The Monofunctional Catalase KatE of Xanthomonas axonopodis pv. citri Is Required for Full Virulence in Citrus Plants
Identifieur interne : 001214 ( Pmc/Curation ); précédent : 001213; suivant : 001215The Monofunctional Catalase KatE of Xanthomonas axonopodis pv. citri Is Required for Full Virulence in Citrus Plants
Auteurs : María Laura Tondo ; Silvana Petrocelli ; Jorgelina Ottado ; Elena G. OrellanoSource :
- PLoS ONE [ 1932-6203 ] ; 2010.
Abstract
Xac catalase activity was analyzed using native gel electrophoresis and semi-quantitative RT-PCR. We demonstrated that the catalase activity pattern was regulated in different growth stages displaying the highest levels during the stationary phase. KatE was the most active catalase in this phase of growth. At this stage cells were more resistant to hydrogen peroxide as was determined by the analysis of CFU after the exposition to different H2O2 concentrations. In addition, Xac exhibited an adaptive response to hydrogen peroxide, displaying higher levels of catalase activity and H2O2 resistance after treatment with sub-lethal concentrations of the oxidant. In the plant-like medium XVM2 the expression of KatE was strongly induced and in this medium Xac was more resistant to H2O2. A Xac
Our results confirmed that in contrast to other Xanthomonas species, Xac catalase-specific activity is induced during the stationary phase of growth in parallel with the bacterial resistance to peroxide challenge. Moreover, Xac catalases expression pattern is modified in response to any stimuli associated with the plant or the microenvironment it provides. The catalase KatE has been shown to have an important function for the colonization and survival of the bacterium in the citrus plant during the pathogenic process. Our work provides the first genetic evidence to support a monofunctional catalase as a virulence factor in Xac.
Url:
DOI: 10.1371/journal.pone.0010803
PubMed: 20520822
PubMed Central: 2875408
Links toward previous steps (curation, corpus...)
- to stream Pmc, to step Corpus: Pour aller vers cette notice dans l'étape Curation :001215
Links to Exploration step
PMC:2875408Le document en format XML
<record><TEI><teiHeader><fileDesc><titleStmt><title xml:lang="en">The Monofunctional Catalase KatE of <italic>Xanthomonas axonopodis</italic>
pv. <italic>citri</italic>
Is Required for Full Virulence in Citrus Plants</title>
<author><name sortKey="Tondo, Maria Laura" sort="Tondo, Maria Laura" uniqKey="Tondo M" first="María Laura" last="Tondo">María Laura Tondo</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Petrocelli, Silvana" sort="Petrocelli, Silvana" uniqKey="Petrocelli S" first="Silvana" last="Petrocelli">Silvana Petrocelli</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Ottado, Jorgelina" sort="Ottado, Jorgelina" uniqKey="Ottado J" first="Jorgelina" last="Ottado">Jorgelina Ottado</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Orellano, Elena G" sort="Orellano, Elena G" uniqKey="Orellano E" first="Elena G." last="Orellano">Elena G. Orellano</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
</titleStmt>
<publicationStmt><idno type="wicri:source">PMC</idno>
<idno type="pmid">20520822</idno>
<idno type="pmc">2875408</idno>
<idno type="url">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2875408</idno>
<idno type="RBID">PMC:2875408</idno>
<idno type="doi">10.1371/journal.pone.0010803</idno>
<date when="2010">2010</date>
<idno type="wicri:Area/Pmc/Corpus">001215</idno>
<idno type="wicri:Area/Pmc/Curation">001214</idno>
</publicationStmt>
<sourceDesc><biblStruct><analytic><title xml:lang="en" level="a" type="main">The Monofunctional Catalase KatE of <italic>Xanthomonas axonopodis</italic>
pv. <italic>citri</italic>
Is Required for Full Virulence in Citrus Plants</title>
<author><name sortKey="Tondo, Maria Laura" sort="Tondo, Maria Laura" uniqKey="Tondo M" first="María Laura" last="Tondo">María Laura Tondo</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Petrocelli, Silvana" sort="Petrocelli, Silvana" uniqKey="Petrocelli S" first="Silvana" last="Petrocelli">Silvana Petrocelli</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Ottado, Jorgelina" sort="Ottado, Jorgelina" uniqKey="Ottado J" first="Jorgelina" last="Ottado">Jorgelina Ottado</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
<author><name sortKey="Orellano, Elena G" sort="Orellano, Elena G" uniqKey="Orellano E" first="Elena G." last="Orellano">Elena G. Orellano</name>
<affiliation><nlm:aff id="aff1"></nlm:aff>
</affiliation>
</author>
</analytic>
<series><title level="j">PLoS ONE</title>
<idno type="eISSN">1932-6203</idno>
<imprint><date when="2010">2010</date>
</imprint>
</series>
</biblStruct>
</sourceDesc>
</fileDesc>
<profileDesc><textClass></textClass>
</profileDesc>
</teiHeader>
<front><div type="abstract" xml:lang="en"><sec><title>Background</title>
<p><italic>Xanthomonas axonopodis</italic>
pv. <italic>citri</italic>
(Xac) is an obligate aerobic phytopathogen constantly exposed to hydrogen peroxide produced by normal aerobic respiration and by the plant defense response during plant-pathogen interactions. Four putative catalase genes have been identified <italic>in silico</italic>
in the Xac genome, designated as <italic>katE</italic>
, <italic>catB</italic>
, <italic>srpA</italic>
(monofunctional catalases) and <italic>katG</italic>
(bifunctional catalase).</p>
</sec>
<sec><title>Methodology/Principal Findings</title>
<p>Xac catalase activity was analyzed using native gel electrophoresis and semi-quantitative RT-PCR. We demonstrated that the catalase activity pattern was regulated in different growth stages displaying the highest levels during the stationary phase. KatE was the most active catalase in this phase of growth. At this stage cells were more resistant to hydrogen peroxide as was determined by the analysis of CFU after the exposition to different H<sub>2</sub>
O<sub>2</sub>
concentrations. In addition, Xac exhibited an adaptive response to hydrogen peroxide, displaying higher levels of catalase activity and H<sub>2</sub>
O<sub>2</sub>
resistance after treatment with sub-lethal concentrations of the oxidant. In the plant-like medium XVM2 the expression of KatE was strongly induced and in this medium Xac was more resistant to H<sub>2</sub>
O<sub>2</sub>
. A Xac<italic>katE</italic>
mutant strain was constructed by insertional mutagenesis. We observed that catalase induction in stationary phase was lost meanwhile the adaptive response to peroxide was maintained in this mutant. Finally, the Xac<italic>katE</italic>
strain was assayed <italic>in planta</italic>
during host plant interaction rendering a less aggressive phenotype with a minor canker formation.</p>
</sec>
<sec><title>Conclusions</title>
<p>Our results confirmed that in contrast to other Xanthomonas species, Xac catalase-specific activity is induced during the stationary phase of growth in parallel with the bacterial resistance to peroxide challenge. Moreover, Xac catalases expression pattern is modified in response to any stimuli associated with the plant or the microenvironment it provides. The catalase KatE has been shown to have an important function for the colonization and survival of the bacterium in the citrus plant during the pathogenic process. Our work provides the first genetic evidence to support a monofunctional catalase as a virulence factor in Xac.</p>
</sec>
</div>
</front>
<back><div1 type="bibliography"><listBibl><biblStruct><analytic><author><name sortKey="Fridovich, I" uniqKey="Fridovich I">I Fridovich</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Imlay, Ja" uniqKey="Imlay J">JA Imlay</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Mccord, Jm" uniqKey="Mccord J">JM McCord</name>
</author>
<author><name sortKey="Fridovich, I" uniqKey="Fridovich I">I Fridovich</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Green, J" uniqKey="Green J">J Green</name>
</author>
<author><name sortKey="Paget, Ms" uniqKey="Paget M">MS Paget</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Imlay, Ja" uniqKey="Imlay J">JA Imlay</name>
</author>
<author><name sortKey="Linn, S" uniqKey="Linn S">S Linn</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Cabiscol, E" uniqKey="Cabiscol E">E Cabiscol</name>
</author>
<author><name sortKey="Tamarit, J" uniqKey="Tamarit J">J Tamarit</name>
</author>
<author><name sortKey="Ros, J" uniqKey="Ros J">J Ros</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Loewen, Pc" uniqKey="Loewen P">PC Loewen</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Chelikani, P" uniqKey="Chelikani P">P Chelikani</name>
</author>
<author><name sortKey="Fita, I" uniqKey="Fita I">I Fita</name>
</author>
<author><name sortKey="Loewen, Pc" uniqKey="Loewen P">PC Loewen</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Switala, J" uniqKey="Switala J">J Switala</name>
</author>
<author><name sortKey="Triggs Raine, Bl" uniqKey="Triggs Raine B">BL Triggs-Raine</name>
</author>
<author><name sortKey="Loewen, Pc" uniqKey="Loewen P">PC Loewen</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Brunings, Am" uniqKey="Brunings A">AM Brunings</name>
</author>
<author><name sortKey="Gabriel, Dw" uniqKey="Gabriel D">DW Gabriel</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Graham, Jh" uniqKey="Graham J">JH Graham</name>
</author>
<author><name sortKey="Gottwald, Tr" uniqKey="Gottwald T">TR Gottwald</name>
</author>
<author><name sortKey="Cubero, J" uniqKey="Cubero J">J Cubero</name>
</author>
<author><name sortKey="Achor, Ds" uniqKey="Achor D">DS Achor</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Baker, Cj" uniqKey="Baker C">CJ Baker</name>
</author>
<author><name sortKey="Orlandi, Ew" uniqKey="Orlandi E">EW Orlandi</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Grant, Jj" uniqKey="Grant J">JJ Grant</name>
</author>
<author><name sortKey="Loake, Gj" uniqKey="Loake G">GJ Loake</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Van Sluys, Ma" uniqKey="Van Sluys M">MA Van Sluys</name>
</author>
<author><name sortKey="Monteiro Vitorello, Cb" uniqKey="Monteiro Vitorello C">CB Monteiro-Vitorello</name>
</author>
<author><name sortKey="Camargo, Le" uniqKey="Camargo L">LE Camargo</name>
</author>
<author><name sortKey="Menck, Cf" uniqKey="Menck C">CF Menck</name>
</author>
<author><name sortKey="Da Silva, Ac" uniqKey="Da Silva A">AC da Silva</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Da Silva, Ac" uniqKey="Da Silva A">AC da Silva</name>
</author>
<author><name sortKey="Ferro, Ja" uniqKey="Ferro J">JA Ferro</name>
</author>
<author><name sortKey="Reinach, Fc" uniqKey="Reinach F">FC Reinach</name>
</author>
<author><name sortKey="Farah, Cs" uniqKey="Farah C">CS Farah</name>
</author>
<author><name sortKey="Furlan, Lr" uniqKey="Furlan L">LR Furlan</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Sambrook, J" uniqKey="Sambrook J">J Sambrook</name>
</author>
<author><name sortKey="Fritsch, Ef" uniqKey="Fritsch E">EF Fritsch</name>
</author>
<author><name sortKey="Maniatis, T" uniqKey="Maniatis T">T Maniatis</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Sedmack, Jj" uniqKey="Sedmack J">JJ Sedmack</name>
</author>
<author><name sortKey="Grossberg, Se" uniqKey="Grossberg S">SE Grossberg</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Beers, Rf" uniqKey="Beers R">RF Beers</name>
</author>
<author><name sortKey="Sizer, Iw" uniqKey="Sizer I">IW Sizer</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Scandalios, Jg" uniqKey="Scandalios J">JG Scandalios</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Murray, Mg" uniqKey="Murray M">MG Murray</name>
</author>
<author><name sortKey="Thompson, Wf" uniqKey="Thompson W">WF Thompson</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Simon, R" uniqKey="Simon R">R Simon</name>
</author>
<author><name sortKey="Priefer, U" uniqKey="Priefer U">U Priefer</name>
</author>
<author><name sortKey="Puhler, A" uniqKey="Puhler A">A Pühler</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Dunger, G" uniqKey="Dunger G">G Dunger</name>
</author>
<author><name sortKey="Arabolaza, Ln" uniqKey="Arabolaza L">LN Arabolaza</name>
</author>
<author><name sortKey="Gottig, N" uniqKey="Gottig N">N Gottig</name>
</author>
<author><name sortKey="Orellano, Eg" uniqKey="Orellano E">EG Orellano</name>
</author>
<author><name sortKey="Ottado, J" uniqKey="Ottado J">J Ottado</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Wengelnik, K" uniqKey="Wengelnik K">K Wengelnik</name>
</author>
<author><name sortKey="Bonas, U" uniqKey="Bonas U">U Bonas</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Katzen, F" uniqKey="Katzen F">F Katzen</name>
</author>
<author><name sortKey="Becker, A" uniqKey="Becker A">A Becker</name>
</author>
<author><name sortKey="Ielmini, Mv" uniqKey="Ielmini M">MV Ielmini</name>
</author>
<author><name sortKey="Oddo, Cg" uniqKey="Oddo C">CG Oddo</name>
</author>
<author><name sortKey="Ielpi, L" uniqKey="Ielpi L">L Ielpi</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Kovach, Me" uniqKey="Kovach M">ME Kovach</name>
</author>
<author><name sortKey="Elzer, Ph" uniqKey="Elzer P">PH Elzer</name>
</author>
<author><name sortKey="Hill, Ds" uniqKey="Hill D">DS Hill</name>
</author>
<author><name sortKey="Robertson, Gt" uniqKey="Robertson G">GT Robertson</name>
</author>
<author><name sortKey="Farris, Ma" uniqKey="Farris M">MA Farris</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Thompson, Jd" uniqKey="Thompson J">JD Thompson</name>
</author>
<author><name sortKey="Gibson, Tj" uniqKey="Gibson T">TJ Gibson</name>
</author>
<author><name sortKey="Plewniak, F" uniqKey="Plewniak F">F Plewniak</name>
</author>
<author><name sortKey="Jeanmougin, F" uniqKey="Jeanmougin F">F Jeanmougin</name>
</author>
<author><name sortKey="Higgins, Dg" uniqKey="Higgins D">DG Higgins</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Mongkolsuk, S" uniqKey="Mongkolsuk S">S Mongkolsuk</name>
</author>
<author><name sortKey="Vattanaviboon, P" uniqKey="Vattanaviboon P">P Vattanaviboon</name>
</author>
<author><name sortKey="Praitaun, W" uniqKey="Praitaun W">W Praitaun</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Chamnongpol, S" uniqKey="Chamnongpol S">S Chamnongpol</name>
</author>
<author><name sortKey="Mongkolsuk, S" uniqKey="Mongkolsuk S">S Mongkolsuk</name>
</author>
<author><name sortKey="Vattanaviboon, P" uniqKey="Vattanaviboon P">P Vattanaviboon</name>
</author>
<author><name sortKey="Fuangthong, M" uniqKey="Fuangthong M">M Fuangthong</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Vattanaviboon, P" uniqKey="Vattanaviboon P">P Vattanaviboon</name>
</author>
<author><name sortKey="Mongkolsuk, S" uniqKey="Mongkolsuk S">S Mongkolsuk</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Chauvatcharin, N" uniqKey="Chauvatcharin N">N Chauvatcharin</name>
</author>
<author><name sortKey="Vattanaviboon, P" uniqKey="Vattanaviboon P">P Vattanaviboon</name>
</author>
<author><name sortKey="Switala, J" uniqKey="Switala J">J Switala</name>
</author>
<author><name sortKey="Loewen, Pc" uniqKey="Loewen P">PC Loewen</name>
</author>
<author><name sortKey="Mongkolsuk, S" uniqKey="Mongkolsuk S">S Mongkolsuk</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Klotz, Mg" uniqKey="Klotz M">MG Klotz</name>
</author>
<author><name sortKey="Hutcheson, Sw" uniqKey="Hutcheson S">SW Hutcheson</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Hanyu, M" uniqKey="Hanyu M">M Hanyu</name>
</author>
<author><name sortKey="Fujimoto, H" uniqKey="Fujimoto H">H Fujimoto</name>
</author>
<author><name sortKey="Tejima, K" uniqKey="Tejima K">K Tejima</name>
</author>
<author><name sortKey="Saeki, K" uniqKey="Saeki K">K Saeki</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Koebnik, R" uniqKey="Koebnik R">R Koebnik</name>
</author>
<author><name sortKey="Kruger, A" uniqKey="Kruger A">A Kruger</name>
</author>
<author><name sortKey="Thieme, F" uniqKey="Thieme F">F Thieme</name>
</author>
<author><name sortKey="Urban, A" uniqKey="Urban A">A Urban</name>
</author>
<author><name sortKey="Bonas, U" uniqKey="Bonas U">U Bonas</name>
</author>
</analytic>
</biblStruct>
<biblStruct><analytic><author><name sortKey="Jittawuttipoka, T" uniqKey="Jittawuttipoka T">T Jittawuttipoka</name>
</author>
<author><name sortKey="Buranajitpakorn, S" uniqKey="Buranajitpakorn S">S Buranajitpakorn</name>
</author>
<author><name sortKey="Vattanaviboon, P" uniqKey="Vattanaviboon P">P Vattanaviboon</name>
</author>
<author><name sortKey="Mongkolsuk, S" uniqKey="Mongkolsuk S">S Mongkolsuk</name>
</author>
</analytic>
</biblStruct>
</listBibl>
</div1>
</back>
</TEI>
<pmc article-type="research-article"><pmc-dir>properties open_access</pmc-dir>
<front><journal-meta><journal-id journal-id-type="nlm-ta">PLoS One</journal-id>
<journal-id journal-id-type="publisher-id">plos</journal-id>
<journal-id journal-id-type="pmc">plosone</journal-id>
<journal-title-group><journal-title>PLoS ONE</journal-title>
</journal-title-group>
<issn pub-type="epub">1932-6203</issn>
<publisher><publisher-name>Public Library of Science</publisher-name>
<publisher-loc>San Francisco, USA</publisher-loc>
</publisher>
</journal-meta>
<article-meta><article-id pub-id-type="pmid">20520822</article-id>
<article-id pub-id-type="pmc">2875408</article-id>
<article-id pub-id-type="publisher-id">10-PONE-RA-15447R1</article-id>
<article-id pub-id-type="doi">10.1371/journal.pone.0010803</article-id>
<article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject>
</subj-group>
<subj-group subj-group-type="Discipline"><subject>Microbiology</subject>
<subject>Microbiology/Microbial Growth and Development</subject>
<subject>Microbiology/Microbial Physiology and Metabolism</subject>
<subject>Microbiology/Plant-Biotic Interactions</subject>
</subj-group>
</article-categories>
<title-group><article-title>The Monofunctional Catalase KatE of <italic>Xanthomonas axonopodis</italic>
pv. <italic>citri</italic>
Is Required for Full Virulence in Citrus Plants</article-title>
<alt-title alt-title-type="running-head">Catalases from <italic>Xanthomonas</italic>
</alt-title>
</title-group>
<contrib-group><contrib contrib-type="author"><name><surname>Tondo</surname>
<given-names>María Laura</given-names>
</name>
<xref ref-type="aff" rid="aff1"></xref>
</contrib>
<contrib contrib-type="author"><name><surname>Petrocelli</surname>
<given-names>Silvana</given-names>
</name>
<xref ref-type="aff" rid="aff1"></xref>
</contrib>
<contrib contrib-type="author"><name><surname>Ottado</surname>
<given-names>Jorgelina</given-names>
</name>
<xref ref-type="aff" rid="aff1"></xref>
</contrib>
<contrib contrib-type="author"><name><surname>Orellano</surname>
<given-names>Elena G.</given-names>
</name>
<xref ref-type="aff" rid="aff1"></xref>
<xref ref-type="corresp" rid="cor1"><sup>*</sup>
</xref>
</contrib>
</contrib-group>
<aff id="aff1"><addr-line>Molecular Biology Division, Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario, Rosario, Argentina</addr-line>
</aff>
<contrib-group><contrib contrib-type="editor"><name><surname>Yang</surname>
<given-names>Ching-Hong</given-names>
</name>
<role>Editor</role>
<xref ref-type="aff" rid="edit1"></xref>
</contrib>
</contrib-group>
<aff id="edit1">University of Wisconsin-Milwaukee, United States of America</aff>
<author-notes><corresp id="cor1">* E-mail: <email>orellano@ibr.gov.ar</email>
</corresp>
<fn fn-type="con"><p>Conceived and designed the experiments: MLT JO EGO. Performed the experiments: MLT SP. Analyzed the data: MLT JO EGO. Contributed reagents/materials/analysis tools: JO EGO. Wrote the paper: MLT EGO.</p>
</fn>
</author-notes>
<pub-date pub-type="collection"><year>2010</year>
</pub-date>
<pub-date pub-type="epub"><day>24</day>
<month>5</month>
<year>2010</year>
</pub-date>
<volume>5</volume>
<issue>5</issue>
<elocation-id>e10803</elocation-id>
<history><date date-type="received"><day>10</day>
<month>1</month>
<year>2010</year>
</date>
<date date-type="accepted"><day>22</day>
<month>4</month>
<year>2010</year>
</date>
</history>
<permissions><copyright-statement>Tondo et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</copyright-statement>
</permissions>
<abstract><sec><title>Background</title>
<p><italic>Xanthomonas axonopodis</italic>
pv. <italic>citri</italic>
(Xac) is an obligate aerobic phytopathogen constantly exposed to hydrogen peroxide produced by normal aerobic respiration and by the plant defense response during plant-pathogen interactions. Four putative catalase genes have been identified <italic>in silico</italic>
in the Xac genome, designated as <italic>katE</italic>
, <italic>catB</italic>
, <italic>srpA</italic>
(monofunctional catalases) and <italic>katG</italic>
(bifunctional catalase).</p>
</sec>
<sec><title>Methodology/Principal Findings</title>
<p>Xac catalase activity was analyzed using native gel electrophoresis and semi-quantitative RT-PCR. We demonstrated that the catalase activity pattern was regulated in different growth stages displaying the highest levels during the stationary phase. KatE was the most active catalase in this phase of growth. At this stage cells were more resistant to hydrogen peroxide as was determined by the analysis of CFU after the exposition to different H<sub>2</sub>
O<sub>2</sub>
concentrations. In addition, Xac exhibited an adaptive response to hydrogen peroxide, displaying higher levels of catalase activity and H<sub>2</sub>
O<sub>2</sub>
resistance after treatment with sub-lethal concentrations of the oxidant. In the plant-like medium XVM2 the expression of KatE was strongly induced and in this medium Xac was more resistant to H<sub>2</sub>
O<sub>2</sub>
. A Xac<italic>katE</italic>
mutant strain was constructed by insertional mutagenesis. We observed that catalase induction in stationary phase was lost meanwhile the adaptive response to peroxide was maintained in this mutant. Finally, the Xac<italic>katE</italic>
strain was assayed <italic>in planta</italic>
during host plant interaction rendering a less aggressive phenotype with a minor canker formation.</p>
</sec>
<sec><title>Conclusions</title>
<p>Our results confirmed that in contrast to other Xanthomonas species, Xac catalase-specific activity is induced during the stationary phase of growth in parallel with the bacterial resistance to peroxide challenge. Moreover, Xac catalases expression pattern is modified in response to any stimuli associated with the plant or the microenvironment it provides. The catalase KatE has been shown to have an important function for the colonization and survival of the bacterium in the citrus plant during the pathogenic process. Our work provides the first genetic evidence to support a monofunctional catalase as a virulence factor in Xac.</p>
</sec>
</abstract>
<counts><page-count count="11"></page-count>
</counts>
</article-meta>
</front>
</pmc>
</record>
Pour manipuler ce document sous Unix (Dilib)
EXPLOR_STEP=$WICRI_ROOT/Wicri/Bois/explor/OrangerV1/Data/Pmc/Curation
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 001214 | SxmlIndent | more
Ou
HfdSelect -h $EXPLOR_AREA/Data/Pmc/Curation/biblio.hfd -nk 001214 | SxmlIndent | more
Pour mettre un lien sur cette page dans le réseau Wicri
{{Explor lien |wiki= Wicri/Bois |area= OrangerV1 |flux= Pmc |étape= Curation |type= RBID |clé= PMC:2875408 |texte= The Monofunctional Catalase KatE of Xanthomonas axonopodis pv. citri Is Required for Full Virulence in Citrus Plants }}
Pour générer des pages wiki
HfdIndexSelect -h $EXPLOR_AREA/Data/Pmc/Curation/RBID.i -Sk "pubmed:20520822" \ | HfdSelect -Kh $EXPLOR_AREA/Data/Pmc/Curation/biblio.hfd \ | NlmPubMed2Wicri -a OrangerV1
This area was generated with Dilib version V0.6.25. |