarino S J, Vial P, Kaper J B, Levine M M. A sensitive and specific DNA probe to identify enteroaggregative Escherichia coli, a recently discovered diarrheal pathogen. J Infect Dis. 1990;161:1249–1251. - PubMed
    1. Bhan M K, Khoshoo V, Sommerfelt H, Raj P, Sazawal S, Srivastava R. Enteroaggregative Escherichia coli and Salmonella associated with nondysenteric persistent diarrhea. Pediatr Infect Dis J. 1989;8:499–502. - PubMed
    1. Bhan M K, Raj P, Levine M M, Kaper J B, Bhandari N, Srivastava R, Kumar R, Sazawal S. Enteroaggregative Escherichia coli associated with persistent diarrhea in a cohort of rural children in India. J Infect Dis. 1989;159:1061–1064. - PubMed
    1. Boerlin P, Chen S, Colbourne J K, Johnson R, De Grandis S, Gyles C. Evolution of enterohemorrhagic Escherichia coli hemolysin plasmids and the locus for enterocyte effacement in shiga toxin-producing E. coli. Infect Immun. 1998;66:2553–2561. - PMC - PubMed

Publication types

Associated data

LinkOut - more resources