Skip to main content
  • ASM
    • Antimicrobial Agents and Chemotherapy
    • Applied and Environmental Microbiology
    • Clinical Microbiology Reviews
    • Clinical and Vaccine Immunology
    • EcoSal Plus
    • Eukaryotic Cell
    • Infection and Immunity
    • Journal of Bacteriology
    • Journal of Clinical Microbiology
    • Journal of Microbiology & Biology Education
    • Journal of Virology
    • mBio
    • Microbiology and Molecular Biology Reviews
    • Microbiology Resource Announcements
    • Microbiology Spectrum
    • Molecular and Cellular Biology
    • mSphere
    • mSystems
  • Log in
  • My alerts
  • My Cart

Main menu

  • Home
  • Articles
    • Current Issue
    • Accepted Manuscripts
    • Archive
    • Minireviews
  • For Authors
    • Submit a Manuscript
    • Scope
    • Editorial Policy
    • Submission, Review, & Publication Processes
    • Organization and Format
    • Errata, Author Corrections, Retractions
    • Illustrations and Tables
    • Nomenclature
    • Abbreviations and Conventions
    • Publication Fees
    • Ethics Resources and Policies
  • About the Journal
    • About IAI
    • Editor in Chief
    • Editorial Board
    • For Reviewers
    • For the Media
    • For Librarians
    • For Advertisers
    • Alerts
    • RSS
    • FAQ
  • Subscribe
    • Members
    • Institutions
  • ASM
    • Antimicrobial Agents and Chemotherapy
    • Applied and Environmental Microbiology
    • Clinical Microbiology Reviews
    • Clinical and Vaccine Immunology
    • EcoSal Plus
    • Eukaryotic Cell
    • Infection and Immunity
    • Journal of Bacteriology
    • Journal of Clinical Microbiology
    • Journal of Microbiology & Biology Education
    • Journal of Virology
    • mBio
    • Microbiology and Molecular Biology Reviews
    • Microbiology Resource Announcements
    • Microbiology Spectrum
    • Molecular and Cellular Biology
    • mSphere
    • mSystems

User menu

  • Log in
  • My alerts
  • My Cart

Search

  • Advanced search
Infection and Immunity
publisher-logosite-logo

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Accepted Manuscripts
    • Archive
    • Minireviews
  • For Authors
    • Submit a Manuscript
    • Scope
    • Editorial Policy
    • Submission, Review, & Publication Processes
    • Organization and Format
    • Errata, Author Corrections, Retractions
    • Illustrations and Tables
    • Nomenclature
    • Abbreviations and Conventions
    • Publication Fees
    • Ethics Resources and Policies
  • About the Journal
    • About IAI
    • Editor in Chief
    • Editorial Board
    • For Reviewers
    • For the Media
    • For Librarians
    • For Advertisers
    • Alerts
    • RSS
    • FAQ
  • Subscribe
    • Members
    • Institutions
Molecular Pathogenesis

Expression of Hemin Receptor Molecule ChuA Is Influenced by RfaH in Uropathogenic Escherichia coliStrain 536

Gábor Nagy, Ulrich Dobrindt, Maren Kupfer, Levente Emödy, Helge Karch, Jörg Hacker
Gábor Nagy
Institut für Molekulare Infektionsbiologie, Universität Würzburg, 97070 Würzburg, and
Institute of Medical Microbiology and Immunology, University of Pécs, 7624 Pécs, Hungary
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Ulrich Dobrindt
Institut für Molekulare Infektionsbiologie, Universität Würzburg, 97070 Würzburg, and
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Maren Kupfer
Institut für Molekulare Infektionsbiologie, Universität Würzburg, 97070 Würzburg, and
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Levente Emödy
Institute of Medical Microbiology and Immunology, University of Pécs, 7624 Pécs, Hungary
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Helge Karch
Institut für Hygiene und Mikrobiologie, Universität Würzburg, 97080 Würzburg, Germany, and
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Jörg Hacker
Institut für Molekulare Infektionsbiologie, Universität Würzburg, 97070 Würzburg, and
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
DOI: 10.1128/IAI.69.3.1924-1928.2001
  • Article
  • Figures & Data
  • Info & Metrics
  • PDF
Loading

ABSTRACT

The outer membrane protein ChuA responsible for hemin utilization has been recently identified in several pathogenic Escherichia coli strains. We report that the regulatory protein RfaH influences ChuA expression in the uropathogenic E. colistrain 536. In an rfaH mutant, the chuAtranscript as well as the ChuA protein levels were significantly decreased in comparison with those in the wild-type strain. Within thechuA gene, a consensus motif known as the JUMPStart (just upstream of many polysaccharide associated gene starts) sequence was found, which is shared by RfaH-affected operons. Furthermore, the presence of two different subclasses of thechuA determinant and their distribution in E. coli pathogroups are described.

The availability of iron, an essential nutrient for bacterial growth, is severely limited in mammalian hosts. In order to compete with the host for iron, pathogenic bacteria have developed different mechanisms to acquire this essential growth factor (10). Low-molecular-weight chelators (siderophores) are secreted by several pathogens. These molecules liberate Fe3+ from host carriers and transport it into bacterial cells. Alternatively, many pathogenic bacteria can directly utilize iron-containing host compounds through specific receptors. Several gram-negative pathogens, e.g., Haemophilus influenzae type b (6), yersiniae (34, 37), Vibrio cholerae (26), neisseriae (17, 35), and Shigella dysenteriae(21), express outer membrane proteins involved in the utilization of heme and its protein complexes as iron sources. InEscherichia coli O157:H7 the gene chuA, which codes for a 69-kDa outer membrane protein responsible for heme uptake, was recently identified (38). The chuAnucleotide sequence shows high homology to that of the formerly described shuA gene of S. dysenteriae type 1 (40). The gene is part of a larger locus, termed the heme transport locus, which appears to be widely distributed among pathogenic E. coli strains (41). This locus contains eight open reading frames and is located at 78.7 min of theE. coli K-12 chromosome.

The ability to use heme and/or hemoglobin might be especially advantageous to pathogenic bacteria. These pathogens often secrete cytotoxins, which gain access to the intracellular heme reservoir besides initiating tissue invasion. Cytotoxin production coupled with the capability to utilize heme and/or hemoglobin could serve as an effective iron acquisition strategy during the progression of infection.

RfaH regulates the transcription of long operons probably at the level of transcription antitermination, hence suppressing operon polarity (2, 18). These operons share a conserved motif, which was identified for the first time in polysaccharide-associated operons and was therefore termed the JUMPStart (for just upstream of many polysaccharide-associated gene starts) sequence (12). The most-conserved part of this 39-bp motif is an 8-bp sequence termed theops element (for operon polarity suppressor), which is always associated with a direct repeat that shows less similarity to the standard element (2). Deletion of the opselement and/or other parts of the JUMPStart sequence results in transcriptional polarity of the affected operons (19, 24). A similar transcriptional pattern is observed in rfaHmutants, suggesting that the regulation of these operons by RfaH is dependent on the presence of the JUMPStart motif. In this study we investigated the effect of RfaH on the expression of the E. coli hemin receptor protein ChuA.

Bacterial strains and culture conditions.The uropathogenicE. coli strain 536 was isolated from a patient with acute pyelonephritis (3). In the mutant strain 536rfaH::cat, the rfaH gene was inactivated by insertion of a chloramphenicol acetyltransferase (cat) cassette. The insertion was performed by allelic exchange as previously described (23).trans-complementation of rfaH was achieved by supplying the mutant strain with the plasmid pSMK1, which carriedrfaH together with its promoter region cloned into the vector pGEM-T Easy (Promega). The strains used in Southern hybridization experiments are listed in Table1. The enterohemorrhagic E. coli (EHEC) strain 95004730 and the enteroaggregativeE. coli (EAggEC) strain DPA065 were provided by Robert Pringle (Victorian Infectious Diseases Reference Laboratory, North Melbourne, Australia) and Anna Giammanco (Dipartimento di Igiene e Microbiologia, University of Palermo, Palermo, Italy), respectively. The origins of all otherE. coli wild-type strains are referenced in Table 1. Bacteria were grown routinely in Luria-Bertani broth or Luria-Bertani broth solidified with 1.5% agar (Difco, Detroit, Mich.). In iron-restricted studies, a 0.4 mM concentration of the iron chelator 2,2′-dipyridyl (Sigma, Deisenhofen, Germany) was added to the media. When appropriate, the medium was supplemented with the following antibiotics at the indicated concentrations: ampicillin, 100 μg/ml; chloramphenicol, 30 μg/ml.

View this table:
  • View inline
  • View popup
Table 1.

Occurrence of chuA and the two distinctchuA upstream regions among pathogenic E. coli strains

Expression of ChuA is decreased in the rfaH mutant of strain 536.The ChuA protein levels expressed in E. coli 536 and its derivatives were determined by Western blotting (Fig. 1A). Whole-cell extracts obtained from bacteria grown in normal and iron-restricted media were separated on a 10% polyacrylamide gel and were blotted onto a nitrocellulose membrane. The blocked membranes were treated with an anti-HemR antiserum (kindly provided by J. Heesemann) and were developed as described elsewhere (28). HemR is the hemin receptor protein of Yersinia enterocolitica. The HemR antiserum was proven to be cross-reactive with ChuA of E. coli 536 (data not shown). The quantity of ChuA protein was strongly reduced in the rfaH-negative strain compared to the wild type.trans-complementation of the mutant strain withrfaH (on pSMK1) restored higher levels of ChuA. No ChuA protein was detectable in the absence of 2,2′-dipyridyl, indicating that expression of ChuA is dependent on the availability of free iron.

Fig. 1.
  • Open in new tab
  • Download powerpoint
Fig. 1.

Influence of RfaH on chuA expression ofE. coli strain 536. (A) Detection of ChuA levels by Western blot analysis of whole-cell extracts of E. colistrain 536 and its derivatives using a HemR-specific antiserum. The strains were grown in the presence (+) or absence (−) of 0.4 mM 2,2′-dipyridyl. (B) Analysis of chuA transcript levels of E. coli strain 536 and its derivatives. An enhanced chemiluminescence-labeled chuA-specific probe was hybridized to total RNA isolated from strain 536 (lane 1), 536rfaH::cat (lane 2), 536rfaH::cat (pSMK1) (lane 3). The 23S and 16S rRNA were stained with 0.3% methylene blue after transfer of separated total RNA to a nylon membrane (internal control).

To investigate whether the altered expression of ChuA protein was a consequence of decreased chuA transcription in therfaH mutant, we performed Northern blot analysis (Fig. 1B). Total RNA was isolated from bacteria harvested from iron-restricted medium using the RNeasy Mini Kit (Qiagen, Hilden, Germany). Northern blot analysis was performed as described previously (1). Ten micrograms of isolated RNA per lane was separated on a 1.2% agarose-formaldehyde gel and was transferred overnight to a nylon membrane (Biodyne B; Pall Ltd., Portsmouth, England) by capillary blotting. The DNA probe specific for the 3′ end of chuA was generated by PCR using the primers 5′-GTCGCTTCTATACCAACTATTGGGTG-3′ and 5′-CCGTTACGACCATCCTGTG-3′ and was labeled with the ECL direct labeling system (Amersham-Pharmacia, Freiburg, Germany). Hybridization was carried out overnight at 42°C as described by Amersham-Pharmacia. Before luminography, the membrane was washed twice for 15 min in 0.5× SSC (1× SSC is 0.15 M NaCl plus 0.015 M sodium citrate)–0.4% sodium dodecyl sulfate (SDS) (50°C) and then twice for 5 min in 2× SSC (20°C). The chuA-specific DNA probe hybridized to a 2.2 to 2.3-kb mRNA, which corresponds to thechuA transcript (Fig. 1B). The absence of an intactrfaH gene resulted in reduced levels of chuAmRNA; however, the length of the transcript was not altered. Overexpression of RfaH (536rfaH::cat carrying pSMK1) manifested in an increased chuA transcription compared to the level found in the wild-type strain. RfaH has been known as a regulator which influences the transcription of long operons encoding cell surface and extracellular components that are important for bacterial fertility and virulence. These include the hly, rfa, rfb, tra, cps, and kps operons that direct the synthesis of α-hemolysin, lipopolysaccharide core, O antigen, F factor, and group I and group II capsule, respectively (2). The hemin receptor ChuA is also anchored in the outer membrane of pathogenic E. coli strains and is considered to be a potential virulence factor. As the encoding gene (chuA) is transcribed as a monocistronic mRNA, the way RfaH is involved in transcriptional regulation of chuAtranscription seems to be inconsistent with the present view that RfaH acts as a transcriptional antiterminator without affecting transcription initiation (18).

Coregulation of different determinants involved in pathogenicity is energetically advantageous for pathogenic bacteria. This is especially true for components of a complex system which are functionally related. α-Hemolysin expression and hemin uptake are both regulated by iron (16, 21), suggesting that the utilization of heme compounds liberated from eukaryotic cells is an important iron acquisition strategy during infection. Coupled regulation by RfaH gives further evidence that the function of theE. coli hemin uptake system (chu) is dependent on secreted hemolysin.

Sequence analysis of the chuA gene of E. coli strain 536.Sequencing of the chuA gene was performed from a cosmid clone of E. coli 536 using an ABI Prism 310 automatic sequencer. It was previously shown that RfaH-regulated operons carry a conserved region known as the JUMPStart sequence (2). Within the chuA gene ofE. coli strain 536, a similar motif was identified. A comparison of this motif to JUMPStart sequences of other E. coli operons known to be regulated by RfaH is shown in Fig.2. The 39-bp region found in thechuA gene is located 1,158 bp downstream of the start codon. It contains an ops-like motif with an additional conserved C base located downstream of the ops element. In the 5′ region of the JUMPStart sequence, a relatively well-conserved direct repeat could be identified with relevant spacing similar to those of other JUMPStart sequences.

Fig. 2.
  • Open in new tab
  • Download powerpoint
Fig. 2.

Comparison of JUMPStart sequences from differentE. coli operons. Boldface letters denote theops element; underlined bases represent the imperfect repeats within the JUMPStart sequences. Accession numbers or references for the following sequences are as follows: cps,AF104912 ; kps, X53819 ; rfb, U09876 ;tra, U01159 ; rfa, M86935 ; p152hly, M14107 and X07565 ; 2001 hly, reference24; J96 hly, M10133 ; 536 hlyI andhlyII, G. Nagy and G. Blum-Oehler, unpublished data; 536chu, AF280396 ; EDL933 chu, U67920 .

The 1,983-bp coding region of chuA shows high homology to the corresponding sequences derived from E. coliO157:H7 (38) and S. dysenteriae(22). The potential promoter region is located about 300 bp upstream of the start codon, and is overlapped by a putative Fur box. The presence of this motif neighboring the promoter explains the observed effect of iron availability on ChuA protein levels. In contrast to the high homology between the coding regions of differentchuA and shuA determinants, the E. coli 536-specific chuA upstream region showed less similarity to the corresponding regions of E. coli O157:H7 and S. dysenteriae. A 74-bp region located between the putative promoter and the start codon of the E. coli 536-specific determinant is replaced by a totally different 73-bp motif in S. dysenteriae and E. coli O157:H7 (Fig.3). In the uropathogenic strain, this region is flanked by 6-bp direct repeats that might have served as a site for recombination. In E. coli O157:H7, this region is bordered by similar, nevertheless imperfect, repeats.

Fig. 3.
  • Open in new tab
  • Download powerpoint
Fig. 3.

Genetic map of the uropathogenic E. colistrain 536-specific chuA gene (A) and that of EHEC strain EDL933 (B). The chuA coding regions are indicated by boxes; the 5′ flanking regions are indicated by single lines. The arrows labeled with P denote the promoters. The sequences of the upstream element specific for strain 536 or strain EDL933 are given. Bases in boldface type represent the direct repeats flanking dissimilar regions. The numbers and thick lines denote the probes used for Southern hybridization (see text). The sequences of oligonucleotides used as probes are underlined.

To investigate the distribution of the two different identified 5′-flanking sequences of chuA, several E. coli strains representing different pathogroups were tested by Southern hybridization. Chromosomal DNA was isolated as described before (9). The DNA was digested with BglI prior to separation on a 0.8% agarose gel and subsequent transfer to a nylon membrane (Biodyne B; Pall Ltd.) The presence of chuAin the genomes was proven by hybridization of a 600-bp probe derived from the well-conserved 3′ part of chuA (probe-1). Generation, labeling, and detection of the chuA-specific probe as well as the hybridization procedure were performed as described above for Northern blot analysis. Oligonucleotides derived from the dissimilar upstream regions were used to analyze the distribution of the different 5′ flanking regions. Probe-2 (derived from strain 536 [Fig. 3]) (5′-TGA ATT ATC AGA AAT ATT CGG CAA TTT TAC GGG ATA TAT ACG CTA ATA GCT TCC CGT GGT GAT ATC TAA TCA-3′) and probe-3 (derived from the strain EDL933 [Fig. 3]) (5′-CGA GTT ATC AGG CAA TTT CAT GGG ATA TAA ACG C-3′) were purchased from ARK Scientific GmbH (Darmstadt, Germany). The probes were labeled with digoxigenin using the DIG Oligonucleotide 3′-End Labeling kit (Roche, Mannheim, Germany). Prehybridization and hybridization were carried out in high-SDS hybridization buffer at 30°C for 4 h and overnight, respectively. The filters were washed twice for 10 min at room temperature in 2× SSC–0.1% SDS. Hybridized oligonucleotides were detected using the DIG Luminescent Detection kit (Roche) following the standard protocol provided by the manufacturer. The results of the hybridization experiments are summarized in Table 1.

The probe specific for the 3′ end of the chuA gene (probe-1) hybridized with numerous intestinal and all extraintestinal pathogenic E. coli strains. However, thechuA-specific probe hybridized to two distinct bands: to a larger DNA fragment (∼12 kb) in case of the extraintestinal and some of the enteropathogenic E. coli (EPEC) strains, whereas in EHEC O157, enteroinvasive E. coli(EIEC) and some other EPEC strains the chuA probe hybridized to a smaller fragment (∼11 kb). In correspondence with former investigations, none of the tested non-O157-EHEC, EAggEC, and enterotoxigenic E. coli representatives carriedchuA (41). The oligonucleotide specific for thechuA upstream region of strain 536 (probe-2) hybridized to all strains that carried chuA on the 12-kb fragment, while that which originated from the O157:H7 strain EDL933 (probe-3) hybridized to the 11-kb fragment, suggesting that two distinct variants of the chuA determinant, which show differences in their flanking sequences, exist. The existence of these two variants and their patterned distribution among different pathogroups provides further evidence for the clonality of E. colipathogens. Whether the differences in the chuA upstream regions have any influence on the regulation of chuAexpression still needs to be clarified.

Nucleotide sequence accession number.The nucleotide sequence of the E. coli strain 536-specific chuA gene has been deposited in the GenBank database (accession numberAF280396 ).

ACKNOWLEDGMENTS

We thank Jürgen Heesemann for supplying the HemR antiserum.

Our work was supported by the Deutsche Forschungsgemeinschaft (Ha 1434/8-2, SFB 479) and the Fonds der Chemischen Industrie. G.N. was supported by a grant from the Bayerische Forschungsstiftung.

Notes

Editor: J. T. Barbieri

FOOTNOTES

    • Received 8 September 2000.
    • Returned for modification 20 October 2000.
    • Accepted 4 December 2000.
  • Copyright © 2001 American Society for Microbiology

REFERENCES

  1. 1.↵
    1. Ausubel F. M.,
    2. Brent R.,
    3. Kingston R. E.,
    4. Moore D. D.,
    5. Seidman J. G.,
    6. Smith J. A.,
    7. Struhl K.
    Current protocols in molecular biology 4 1987 John Wiley & Sons New York, N.Y
  2. 2.↵
    1. Bailey M. J. A.,
    2. Hughes C.,
    3. Koronakis V.
    RfaH and the ops element, components of a novel system controlling bacterial transcription elongation.Mol. Microbiol.261997845851
    OpenUrlCrossRefPubMedWeb of Science
  3. 3.↵
    1. Berger H.,
    2. Hacker J.,
    3. Juarez A.,
    4. Hughes C.,
    5. Goebel W.
    Cloning of the chromosomal determinants encoding hemolysin production and mannose-resistant hemagglutination in Escherichia coli.J. Bacteriol.152198212411247
    OpenUrlAbstract/FREE Full Text
  4. 4.
    1. Bokete T. N.,
    2. Whittam T. S.,
    3. Wilson R. A.,
    4. Clausen C. R.,
    5. O'Callahan C. M.,
    6. Moseley S. L.,
    7. Fritsche T. R.,
    8. Tarr P. I.
    Genetic and phenotypic analysis of Escherichia coli with enteropathogenic characteristics isolated from Seattle children.J. Infect. Dis.175199713821389
    OpenUrlCrossRefPubMedWeb of Science
  5. 5.
    1. Boyer H. V.,
    2. Roulland-Dussoix D.
    A complementation analysis of the restriction and modification of DNA in Escherichia coli.J. Mol. Biol.411969459472
    OpenUrlCrossRefPubMedWeb of Science
  6. 6.↵
    1. Cope L. D.,
    2. Yogev R.,
    3. Muller-Eberhard U.,
    4. Hansen E. J.
    A gene cluster involved in the utilization of both free heme and heme:hemopexin by Haemophilus influenzae type b.J. Bacteriol.177199526442653
    OpenUrlAbstract/FREE Full Text
  7. 7.
    1. Datz M.,
    2. Janetzki-Mittmann C.,
    3. Franke S.,
    4. Gunzer F.,
    5. Schmidt H.,
    6. Karch H.
    Analysis of the enterohemorrhagic Escherichia coli O157 DNA region containing lambdoid phage gene p and Shiga-like toxin structural genes.Appl. Environ. Microbiol.621996791797
    OpenUrlAbstract/FREE Full Text
  8. 8.
    1. Donnenberg M. S.,
    2. Tzipori S.,
    3. McKee M. L.,
    4. O'Brien A. D.,
    5. Alroy J.,
    6. Kaper J. B.
    The role of the eae gene of enterohemorrhagic Escherichia coli in intimate attachment in vitro and in a porcine model.J. Clin. Investig.3199314181424
    OpenUrl
  9. 9.↵
    1. Grimberg J.,
    2. Maguire S.,
    3. Belluscio L.
    A simple method for the preparation of plasmid and chromosomal DNA.Nucleic Acids Res.2119898893
    OpenUrl
  10. 10.↵
    1. Guerinot M. L.
    Microbial iron transport.Annu. Rev. Microbiol.481994743772
    OpenUrlCrossRefPubMedWeb of Science
  11. 11.
    1. Hii J. H.,
    2. Gyles C.,
    3. Morooka T.,
    4. Karmali M. A.,
    5. Clarke R.,
    6. De Grandis S.,
    7. Brunton J. L.
    Development of verotoxin 2- and verotoxin 2 variant (VT2v)-specific oligonucleotide probes on the basis of the nucleotide sequence of the B cistron of VT2v from Escherichia coliE32511and B2F1.J. Clin. Microbiol.29199127042709
    OpenUrlAbstract/FREE Full Text
  12. 12.↵
    1. Hobbs M.,
    2. Reeves P. R.
    The JUMPstart sequence: a 39 bp element common to several polysaccharide gene clusters.Mol. Microbiol.121994855856
    OpenUrlCrossRefPubMedWeb of Science
  13. 13.
    1. Hull R. A.,
    2. Gill R. E.,
    3. Hsu P.,
    4. Minshew B. H.,
    5. Falkow S.
    Construction and expression of recombinant plasmids encoding type 1 or d-mannose-resistant pili from a urinary tract infection Escherichia coli isolate.Infect. Immun.331981933936
    OpenUrlAbstract/FREE Full Text
  14. 14.
    1. Karch H.,
    2. Böhm H.,
    3. Schmidt H.,
    4. Gunzer F.,
    5. Aleksic S.,
    6. Heesemann J.
    Clonal structure and pathogenicity of Shiga-like toxin-producing, sorbitol-fermenting Escherichia coli O157:H−.J. Clin. Microbiol.31199312001205
    OpenUrlAbstract/FREE Full Text
  15. 15.
    1. Korhonen T. K.,
    2. Valtonen M. V.,
    3. Parkkinen J.,
    4. Vaisänen-Rhen V.,
    5. Finne J.,
    6. Ørskov F.,
    7. Ørskov I.,
    8. Svenson S. B.,
    9. Mäkelä P. H.
    Serotypes, hemolysin production, and receptor recognition of Escherichia coli strains associated with neonatal sepsis and meningitis.Infect. Immun.481985486491
    OpenUrlAbstract/FREE Full Text
  16. 16.↵
    1. Lebek G.,
    2. Grünig H. M.
    Relation between the hemolytic property and iron metabolism in Escherichia coli.Infect. Immun.501985682686
    OpenUrlAbstract/FREE Full Text
  17. 17.↵
    1. Lee B. C.
    Isolation of haemin-binding proteins of Neisseria gonorrhoeae.J. Med. Microbiol.361992121127
    OpenUrlCrossRefPubMedWeb of Science
  18. 18.↵
    1. Leeds J. A.,
    2. Welch R. A.
    RfaH enhances elongation of Escherichia coli hlyCABD mRNA.J. Bacteriol.178199618501857
    OpenUrlAbstract/FREE Full Text
  19. 19.↵
    1. Leeds J. A.,
    2. Welch R. A.
    Enhancing transcription through the Escherichia coli hemolysin operon, hlyCABD: RfaH and upstream JUMPstart DNA sequences function together via a postinitiation mechanism.J. Bacteriol.179199735193527
    OpenUrlAbstract/FREE Full Text
  20. 20.
    1. Levine M. M.,
    2. Bergquist E. J.,
    3. Nalin D. R.,
    4. Waterman D. H.,
    5. Hornick R. B.,
    6. Young C. R.,
    7. Sotman S.
    Escherichia coli strains that cause diarrhoea but do not produce heat-labile or heat-stable enterotoxins and are non-invasive.Lanceti197811191122
    OpenUrlCrossRefPubMedWeb of Science
  21. 21.↵
    1. Mills M.,
    2. Payne S. M.
    Genetics and regulation of heme iron transport in Shigella dysenteriae and detection of an analogous system in Escherichia coli O157:H7.J. Bacteriol.177199530043009
    OpenUrlAbstract/FREE Full Text
  22. 22.↵
    1. Mills M.,
    2. Payne S. M.
    Identification of shuA, the gene encoding the heme receptor of Shigella dysenteriae, and analysis of invasion and intracellular multiplication of a shuA mutant.Infect. Immun.65199753585363
    OpenUrlAbstract/FREE Full Text
  23. 23.↵
    1. Mobley H. L.,
    2. Jarvis K. G.,
    3. Elwood J. P.,
    4. Whittle D. I.,
    5. Lockatell C. V.,
    6. Russell R. G.,
    7. Johnson D. E.,
    8. Donnenberg M. S.,
    9. Warren J. W.
    Isogenic P-fimbrial deletion mutants of pyelonephritogenic Escherichia coli: the role of alpha Gal(1-4) beta Gal binding in virulence of a wild-type strain.Mol. Microbiol.101993143155
    OpenUrlCrossRefPubMedWeb of Science
  24. 24.↵
    1. Nieto J. M.,
    2. Bailey M. J. A.,
    3. Hughes C.,
    4. Koronakis V.
    Suppression of transcription polarity in the Escherichia coli haemolysin operon by a short upstream element shared by polysaccharide and DNA transfer determinants.Mol. Microbiol.191996705713
    OpenUrlCrossRefPubMed
  25. 25.
    1. O'Brien A. D.,
    2. Lively T. A.,
    3. Chang T. W.,
    4. Gorbach S. L.
    Purification of Shigella dysenteriae 1 (Shiga)-like toxin from Escherichia coli O157:H7 strain associated with haemorrhagic colitis.Lancetii1983573
    OpenUrl
  26. 26.↵
    1. O'Malley S. M.,
    2. Mouton S. L.,
    3. Occhino D. A.,
    4. Deanda M. T.,
    5. Rashidi J. R.,
    6. Fuson K. L.,
    7. Rashidi C. E.,
    8. Mora M. Y.,
    9. Payne S. M.,
    10. Henderson D. P.
    Comparison of the heme iron utilization systems of pathogenic vibrios.J. Bacteriol.181199935943598
    OpenUrlAbstract/FREE Full Text
  27. 27.
    1. Ott M.,
    2. Hacker J.,
    3. Schmoll T.,
    4. Jarchau T.,
    5. Korhonen T. K.,
    6. Goebel W.
    Analysis of the genetic determinants coding for the S-fimbrial adhesin (sfa) in different Escherichia coli strains causing meningitis or urinary tract infections.Infect. Immun.541986646653
    OpenUrlAbstract/FREE Full Text
  28. 28.↵
    1. Ritter A.,
    2. Gally D. L.,
    3. Olsen P. B.,
    4. Dobrindt U.,
    5. Friedrich A.,
    6. Klemm P.,
    7. Hacker J.
    The Pai-associated leuX specific tRNA5Leu affects type 1 fimbriation in pathogenic Escherichia coli by control of FimB recombinase expression.Mol. Microbiol.251997871882
    OpenUrlCrossRefPubMedWeb of Science
  29. 29.
    1. Rüssmann H.,
    2. Kothe E.,
    3. Schmidt H.,
    4. Franke S.,
    5. Harmsen D.,
    6. Caprioli A.,
    7. Karch H.
    Genotyping of Shiga-like toxin genes in non-O157 Escherichia coli strains associated with haemolytic uraemic syndrome.J. Med. Microbiol.421995404410
    OpenUrlCrossRefPubMedWeb of Science
  30. 30.
    1. Rüssmann H.,
    2. Schmidt H.,
    3. Caprioli A.,
    4. Karch H.
    Highly conserved B-subunit genes of Shiga-like toxin II variants found in Escherichia coli O157 strains.FEMS Microbiol. Lett.1181994335340
    OpenUrlPubMed
  31. 31.
    1. Rüssmann H.,
    2. Schmidt H.,
    3. Heesemann J.,
    4. Caprioli A.,
    5. Karch H.
    Variants of Shiga-like toxin II constitute a major toxin component in Escherichia coli O157 strains from patients with haemolytic uraemic syndrome.J. Med. Microbiol.401994338343
    OpenUrlCrossRefPubMedWeb of Science
  32. 32.
    1. Schmidt H.,
    2. Geitz C.,
    3. Tarr P. I.,
    4. Frosch M.,
    5. Karch H.
    Non-O157:H7 pathogenic Shiga toxin-producing Escherichia coli: phenotypic and genetic profiling of virulence traits and evidence for clonality.J. Infect. Dis.1791999115123
    OpenUrlCrossRefPubMedWeb of Science
  33. 33.
    1. Silver R. P.,
    2. Finn C. W.,
    3. Vann W. F.,
    4. Aaronson W.,
    5. Schneerson R.,
    6. Kretschmer P. J.,
    7. Garon C. F.
    Molecular cloning of the K1 capsular polysaccharide genes of E. coli.Nature2891981696698
    OpenUrlCrossRefPubMed
  34. 34.↵
    1. Stojiljkovic I.,
    2. Hantke K.
    Hemin uptake system of Yersinia enterocolitica: similarities with other TonB-dependent systems in gram-negative bacteria.EMBO J.11199243594367
    OpenUrlPubMedWeb of Science
  35. 35.↵
    1. Stojiljkovic I.,
    2. Hwa V.,
    3. de Saint Martin L.,
    4. O'Gaora P.,
    5. Nassif X.,
    6. Heffron F.,
    7. So M.
    The Neisseria meningitidis haemoglobin receptor: its role in iron utilization and virulence.Mol. Microbiol.151995531541
    OpenUrlCrossRefPubMed
  36. 36.
    1. Tarr P. I.,
    2. Neill M. A.,
    3. Clausen C. R.,
    4. Newland J. W.,
    5. Neill R. J.,
    6. Moseley S. L.
    Genotypic variation in pathogenic Escherichia coli O157:H7 isolated from patients in Washington, 1984-1987.J. Infect. Dis.1591989344347
    OpenUrlCrossRefPubMedWeb of Science
  37. 37.↵
    1. Thompson J. M.,
    2. Jones H. A.,
    3. Perry R. D.
    Molecular characterization of the hemin uptake locus (hmu) from Yersinia pestis and analysis of hmu mutants for hemin and hemoprotein utilization.Infect. Immun.67199938793892
    OpenUrlAbstract/FREE Full Text
  38. 38.↵
    1. Torres A. G.,
    2. Payne S. M.
    Haem iron-transport system in enterohaemorrhagic Escherichia coli O157:H7.Mol. Microbiol.231997825833
    OpenUrlCrossRefPubMedWeb of Science
  39. 39.
    1. van Die I.,
    2. van Geffen B.,
    3. Hoekstra W.,
    4. Bergmans H.
    Type 1C fimbriae of a uropathogenic Escherichia coli strain: cloning and characterization of the genes involved in the expression of the 1C antigen and nucleotide sequence of the subunit gene.Gene341985187196
    OpenUrlCrossRefPubMedWeb of Science
  40. 40.↵
    1. Vial P. A.,
    2. Robins-Browne R.,
    3. Lior H.,
    4. Prado V.,
    5. Kaper J. B.,
    6. Nataro J. P.,
    7. Maneval D.,
    8. Elsayed A.,
    9. Levine M. M.
    Characterization of enteroadherent-aggregative Escherichia coli, a putative agent of diarrheal disease.J. Infect. Dis.15819887079
    OpenUrlCrossRefPubMedWeb of Science
  41. 41.↵
    1. Wyckoff E. E.,
    2. Duncan D.,
    3. Torres A. G.,
    4. Mills M.,
    5. Maase K.,
    6. Payne S. M.
    Structure of the Shigella dysenteriae haem transport locus and its phylogenetic distribution in enteric bacteria.Mol. Microbiol.28199811391152
    OpenUrlCrossRefPubMedWeb of Science
  42. 42.
    1. Zhang W.-L.,
    2. Bielaszewska M.,
    3. Liesegang A.,
    4. Tschäpe H.,
    5. Schmidt H.,
    6. Bitzan M.,
    7. Karch H.
    Molecular characteristics and epidemiological significance of Shiga toxin-producing Escherichia coli O26 strains.J. Clin. Microbiol.38200021342140
    OpenUrlAbstract/FREE Full Text
  43. 43.
    1. Zingler G.,
    2. Blum G.,
    3. Falkenhagen U.,
    4. O/rskov I.,
    5. O/rskov F.,
    6. Hacker J.,
    7. Ott M.
    Clonal differentiation of uropathogenic Escherichia coli isolates of serotype O6:K5 by fimbrial antigen typing and DNA long-range mapping techniques.Med. Microbiol. Immunol.18219931324
    OpenUrlPubMed
PreviousNext
Back to top
Download PDF
Citation Tools
Expression of Hemin Receptor Molecule ChuA Is Influenced by RfaH in Uropathogenic Escherichia coliStrain 536
Gábor Nagy, Ulrich Dobrindt, Maren Kupfer, Levente Emödy, Helge Karch, Jörg Hacker
Infection and Immunity Mar 2001, 69 (3) 1924-1928; DOI: 10.1128/IAI.69.3.1924-1928.2001

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Print

Alerts
Sign In to Email Alerts with your Email Address
Email

Thank you for sharing this Infection and Immunity article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
Expression of Hemin Receptor Molecule ChuA Is Influenced by RfaH in Uropathogenic Escherichia coliStrain 536
(Your Name) has forwarded a page to you from Infection and Immunity
(Your Name) thought you would be interested in this article in Infection and Immunity.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Share
Expression of Hemin Receptor Molecule ChuA Is Influenced by RfaH in Uropathogenic Escherichia coliStrain 536
Gábor Nagy, Ulrich Dobrindt, Maren Kupfer, Levente Emödy, Helge Karch, Jörg Hacker
Infection and Immunity Mar 2001, 69 (3) 1924-1928; DOI: 10.1128/IAI.69.3.1924-1928.2001
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
  • Top
  • Article
    • ABSTRACT
    • ACKNOWLEDGMENTS
    • Notes
    • FOOTNOTES
    • REFERENCES
  • Figures & Data
  • Info & Metrics
  • PDF

KEYWORDS

Bacterial Outer Membrane Proteins
Escherichia coli
Escherichia coli Proteins
hemin
Peptide Elongation Factors
pyelonephritis
Receptors, Cell Surface
Trans-Activators

Related Articles

Cited By...

About

  • About IAI
  • Editor in Chief
  • Editorial Board
  • Policies
  • For Reviewers
  • For the Media
  • For Librarians
  • For Advertisers
  • Alerts
  • RSS
  • FAQ
  • Permissions
  • Journal Announcements

Authors

  • ASM Author Center
  • Submit a Manuscript
  • Article Types
  • Ethics
  • Contact Us

Follow #IAIjournal

@ASMicrobiology

       

ASM Journals

ASM journals are the most prominent publications in the field, delivering up-to-date and authoritative coverage of both basic and clinical microbiology.

About ASM | Contact Us | Press Room

 

ASM is a member of

Scientific Society Publisher Alliance

 

American Society for Microbiology
1752 N St. NW
Washington, DC 20036
Phone: (202) 737-3600

Copyright © 2021 American Society for Microbiology | Privacy Policy | Website feedback

Print ISSN: 0019-9567; Online ISSN: 1098-5522