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  1. Article ; Online: Neutrophils are essential for containment of Vibrio cholerae to the intestine during the proinflammatory phase of infection.

    Queen, Jessica / Satchell, Karla J Fullner

    Infection and immunity

    2012  Volume 80, Issue 8, Page(s) 2905–2913

    Abstract: Cholera is classically considered a noninflammatory diarrheal disease, in comparison to invasive enteric organisms, although there is a low-level proinflammatory response during early infection with Vibrio cholerae and a strong proinflammatory reaction ... ...

    Abstract Cholera is classically considered a noninflammatory diarrheal disease, in comparison to invasive enteric organisms, although there is a low-level proinflammatory response during early infection with Vibrio cholerae and a strong proinflammatory reaction to live attenuated vaccine strains. Using an adult mouse intestinal infection model, this study examines the contribution of neutrophils to host defense to infection. Nontoxigenic El Tor O1 V. cholerae infection is characterized by the upregulation of interleukin-6 (IL-6), IL-10, and macrophage inflammatory protein 2 alpha in the intestine, indicating an acute innate immune response. Depletion of neutrophils from mice with anti-Ly6G IA8 monoclonal antibody led to decreased survival of mice. The role of neutrophils in protection of the host is to limit the infection to the intestine and control bacterial spread to extraintestinal organs. In the absence of neutrophils, the infection spread to the spleen and led to increased systemic levels of IL-1β and tumor necrosis factor alpha, suggesting the decreased survival in neutropenic mice is due to systemic shock. Neutrophils were found not to contribute to either clearance of colonizing bacteria or to alter the local immune response. However, when genes for secreted accessory toxins were deleted, the colonizing bacteria were cleared from the intestine, and this clearance is dependent upon neutrophils. Thus, the requirement for accessory toxins in virulence is negated in neutropenic mice, which is consistent with a role of accessory toxins in the evasion of innate immune cells in the intestine. Overall, these data support that neutrophils impact disease progression and suggest that neutrophil effectiveness can be manipulated through the deletion of accessory toxins.
    MeSH term(s) Animals ; Cholera/immunology ; Cholera/microbiology ; Cytokines/genetics ; Cytokines/metabolism ; Female ; Gene Expression Regulation/immunology ; Immunity, Innate ; Intestines/immunology ; Intestines/microbiology ; Mice ; Mice, Inbred C57BL ; Neutropenia/microbiology ; Neutrophils/physiology ; Vibrio cholerae/classification ; Vibrio cholerae/immunology ; Vibrio cholerae/metabolism ; Vibrio cholerae/pathogenicity ; Virulence
    Chemical Substances Cytokines
    Language English
    Publishing date 2012-05-21
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    DOI 10.1128/IAI.00356-12
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: MARTX, multifunctional autoprocessing repeats-in-toxin toxins.

    Satchell, Karla J Fullner

    Infection and immunity

    2007  Volume 75, Issue 11, Page(s) 5079–5084

    MeSH term(s) Bacterial Toxins/chemistry ; Bacterial Toxins/genetics ; Bacterial Toxins/toxicity ; Models, Biological ; Protein Structure, Tertiary ; Vibrio cholerae/genetics ; Vibrio cholerae/physiology
    Chemical Substances Bacterial Toxins ; RtxA protein, Vibrio cholerae
    Language English
    Publishing date 2007-11
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    DOI 10.1128/IAI.00525-07
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: MARTX, Multifunctional Autoprocessing Repeats-in-Toxin Toxins

    Satchell, Karla J. Fullner

    Infection and immunity IAI. 2007 Nov., v. 75, no. 11

    2007  

    Language English
    Dates of publication 2007-11
    Size p. 5079-5084.
    Publishing place American Society for Microbiology
    Document type Article
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Activation and suppression of the proinflammatory immune response by Vibrio cholerae toxins.

    Satchell, Karla J Fullner

    Microbes and infection

    2003  Volume 5, Issue 13, Page(s) 1241–1247

    Abstract: Vibrio cholerae induces either non-inflammatory diarrhea or inflammatory gastroenteritis, depending on the presence of cholera toxin, a fluid secretion inducer and a modulator of host immunity. In the absence of cholera toxin, other toxins induce ... ...

    Abstract Vibrio cholerae induces either non-inflammatory diarrhea or inflammatory gastroenteritis, depending on the presence of cholera toxin, a fluid secretion inducer and a modulator of host immunity. In the absence of cholera toxin, other toxins induce inflammation, resulting in gastroenteritis. Thus, multiple toxins likely affect the safety of live attenuated vaccines.
    MeSH term(s) Animals ; Cholera/immunology ; Cholera/physiopathology ; Cholera Toxin/pharmacology ; Cholera Vaccines/adverse effects ; Humans ; Immune System/drug effects ; Inflammation/etiology ; Vibrio cholerae/chemistry ; Vibrio cholerae/classification ; Vibrio cholerae/immunology ; Vibrio cholerae/pathogenicity
    Chemical Substances Cholera Vaccines ; Cholera Toxin (9012-63-9)
    Language English
    Publishing date 2003-11-04
    Publishing country France
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S. ; Review
    ZDB-ID 1465093-9
    ISSN 1769-714X ; 1286-4579
    ISSN (online) 1769-714X
    ISSN 1286-4579
    DOI 10.1016/j.micinf.2003.08.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Structure-function analysis of inositol hexakisphosphate-induced autoprocessing of the Vibrio cholerae multifunctional autoprocessing RTX toxin.

    Prochazkova, Katerina / Satchell, Karla J Fullner

    The Journal of biological chemistry

    2008  Volume 283, Issue 35, Page(s) 23656–23664

    Abstract: ... T., Jank, T., Satchell, K. J., and Aktories, K. (2007) J. Biol. Chem. 282, 25314-25321 ...

    Abstract Vibrio cholerae secretes a large virulence-associated multifunctional autoprocessing RTX toxin (MARTX(Vc)). Autoprocessing of this toxin by an embedded cysteine protease domain (CPD) is essential for this toxin to induce actin depolymerization in a broad range of cell types. A homologous CPD is also present in the large clostridial toxin TcdB and recent studies showed that inositol hexakisphosphate (Ins(1,2,3,4,5,6)P(6) or InsP(6)) stimulated the autoprocessing of TcdB dependent upon the CPD (Egerer, M., Giesemann, T., Jank, T., Satchell, K. J., and Aktories, K. (2007) J. Biol. Chem. 282, 25314-25321). In this work, the autoprocessing activity of the CPD within MARTX(Vc) is similarly found to be inducible by InsP(6). The CPD is shown to bind InsP(6) (K(d), 0.6 microm), and InsP(6) is shown to stimulate intramolecular autoprocessing at both physiological concentrations and as low as 0.01 microm. Processed CPD did not bind InsP(6) indicating that, subsequent to cleavage, the activated CPD may shift to an inactive conformation. To further pursue the mechanism of autoprocessing, conserved residues among 24 identified CPDs were mutagenized. In addition to cysteine and histidine residues that form the catalytic site, 2 lysine residues essential for InsP(6) binding and 5 lysine and arginine residues resulting in loss of activity at low InsP(6) concentrations were identified. Overall, our data support a model in which basic residues located across the CPD structure form an InsP(6) binding pocket and that the binding of InsP(6) stimulates processing by altering the CPD to an activated conformation. After processing, InsP(6) is shown to be recycled, while the cleaved CPD becomes incapable of further binding of InsP(6).
    MeSH term(s) Bacterial Toxins/chemistry ; Bacterial Toxins/genetics ; Bacterial Toxins/metabolism ; Catalytic Domain/physiology ; Cysteine Endopeptidases/chemistry ; Cysteine Endopeptidases/genetics ; Cysteine Endopeptidases/metabolism ; Models, Chemical ; Phytic Acid/chemistry ; Phytic Acid/metabolism ; Protein Binding/physiology ; Protein Structure, Tertiary/physiology ; Vibrio cholerae/enzymology ; Vibrio cholerae/genetics
    Chemical Substances Bacterial Toxins ; Phytic Acid (7IGF0S7R8I) ; Cysteine Endopeptidases (EC 3.4.22.-)
    Language English
    Publishing date 2008-06-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M803334200
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: RTX toxin actin cross-linking activity in clinical and environmental isolates of Vibrio cholerae.

    Cordero, Christina L / Sozhamannan, Shanmuga / Satchell, Karla J Fullner

    Journal of clinical microbiology

    2007  Volume 45, Issue 7, Page(s) 2289–2292

    Abstract: Vibrio cholerae strains from diverse O-antigen groups were evaluated for RTX toxin actin cross-linking activity. This study demonstrates that the actin cross-linking domain sequence is present within rtxA in the majority of clinical and environmental ... ...

    Abstract Vibrio cholerae strains from diverse O-antigen groups were evaluated for RTX toxin actin cross-linking activity. This study demonstrates that the actin cross-linking domain sequence is present within rtxA in the majority of clinical and environmental isolates tested, and the RTX toxin produced by these strains catalyzes the covalent cross-linking of cellular actin.
    MeSH term(s) Actins/metabolism ; Antigens, Bacterial/genetics ; Bacterial Toxins/isolation & purification ; Bacterial Toxins/pharmacology ; Cholera/microbiology ; Environment ; Humans ; Vibrio cholerae/genetics ; Vibrio cholerae/isolation & purification ; Vibrio cholerae/metabolism
    Chemical Substances Actins ; Antigens, Bacterial ; Bacterial Toxins
    Language English
    Publishing date 2007-07
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/JCM.00349-07
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Growth phase regulation of Vibrio cholerae RTX toxin export.

    Boardman, Bethany Kay / Meehan, Brian M / Fullner Satchell, Karla J

    Journal of bacteriology

    2007  Volume 189, Issue 5, Page(s) 1827–1835

    Abstract: Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, secretes several "accessory" toxins, including RTX toxin, which causes the cross-linking of the actin cytoskeleton. RTX toxin is exported to the extracellular milieu by an ... ...

    Abstract Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, secretes several "accessory" toxins, including RTX toxin, which causes the cross-linking of the actin cytoskeleton. RTX toxin is exported to the extracellular milieu by an atypical type I secretion system (T1SS), and we previously noted that RTX-associated activity is detectable only in supernatant fluids from log phase cultures. Here, we investigate the mechanisms for regulating RTX toxin activity in supernatant fluids. We find that exported proteases are capable of destroying RTX activity and may therefore play a role in the growth phase regulation of toxin activity. We determined that the absence of RTX toxin in stationary-phase culture supernatant fluids is also due to a lack of toxin secretion and not attributable to solely proteolytic degradation. We ascertained that the T1SS apparatus is regulated at the transcriptional level by growth phase control that is independent of quorum sensing, unlike other virulence factors of V. cholerae. Additionally, in stationary-phase cultures, all RTX toxin activity is associated with bacterial membranes or outer membrane vesicles.
    MeSH term(s) Bacterial Toxins/genetics ; Bacterial Toxins/metabolism ; Base Sequence ; Molecular Sequence Data ; Operon ; Promoter Regions, Genetic ; Protein Transport ; Quorum Sensing ; Transcription Initiation Site ; Transcription, Genetic ; Vibrio cholerae/growth & development ; Vibrio cholerae/pathogenicity
    Chemical Substances Bacterial Toxins
    Language English
    Publishing date 2007-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/JB.01766-06
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Autoprocessing of the Vibrio cholerae RTX toxin by the cysteine protease domain.

    Sheahan, Kerri-Lynn / Cordero, Christina L / Satchell, Karla J Fullner

    The EMBO journal

    2007  Volume 26, Issue 10, Page(s) 2552–2561

    Abstract: Vibrio cholerae RTX is a large multifunctional bacterial toxin that causes actin crosslinking. Due to its size, it was predicted to undergo proteolytic cleavage during translocation into host cells to deliver activity domains to the cytosol. In this ... ...

    Abstract Vibrio cholerae RTX is a large multifunctional bacterial toxin that causes actin crosslinking. Due to its size, it was predicted to undergo proteolytic cleavage during translocation into host cells to deliver activity domains to the cytosol. In this study, we identified a domain within the RTX toxin that is conserved in large clostridial glucosylating toxins TcdB, TcdA, TcnA, and TcsL; putative toxins from V. vulnificus, Yersinia sp., Photorhabdus sp., and Xenorhabdus sp.; and a filamentous/hemagglutinin-like protein FhaL from Bordetella sp. In vivo transfection studies and in vitro characterization of purified recombinant protein revealed that this domain from the V. cholerae RTX toxin is an autoprocessing cysteine protease whose activity is stimulated by the intracellular environment. A cysteine point mutation within the RTX holotoxin attenuated actin crosslinking activity suggesting that processing of the toxin is an important step in toxin translocation. Overall, we have uncovered a new mechanism by which large bacterial toxins and proteins deliver catalytic activities to the eukaryotic cell cytosol by autoprocessing after translocation.
    MeSH term(s) Amino Acid Sequence ; Animals ; Bacterial Toxins/chemistry ; Bacterial Toxins/genetics ; Bacterial Toxins/metabolism ; COS Cells ; Cercopithecus aethiops ; Consensus Sequence ; Cysteine Endopeptidases/chemistry ; Genes, Bacterial ; Hydrolysis ; Models, Biological ; Molecular Sequence Data ; Phylogeny ; Point Mutation ; Protein Structure, Tertiary ; Recombinant Proteins/chemistry ; Recombinant Proteins/metabolism ; Sequence Homology, Amino Acid ; Vibrio cholerae/chemistry ; Vibrio cholerae/genetics ; Vibrio cholerae/metabolism ; Vibrio cholerae/pathogenicity
    Chemical Substances Bacterial Toxins ; Recombinant Proteins ; Cysteine Endopeptidases (EC 3.4.22.-)
    Language English
    Publishing date 2007-05-16
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 586044-1
    ISSN 1460-2075 ; 0261-4189
    ISSN (online) 1460-2075
    ISSN 0261-4189
    DOI 10.1038/sj.emboj.7601700
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Inactivation of small Rho GTPases by the multifunctional RTX toxin from Vibrio cholerae.

    Sheahan, Kerri-Lynn / Satchell, Karla J Fullner

    Cellular microbiology

    2007  Volume 9, Issue 5, Page(s) 1324–1335

    Abstract: Many bacterial toxins target small Rho GTPases in order to manipulate the actin cytoskeleton. The depolymerization of the actin cytoskeleton by the Vibrio cholerae RTX toxin was previously identified to be due to the unique mechanism of covalent actin ... ...

    Abstract Many bacterial toxins target small Rho GTPases in order to manipulate the actin cytoskeleton. The depolymerization of the actin cytoskeleton by the Vibrio cholerae RTX toxin was previously identified to be due to the unique mechanism of covalent actin cross-linking. However, identification and subsequent deletion of the actin cross-linking domain within the RTX toxin revealed that this toxin has an additional cell rounding activity. In this study, we identified that the multifunctional RTX toxin also disrupts the actin cytoskeleton by causing the inactivation of small Rho GTPases, Rho, Rac and Cdc42. Inactivation of Rho by RTX was reversible in the presence of cycloheximide and by treatment of cells with CNF1 to constitutively activate Rho. These data suggest that RTX targets Rho GTPase regulation rather than affecting Rho GTPase directly. A novel 548-amino-acid region of RTX was identified to be responsible for the toxin-induced inactivation of the Rho GTPases. This domain did not carry GAP or phosphatase activities. Overall, these data show that the RTX toxin reversibly inactivates Rho GTPases by a mechanism distinct from other Rho-modifying bacterial toxins.
    MeSH term(s) Actins/metabolism ; Bacterial Toxins/genetics ; Bacterial Toxins/metabolism ; Bacterial Toxins/pharmacology ; Blotting, Western ; Cell Line, Tumor ; Cycloheximide/pharmacology ; Cytoskeleton/drug effects ; Cytoskeleton/metabolism ; Enzyme Activation/drug effects ; Escherichia coli Proteins/pharmacology ; GTPase-Activating Proteins/metabolism ; Green Fluorescent Proteins/genetics ; Green Fluorescent Proteins/metabolism ; Humans ; Microscopy, Fluorescence ; Microscopy, Phase-Contrast ; Monomeric GTP-Binding Proteins/antagonists & inhibitors ; Monomeric GTP-Binding Proteins/metabolism ; Phosphoric Monoester Hydrolases/metabolism ; Protein Structure, Tertiary/genetics ; Protein Structure, Tertiary/physiology ; Vibrio cholerae/metabolism ; cdc42 GTP-Binding Protein/metabolism ; rac GTP-Binding Proteins/metabolism ; rho GTP-Binding Proteins/antagonists & inhibitors ; rho GTP-Binding Proteins/metabolism
    Chemical Substances Actins ; Bacterial Toxins ; Escherichia coli Proteins ; GTPase-Activating Proteins ; cytotoxic necrotizing factor type 1 (106803-33-2) ; Green Fluorescent Proteins (147336-22-9) ; Cycloheximide (98600C0908) ; Phosphoric Monoester Hydrolases (EC 3.1.3.2) ; Monomeric GTP-Binding Proteins (EC 3.6.5.2) ; cdc42 GTP-Binding Protein (EC 3.6.5.2) ; rac GTP-Binding Proteins (EC 3.6.5.2) ; rho GTP-Binding Proteins (EC 3.6.5.2)
    Language English
    Publishing date 2007-05
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1468320-9
    ISSN 1462-5822 ; 1462-5814
    ISSN (online) 1462-5822
    ISSN 1462-5814
    DOI 10.1111/j.1462-5822.2006.00876.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Prolonged colonization of mice by Vibrio cholerae El Tor O1 depends on accessory toxins.

    Olivier, Verena / Salzman, Nita H / Satchell, Karla J Fullner

    Infection and immunity

    2007  Volume 75, Issue 10, Page(s) 5043–5051

    Abstract: Cholera epidemics caused by Vibrio cholerae El Tor O1 strains are typified by a large number of asymptomatic carriers who excrete vibrios but do not develop diarrhea. This carriage state was important for the spread of the seventh cholera pandemic as the ...

    Abstract Cholera epidemics caused by Vibrio cholerae El Tor O1 strains are typified by a large number of asymptomatic carriers who excrete vibrios but do not develop diarrhea. This carriage state was important for the spread of the seventh cholera pandemic as the bacterium was mobilized geographically, allowing the global dispersion of this less virulent strain. Virulence factors associated with the development of the carriage state have not been previously identified. We have developed an animal model of cholera in adult C57BL/6 mice wherein V. cholerae colonizes the mucus layer and forms microcolonies in the crypts of the distal small bowel. Colonization occurred 1 to 3 h after oral inoculation and peaked at 10 to 12 h, when bacterial loads exceeded the inoculum by 10- to 200-fold, indicating bacterial growth within the small intestine. After a clearance phase, the number of bacteria within the small intestine, but not those in the cecum or colon, stabilized and persisted for at least 72 h. The ability of V. cholerae to prevent clearance and establish this prolonged colonization was associated with the accessory toxins hemolysin, the multifunctional autoprocessing RTX toxin, and hemagglutinin/protease and did not require cholera toxin or toxin-coregulated pili. The defect in colonization attributed to the loss of the accessory toxins may be extracellularly complemented by inoculation of the defective strain with an isogenic colonization-proficient V. cholerae strain. This work thus demonstrates that secreted accessory toxins modify the host environment to enable prolonged colonization of the small intestine in the absence of overt disease symptoms and thereby contribute to disease dissemination via asymptomatic carriers.
    MeSH term(s) Animals ; Bacterial Proteins/genetics ; Bacterial Proteins/toxicity ; Bacterial Toxins/genetics ; Bacterial Toxins/toxicity ; Carrier State/microbiology ; Cholera/microbiology ; Cholera Toxin/genetics ; Cholera Toxin/toxicity ; Colony Count, Microbial ; Female ; Fimbriae, Bacterial ; Hemolysin Proteins/genetics ; Hemolysin Proteins/toxicity ; Intestines/microbiology ; Metalloendopeptidases/genetics ; Metalloendopeptidases/toxicity ; Mice ; Mice, Inbred C57BL ; Vibrio cholerae O1/growth & development ; Vibrio cholerae O1/pathogenicity ; Virulence Factors/genetics ; Virulence Factors/physiology
    Chemical Substances Bacterial Proteins ; Bacterial Toxins ; Hemolysin Proteins ; RtxA protein, Vibrio cholerae ; Virulence Factors ; hlyA protein, Vibrio cholerae ; Cholera Toxin (9012-63-9) ; Metalloendopeptidases (EC 3.4.24.-) ; hemagglutinin-protease (EC 3.4.24.-)
    Language English
    Publishing date 2007-10
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    DOI 10.1128/IAI.00508-07
    Database MEDical Literature Analysis and Retrieval System OnLINE

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