Identification and characterization of the locus for diffuse adherence, which encodes a novel afimbrial adhesin found in atypical enteropathogenic Escherichia coli

Isabel C A Scaletsky, Jane Michalski, Alfredo Torres, Michelle V. Dulguer, James B. Kaper

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The O26 serogroup of enteropathogenic Escherichia coli (EPEC) is one of the serogroups most frequently implicated in infant diarrhea and is also common among enterohemorrhagic E. coli (EHEC) strains. The most common O26 strains belong to EPEC/EHEC serotype O26:H11 and are generally Shiga toxin (Stx) positive. Stx-negative E. coli strains that are negative for the EPEC EAF plasmid and bundle-forming pilus (Bfp) are classified as atypical EPEC. Here, we report a novel adhesin present in an stx-negative bfpA-negative atypical EPEC O26:H11 strain isolated from an infant with diarrhea. A cloned 15-kb genomic region from this strain, designated the locus for diffuse adherence (lda), confers diffuse adherence on HEp-2 cells when expressed in E. coli K-12. Sequence analysis of lda revealed a G+C content of 46.8% and 15 open reading frames sharing homology with the E. coli K88 fae and CS31A clp fimbrial operons. The lda region is part of a putative 26-kb genomic island inserted into the proP gene of the E. coli chromosome. Hybridization studies have demonstrated the prevalence of the minor structural subunit gene, ldaH, across E. coli serogroups O5, O26, O111, and O145. A second plasmid-encoded factor that contributed to the Hep-2 adherence of this strain was also identified but was not characterized. Null mutations that abolish adherence to HEp-2 cells can be restored by plasmid complementation. Antiserum raised against the major structural subunit, LdaG, recognizes a 25-kDa protein from crude heat-extracted protein preparations and inhibits the adherence of the E. coli DH5α lda+ clone to HEp-2 cells. Electron microscopy revealed a nonfimbrial structure surrounding the bacterial cell.

Original languageEnglish (US)
Pages (from-to)4753-4765
Number of pages13
JournalInfection and Immunity
Volume73
Issue number8
DOIs
StatePublished - Aug 2005

Fingerprint

Enteropathogenic Escherichia coli
Escherichia coli
Shiga Toxin
Enterohemorrhagic Escherichia coli
Plasmids
Diarrhea
Bacterial Structures
Genomic Islands
Base Composition
Operon
Open Reading Frames
Genes
Sequence Analysis
Immune Sera
Electron Microscopy
Proteins
Clone Cells
Hot Temperature
Chromosomes
Mutation

ASJC Scopus subject areas

  • Immunology

Cite this

Identification and characterization of the locus for diffuse adherence, which encodes a novel afimbrial adhesin found in atypical enteropathogenic Escherichia coli. / Scaletsky, Isabel C A; Michalski, Jane; Torres, Alfredo; Dulguer, Michelle V.; Kaper, James B.

In: Infection and Immunity, Vol. 73, No. 8, 08.2005, p. 4753-4765.

Research output: Contribution to journalArticle

@article{639c3fa6807c454180467e4e2d6bf649,
title = "Identification and characterization of the locus for diffuse adherence, which encodes a novel afimbrial adhesin found in atypical enteropathogenic Escherichia coli",
abstract = "The O26 serogroup of enteropathogenic Escherichia coli (EPEC) is one of the serogroups most frequently implicated in infant diarrhea and is also common among enterohemorrhagic E. coli (EHEC) strains. The most common O26 strains belong to EPEC/EHEC serotype O26:H11 and are generally Shiga toxin (Stx) positive. Stx-negative E. coli strains that are negative for the EPEC EAF plasmid and bundle-forming pilus (Bfp) are classified as atypical EPEC. Here, we report a novel adhesin present in an stx-negative bfpA-negative atypical EPEC O26:H11 strain isolated from an infant with diarrhea. A cloned 15-kb genomic region from this strain, designated the locus for diffuse adherence (lda), confers diffuse adherence on HEp-2 cells when expressed in E. coli K-12. Sequence analysis of lda revealed a G+C content of 46.8{\%} and 15 open reading frames sharing homology with the E. coli K88 fae and CS31A clp fimbrial operons. The lda region is part of a putative 26-kb genomic island inserted into the proP gene of the E. coli chromosome. Hybridization studies have demonstrated the prevalence of the minor structural subunit gene, ldaH, across E. coli serogroups O5, O26, O111, and O145. A second plasmid-encoded factor that contributed to the Hep-2 adherence of this strain was also identified but was not characterized. Null mutations that abolish adherence to HEp-2 cells can be restored by plasmid complementation. Antiserum raised against the major structural subunit, LdaG, recognizes a 25-kDa protein from crude heat-extracted protein preparations and inhibits the adherence of the E. coli DH5α lda+ clone to HEp-2 cells. Electron microscopy revealed a nonfimbrial structure surrounding the bacterial cell.",
author = "Scaletsky, {Isabel C A} and Jane Michalski and Alfredo Torres and Dulguer, {Michelle V.} and Kaper, {James B.}",
year = "2005",
month = "8",
doi = "10.1128/IAI.73.8.4753-4765.2005",
language = "English (US)",
volume = "73",
pages = "4753--4765",
journal = "Infection and Immunity",
issn = "0019-9567",
publisher = "American Society for Microbiology",
number = "8",

}

TY - JOUR

T1 - Identification and characterization of the locus for diffuse adherence, which encodes a novel afimbrial adhesin found in atypical enteropathogenic Escherichia coli

AU - Scaletsky, Isabel C A

AU - Michalski, Jane

AU - Torres, Alfredo

AU - Dulguer, Michelle V.

AU - Kaper, James B.

PY - 2005/8

Y1 - 2005/8

N2 - The O26 serogroup of enteropathogenic Escherichia coli (EPEC) is one of the serogroups most frequently implicated in infant diarrhea and is also common among enterohemorrhagic E. coli (EHEC) strains. The most common O26 strains belong to EPEC/EHEC serotype O26:H11 and are generally Shiga toxin (Stx) positive. Stx-negative E. coli strains that are negative for the EPEC EAF plasmid and bundle-forming pilus (Bfp) are classified as atypical EPEC. Here, we report a novel adhesin present in an stx-negative bfpA-negative atypical EPEC O26:H11 strain isolated from an infant with diarrhea. A cloned 15-kb genomic region from this strain, designated the locus for diffuse adherence (lda), confers diffuse adherence on HEp-2 cells when expressed in E. coli K-12. Sequence analysis of lda revealed a G+C content of 46.8% and 15 open reading frames sharing homology with the E. coli K88 fae and CS31A clp fimbrial operons. The lda region is part of a putative 26-kb genomic island inserted into the proP gene of the E. coli chromosome. Hybridization studies have demonstrated the prevalence of the minor structural subunit gene, ldaH, across E. coli serogroups O5, O26, O111, and O145. A second plasmid-encoded factor that contributed to the Hep-2 adherence of this strain was also identified but was not characterized. Null mutations that abolish adherence to HEp-2 cells can be restored by plasmid complementation. Antiserum raised against the major structural subunit, LdaG, recognizes a 25-kDa protein from crude heat-extracted protein preparations and inhibits the adherence of the E. coli DH5α lda+ clone to HEp-2 cells. Electron microscopy revealed a nonfimbrial structure surrounding the bacterial cell.

AB - The O26 serogroup of enteropathogenic Escherichia coli (EPEC) is one of the serogroups most frequently implicated in infant diarrhea and is also common among enterohemorrhagic E. coli (EHEC) strains. The most common O26 strains belong to EPEC/EHEC serotype O26:H11 and are generally Shiga toxin (Stx) positive. Stx-negative E. coli strains that are negative for the EPEC EAF plasmid and bundle-forming pilus (Bfp) are classified as atypical EPEC. Here, we report a novel adhesin present in an stx-negative bfpA-negative atypical EPEC O26:H11 strain isolated from an infant with diarrhea. A cloned 15-kb genomic region from this strain, designated the locus for diffuse adherence (lda), confers diffuse adherence on HEp-2 cells when expressed in E. coli K-12. Sequence analysis of lda revealed a G+C content of 46.8% and 15 open reading frames sharing homology with the E. coli K88 fae and CS31A clp fimbrial operons. The lda region is part of a putative 26-kb genomic island inserted into the proP gene of the E. coli chromosome. Hybridization studies have demonstrated the prevalence of the minor structural subunit gene, ldaH, across E. coli serogroups O5, O26, O111, and O145. A second plasmid-encoded factor that contributed to the Hep-2 adherence of this strain was also identified but was not characterized. Null mutations that abolish adherence to HEp-2 cells can be restored by plasmid complementation. Antiserum raised against the major structural subunit, LdaG, recognizes a 25-kDa protein from crude heat-extracted protein preparations and inhibits the adherence of the E. coli DH5α lda+ clone to HEp-2 cells. Electron microscopy revealed a nonfimbrial structure surrounding the bacterial cell.

UR - http://www.scopus.com/inward/record.url?scp=23344434624&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=23344434624&partnerID=8YFLogxK

U2 - 10.1128/IAI.73.8.4753-4765.2005

DO - 10.1128/IAI.73.8.4753-4765.2005

M3 - Article

VL - 73

SP - 4753

EP - 4765

JO - Infection and Immunity

JF - Infection and Immunity

SN - 0019-9567

IS - 8

ER -