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Bacterial Infections

Differential Effects of Epinephrine, Norepinephrine, and Indole on Escherichia coli O157:H7 Chemotaxis, Colonization, and Gene Expression

Tarun Bansal, Derek Englert, Jintae Lee, Manjunath Hegde, Thomas K. Wood, Arul Jayaraman
Tarun Bansal
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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Derek Englert
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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Jintae Lee
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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Manjunath Hegde
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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Thomas K. Wood
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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Arul Jayaraman
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122
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  • For correspondence: arulj@tamu.edu
DOI: 10.1128/IAI.00630-07
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  • FIG. 1.
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    FIG. 1.

    Agarose plug chemotaxis. Attraction or repulsion of E. coli O157:H7 to different chemical agents was determined using a modified agarose plug assay. Fluorescence images from bacteria exposed to 500 μM EPI (A), 500 μM NE (B), 2% Casamino Acids (C), 5,000 μM indole (D), 1 × 10−4 M glycerol (E), and 1× M9 salts solution (F) are shown. Green cells are E. coli O157:H7 expressing GFP, and red cells are kanamycin-killed E. coli TG1 expressing RFP. Fluorescence images were obtained on a Zeiss Axiovert 200 microscope after 30 min using a 10× objective. Data shown are representative images from three independent experiments. Arrows indicate chemoattractant ring (A), clearance zone (C), and chemorepellant band (D).

  • FIG. 2.
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    FIG. 2.

    EPI, NE, and indole affect E. coli O157:H7 motility and biofilm formation. The relative change in EHEC motility and biofilm upon exposure to EPI (50 μM), NE (50 μM), and indole (500 μM) was determined. Motility data are shown as means ± 1 standard deviation from 18 motility agar plates from three independent experiments. Biofilm data are means ± 1 standard deviation from 36 wells and three independent experiments. The asterisk indicates statistical significance determined using a Student t test (P < 0.01).

  • FIG. 3.
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    FIG. 3.

    Gene expression in E. coli O157:H7 biofilms upon exposure to EPI, NE, or indole. The effects of EPI (50 μM), NE (50 μM), and indole (500 μM) on gene expression in EHEC biofilms on glass wool were determined. The number of differentially expressed genes for each molecule, as well as the number of genes common to other molecules, is indicated in the Venn diagram. Genes common to all three molecules are not included in any of the other categories to facilitate interpretation. Annotated genes common to EPI, NE, and indole treatments (i.e., divergently expressed between EPI/NE and indole) are shown at right along with arrows indicating an increase or decrease in expression. E, epinephrine; IND, indole.

  • FIG. 4.
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    FIG. 4.

    EPI, NE, and indole affect E. coli O157:H7 attachment to HeLa cells. The relative change in EHEC attachment to HeLa cells after 3 h of exposure to EPI (50 μM), NE (50 μM), or indole (500 μM) was determined. Cell counts (means ± 1 standard deviation) are from duplicate LB agar plates and were generated from five HeLa cell culture wells. Control values are based on EHEC cell counts obtained without the addition of any molecule. Statistical significance was determined using a Student t test. *, P < 0.01; **, P < 0.005.

  • FIG. 5.
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    FIG. 5.

    Hypothetical model for E. coli O157:H7 colonization in the GI tract. Gradients of EPI and NE influence the chemotactic migration of E. coli O157:H7 to epithelial cell surfaces. Cells that do not encounter high concentrations of EPI and NE will continue to move parallel to, and not toward, the epithelial cell surface. (A) In the absence of indole-secreting commensal E. coli, colonization of the nonpathogenic biofilm occurs throughout the epithelial cell surface. (B) In the presence of commensal E. coli, the pathogen is exposed to gradients of indole which repel it from the host cells. In this scenario, colonization occurs only in regions where nonpathogenic, non-E. coli bacteria are present. The direction of migration is indicated by arrows.

Tables

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  • TABLE 1.

    Primers used for quantitative RT-PCR

    GeneASAP identifierForward primerReverse primer
    lsrA ABH-00259655′-AACATCCTGTTTGGGCTGGCAA-3′5′-AAACAAGCGTTCGGTTTCCGCA-3′
    lsrB ABH-00259625′-AGCATCCTGGCTGGGAAATTGT-3′5′-AAATTCTTTCACCGTGCCGCGT-3′
    lsrC ABH-00259645′-ACAGCGTTTGGACGCAGTTT-3′5′-ACGCAGGCTGCAATTGCTTT-3′
    rpoA ABH-00283245′-CGCGGTCGTGGTTATGTG-3′5′-GCGCTCATCTTCTTCCGAAT-3′
  • TABLE 2.

    Summary of changes in E. coli O157:H7 biofilm gene expression

    Gene type or function and nameRelative change in expression (n-fold) after exposure to:aDescription
    EPINEIND
    AI-2 group
        c19931.41.41.6Putative integral membrane transport protein
        lsrA −9.8 −5.3 1.0Fused AI-2 transporter subunits of ABC superfamily; ATP-binding components
        lsrB −7.0 −5.3 −1.4Putative LACI-type transcriptional regulator
        lsrC −4.3 −2.3 1.2AI-2 transporter
        lsrD −3.2 −1.41.5AI-2 transporter
        lsrG −3.2 −3.0 −1.1AI-2 modifying protein LsrG
        lsrK −2.8 −2.3 1.2AI-2 kinase
        lsrR −3.7 −3.7 1.1 lsr operon transcriptional repressor
    Phosphate related
        phnD −2.1 1.2 2.1 Phosphonates-binding periplasmic protein precursor
        phnG−1.11.5 2.3 PhnG protein
        phnP−1.21.3 2.1 PhnP protein
        phoB 2.1 3.0 −2.6 Phosphate regulon transcriptional regulatory protein phoB
        phoH −4.9 −4.6 −1.9PhoH protein
        phoR 2.6 3.5 −1.6Phosphate regulon sensor protein phoR
        phoU1.9 2.1 −3.7 Phosphate transport system protein phoU
        pstA 2.5 2.6 −3.2 Phosphate transport system permease protein pstA
        pstB1.31.5 −3.7 Phosphate transport ATP-binding protein pstB
        pstC 2.6 3.0 −2.3 Phosphate transport system permease protein pstC
        pstS1.11.1 −4.6 Phosphate-binding periplasmic protein precursor
        purE 3.0 3.7 1.4Phosphoribosylaminoimidazole carboxylase catalytic subunit
        purK1.2 2.6 1.6Phosphoribosylaminoimidazole carboxylase ATPase subunit
        purT−1.4 2.5 2.1 Phosphoribosylglycinamide formyltransferase 2
    Hydrognease
        hyaA −3.0 −3.2 1.1Hydrogenase-1 large chain
        hyaB −4.0 −3.5 1.2Hydrogenase-1 operon protein hyaE
        hyaC −3.7 −3.0 1.1Hydrogenase-1 operon protein hyaF
        hyaD −3.2 −2.8 1.2Hydrogenase-1 small chain precursor
        hyaE −3.5 −2.5 1.3Hydrogenase-1 large chain
        hyaF −3.0 −2.6 1.1Hydrogenase-1 operon protein hyaE
    PTS
        mtlA −13.9 −11.3 1.0PTS system; mannitol-specific IIABC component
        manX −4.6 −3.5 1.1PTS system; mannose-specific IIAB component
        manY −2.8 −2.3 1.1PTS system; mannose-specific IIC component
        manZ −2.8 −2.1 1.2PTS system; mannose-specific IID component
        fruB−1.7 −2.1 1.2PTS system; fructose-specific IIA/FPr component
    Glycerol related
        glgC −2.5 −3.0 −1.3Glucose-1-phosphate adenylyltransferase
        glpA −4.9 −1.71.7Anaerobic glycerol-3-phosphate dehydrogenase subunit A
        glpD −9.2 −18.4 1.3sn-Glycerol-3-phosphate dehydrogenase (aerobic)
        glpF −5.7 −5.7 1.3Glycerol uptake facilitator protein
        glpK −7.5 −6.1 1.1Glycerol kinase
        glpQ −2.1 −2.5 −1.1Glycerophosphoryl diester phosphodiesterase; periplasmic precursor
        glpR−1.6 −2.1 −1.1Glycerol-3-phosphate regulon repressor
        ugpB −7.0 −6.1 −1.4Glycerol-3-phosphate-binding periplasmic protein precursor
    Histidine biosynthesis
        hisA −2.1 −2.8 −1.61-(5-Phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino] imidazole-4-carboxamide isomerase
        hisB −2.3 −2.6 −2.1 Bifunctional: histidinol-phosphatase (N terminus) and imidazoleglycerol-phosphate dehydratase (C terminus)
        hisC −4.0 −4.6 −2.8 Histidinol-phosphate aminotransferase
        hisD −4.3 −4.3 −2.6 Histidine biosynthesis
        hisF −3.0 −3.0 −2.0 Imidazole glycerol phosphate synthase subunit hisF
        hisG1.1−1.3 −2.8 ATP phosphoribosyltransferase
        hisH−1.6 −2.1 −2.0 Imidazole glycerol phosphate synthase subunit hisH
        hisI −2.1 −2.0 −1.9Histidine biosynthesis
        hisL 3.0 1.1 −3.7 His operon leader peptide
        hisLEDL1.7−1.2 −3.5 Histidine biosynthesis; hisL gene from strain EDL933
        hisP −2.5 −1.4−1.1Nucleotide binding
    Two-component signal transduction
        dos1.3 2.1 1.4Putative phosphodiesterase, oxygen-sensing protein
        evgS −3.2 −1.5−1.2Two-component signal transduction system (phosphorelay)
        fimZ1.1 2.1 3.0 Fimbiral protein Z; putative transcriptional regulator of fimbrial expression (LuxR/UhpA family)
        glnL 3.2 2.5 −1.9Two-component signal transduction system (phosphorelay)
        narL −2.6 −2.0 −1.4Nitrate/nitrite response regulator protein narL
        prpR −3.5 −3.7 1.1Regulator for prp operon
        rstA 2.5 1.9−1.3Transcriptional Regulatory protein rstA
        yedV1.4 2.6 2.0 Putative two-component sensor protein
        ygeV −2.1 −1.4−1.5Two-component signal transduction system (phosphorelay)
    Sulfate
        cysD −3.0 −3.0 −1.6Sulfate adenylyltransferase (ATP) activity
        cysI −3.5 −3.0 −1.2Sulfite reductase [NADPH] hemoprotein beta-component
        cysJ −4.3 −2.8 1.0Sulfite reductase [NADPH] flavoprotein alpha-component
        sseA −2.1 −1.91.43-Mercaptopyruvate sulfurtransferase
    Motility/chemotaxis
        acs −8.0 −4.3 1.1Acetyl-coenzyme A synthetase
        c2129 3.0 2.5 1.5Cell division activator cedA
        c40041.32.11.1Hypothetical protein
        csgA −4.3 −2.8 1.5Cell adhesion
        csgB −5.7 −4.6 −1.1Minor curlin subunit precursor
        csgF −3.7 −2.5 −1.4Curli production assembly/transport component csgF precursor
        fimZ1.12.1 3.0 Fimbiral protein Z; putative transcriptional regulator of fimbrial expression (LuxR/UhpA family)
        fliD 2.0 2.1 1.4Cell motility
        fliR−1.11.9 2.3 Flagellar biosynthetic protein fliR
        gidB1.4 2.1 1.5Methyltransferase gidB
        motB −2.3 −1.21.3Chemotaxis motB protein
        mreC1.5 2.1 1.2Rod shape-determining protein mreC
        sfmA−1.21.5 2.1 Putative fimbrial-like protein
        sfmF1.01.5 2.3 Putative fimbrial-like protein
        sfmH −2.0 1.0 2.5 Fimbrial assembly protein
        yhhP1.7 2.5 1.5SirA protein
        Z00201.5 2.5 2.1 Cell adhesion
        Z4971−1.9 3.7 1.9Cell adhesion
    Cytochrome
        appB −3.0 −2.3 1.2Cytochrome bd II oxidase subunit II
        appC −2.5 −2.1 1.1Cytochrome bd II oxidase subunit I
        cyoC −2.1 −3.0 1.0Cytochrome o ubiquinol oxidase subunit III
        nrfA −3.2 −1.51.5Cytochrome c-552 precursor
        nrfB −2.8 1.01.5Cytochrome c-type protein nrfB precursor
    Cold shock protein
        cspA1.51.5 −3.2 Cold shock protein cspA
        cspE 2.3 2.5 −1.1Cold shock-like protein cspE
        cspG 8.0 6.1 −4.0 Cold shock-like protein cspG
        cspH 22.6 21.1 −2.5 Cold shock-like protein cspH
        deaD 2.1 2.6 −1.2Cold shock DEAD-box protein A
    Antisense RNA
        dsrA 3.5 4.9 1.3Antisense RNA; silencer of rcsA gene, interacts with rpoS translation
        rdlD 4.0 4.0 −2.5 Antisense RNA; trans-acting regulator of ldrD translation
        sokB 9.2 7.0 −1.1Antisense RNA blocking mokB and hokB translation
        sokC 2.0 2.6 −1.6Antisense RNA blocking mokC (orf69) and hokC (gef) translation
    Glutamine/glutamate
        c0018 24.3 24.3 5.7 Putative glutamate dehydrogenase
        glnA1.61.3 −2.3 Glutamine synthetase
        glnH−1.21.0 −2.1 Glutamine-binding periplasmic protein precursor
        glnP 2.5 3.0 −1.9Glutamine transport system permease protein glnP
        gltJ 3.7 4.3 −1.6Glutamate/aspartate transport system permease protein gltJ
        gltK 2.6 2.6 −1.6Glutamate/aspartate transport system permease protein gltK
        gltL1.41.7−1.9Glutamate/aspartate transport ATP-binding protein gltL
        ybeJ−1.3−1.1 −2.5 Glutamate/aspartate periplasmic binding protein precursor
    Iron related
        c3773 2.0 2.1 1.6Putative iron compound permease protein of ABC transporter family
        cydA 2.0 2.8 −1.1Cytochrome d ubiquinol oxidase subunit I
        cydB1.9 2.8 −1.2Cytochrome d ubiquinol oxidase subunit II
        feoA 2.5 2.6 −1.3Ferrous iron transport protein A
        feoB 2.0 3.2 1.0Ferrous iron transport protein B
        fhuB1.3 2.5 1.1Ferrichrome transport system permease protein fhuB
        fhuC1.6 2.5 1.0Ferrichrome transport ATP-binding protein fhuC
        fhuD 2.5 4.6 1.1Ferrichrome-binding periplasmic protein precursor
        yodB 2.5 2.6 −1.3Cytochrome b561 homolog 1
    NADH dehydrogenase
        nuoA−1.3 −2.5 1.1NADH dehydrogenase I chain A
        nuoB −2.0 −3.5 1.0NADH dehydrogenase I chain B
        nuoC−1.7 −4.0 −1.1NADH dehydrogenase I chain C/D
        nuoE −2.0 −4.3 −1.1NADH dehydrogenase I chain E
        nuoI−1.1 −2.5 1.1NADH dehydrogenase I chain I
        nuoJ−1.3 −2.5 1.3NADH dehydrogenase I chain J
        nuoK−1.3 −2.3 1.4NADH dehydrogenase I chain K
        nuoL−1.2 −2.3 1.4NADH dehydrogenase I chain L
    Tricarboxylic acid cycle
        sdhD −13.0 −21.1 1.1Succinate dehydrogenase hydrophobic membrane anchor protein
        sdhC −12.1 −18.4 1.1Succinate dehydrogenase cytochrome b-556 subunit
        sdhA −11.3 −16.0 1.3Succinate dehydrogenase, catalytic and NAD/flavoprotein subunit
        sdhB −10.6 −12.1 1.0Succinate dehydrogenase iron-sulfur protein
        sucA −7.5 −11.3 1.12-Oxoglutarate dehydrogenase E1 component
        sucB −7.0 −9.2 −1.1Dihydrolipoamide succinyltransferase component of 2-oxoglutarate dehydrogenase complex
        sucD −6.5 −8.6 1.0Succinyl-coenzyme A synthetase alpha chain
        sucC −6.5 −8.6 1.0Succinyl-coenzyme A synthetase beta chain
        acnB −2.0 −4.3 1.0Aconitate hydratase activity
        icdA−1.9 −2.6 1.1Isocitrate dehydrogenase [NADP]
        yojH−1.2 −2.3 −1.5Malate:quinone oxidoreductase
        mdh −2.0 −2.1 −1.1Malate dehydrogenase
    • ↵ a Important changes are shown in boldface. IND, indole.

  • TABLE 3.

    Changes in the expression of AI-2 uptake genes in E. coli O157:H7 biofilms after exposure to EPI and NE

    GeneBiological process descriptionRelative change in expression (n-fold) determined by the indicated methoda
    MicroarrayRT-PCR (EPI)
    EPINE
    lsrB AI-2 transporter −7.0 −5.3 −2.5
    lsrG Antibiotic biosynthesis −3.2 −3.0
    lsrD Transport −3.2 −1.4
    lsrA Transport −9.8 −5.3 −4.8
    lsrC Transport −4.3 −2.3 −2.4
    lsrK Carbohydrate metabolism −2.8 −2.3
    lsrR Regulation of transcription; DNA dependent −3.7 −3.7
    • ↵ a Values are based on an exposure of 7 h. Significant changes are in boldface.

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Differential Effects of Epinephrine, Norepinephrine, and Indole on Escherichia coli O157:H7 Chemotaxis, Colonization, and Gene Expression
Tarun Bansal, Derek Englert, Jintae Lee, Manjunath Hegde, Thomas K. Wood, Arul Jayaraman
Infection and Immunity Aug 2007, 75 (9) 4597-4607; DOI: 10.1128/IAI.00630-07

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Differential Effects of Epinephrine, Norepinephrine, and Indole on Escherichia coli O157:H7 Chemotaxis, Colonization, and Gene Expression
Tarun Bansal, Derek Englert, Jintae Lee, Manjunath Hegde, Thomas K. Wood, Arul Jayaraman
Infection and Immunity Aug 2007, 75 (9) 4597-4607; DOI: 10.1128/IAI.00630-07
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KEYWORDS

chemotaxis
Epinephrine
Escherichia coli O157
Gene Expression Regulation, Bacterial
Indoles
norepinephrine
signal transduction

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