umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Type III Secretion Mediated Translocation of Effector Exoenzymes by Pseudomonas aeruginosa
Umeå University, Faculty of Medicine, Molecular Biology.
2003 (English)Doctoral thesis, comprehensive summary (Other academic)Alternative title
Injektion av gifter via typ III sekretionssystemet hos bakterien Pseudomonas aeruginosa (Swedish)
Place, publisher, year, edition, pages
2003. , 52 p.
Keyword [en]
Cell and molecular biology, Pseudomonas aeruginosa, type III secretion system, ExoS, ExoT, PcrV, PcrG, PopB, PopD, PopN, type IV pili
Keyword [sv]
Cell- och molekylärbiologi
National Category
Biochemistry and Molecular Biology
Research subject
Molecular Biology
Identifiers
URN: urn:nbn:se:umu:diva-174ISBN: 91-7305-545-X (print)OAI: oai:DiVA.org:umu-174DiVA: diva2:141908
Public defence
2003-11-28, Major Groove, 6L, Norrlands Universitetssjukhus, Umeå, 09:00 (English)
Opponent
Supervisors
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2010-02-24Bibliographically approved
List of papers
1. Type IV pili are not specifically required for contact dependent translocation of exoenzymes by Pseudomonas aeruginosa
Open this publication in new window or tab >>Type IV pili are not specifically required for contact dependent translocation of exoenzymes by Pseudomonas aeruginosa
Show others...
2002 In: Microbial Pathogenesis, ISSN 0882-4010, Vol. 33, no 6, 265-77 p.Article in journal (Refereed) Published
Abstract
Identifiers
urn:nbn:se:umu:diva-3306 (URN)
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2017-05-24Bibliographically approved
2. Polarised Type III Translocation of Effector Exoenzymes by Pseudomonas aeruginosa
Open this publication in new window or tab >>Polarised Type III Translocation of Effector Exoenzymes by Pseudomonas aeruginosa
In: Article in journal (Refereed) Submitted
Abstract
Identifiers
urn:nbn:se:umu:diva-3307 (URN)
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2017-05-24Bibliographically approved
3. Comparative analysis of type III effector translocation by Yersinia pseudotuberculosis expressing native LcrV or PcrV from Pseudomonas aeruginosa.
Open this publication in new window or tab >>Comparative analysis of type III effector translocation by Yersinia pseudotuberculosis expressing native LcrV or PcrV from Pseudomonas aeruginosa.
2003 (English)In: Journal of Infectious Diseases, ISSN 0022-1899, Vol. 188, no 2, 239-249 p.Article in journal (Refereed) Published
Abstract [en]

The homologues LcrV of Yersinia species and PcrV of Pseudomonas aeruginosa are pore-forming components. When expressed in a Yersinia lcrV background, PcrV formed smaller pores in infected erythrocyte membranes, correlating to a lowered translocation of Yersinia effectors. To understand this phenomenon, cytotoxins exoenzyme S of P. aeruginosa and YopE of Yersinia were introduced into a Yersinia background without Yop effectors but expressing LcrV or PcrV. Comparable translocation of each substrate indicated that substrate recognition by LcrV/PcrV is not a regulator of translocation. Yersinia harboring pcrV coexpressed with its native operon efficiently translocated effectors into HeLa cell monolayers and formed large LcrV-like pores in erythrocyte membranes. Thus, a PcrV complex with native P. aeruginosa translocon components is required to form fully functional pores for complete complementation of effector translocation in Yersinia.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-4144 (URN)10.1086/376452 (DOI)12854079 (PubMedID)
Available from: 2004-10-06 Created: 2004-10-06 Last updated: 2017-05-24Bibliographically approved
4. Exoenzyme T of Pseudomonas aeruginosa elicits cytotoxicity without interfering with Ras signal transduction
Open this publication in new window or tab >>Exoenzyme T of Pseudomonas aeruginosa elicits cytotoxicity without interfering with Ras signal transduction
Show others...
2001 (English)In: Cellular Microbiology, Vol. 3, no 4, 237-46 p.Article in journal (Refereed) Published
Abstract [en]

One virulence strategy used by the opportunistic pathogen Pseudomonas aeruginosa is to target toxic proteins into eukaryotic cells by a type III secretion mechanism. Two of these proteins, ExoS and ExoT, show 75% homology on amino acid level. However, compared with ExoS, ExoT exhibits highly reduced ADP-ribosylating activity and the role of ExoT in pathogenesis is poorly understood. To study the biological effect of ExoT, we used a strategy by which ExoT was delivered into host cells by the heterologous type III secretion system ofYersinia pseudotuberculosis. ExoT was found to induce a rounded cell morphology and to mediate disruption of actin microfilaments, similar to that induced by an ADP-ribosylation defective ExoS (E381A) and the related cytotoxin YopE of Y. pseudotuberculosis. In contrast to ExoS, ExoT had no major effect on cell viability and did not modify or inactivate Ras by ADP-ribosylation in vivo. However, similar to ExoS and YopE, ExoT exhibited GAP (GTPase activating protein) activity on RhoA GTPase in vitro. Interestingly, ExoT(R149K), deficient for GAP activity, still caused a morphological change of HeLa cells. Based on our findings, we suggest that the ADP-ribosylating activity of ExoT target another, as yet unidentified, host protein that is distinct from Ras.

Place, publisher, year, edition, pages
John Wiley & Sons, 2001
National Category
Cell and Molecular Biology
Identifiers
urn:nbn:se:umu:diva-3309 (URN)10.1046/j.1462-5822.2001.00108.x (DOI)
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2017-05-24Bibliographically approved
5. ADP-ribosylation by Exoenzyme T of Pseudomonas aeruginosa induces an irreversible effect on the host cell cytoskeleton in vivo
Open this publication in new window or tab >>ADP-ribosylation by Exoenzyme T of Pseudomonas aeruginosa induces an irreversible effect on the host cell cytoskeleton in vivo
In: Article in journal (Refereed) Submitted
Abstract
Identifiers
urn:nbn:se:umu:diva-3310 (URN)
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2017-05-24Bibliographically approved
6. Exoenzyme S shows selective ADP-ribosylation and GTPase-activating protein (GAP) activities towards small GTPases in vivo
Open this publication in new window or tab >>Exoenzyme S shows selective ADP-ribosylation and GTPase-activating protein (GAP) activities towards small GTPases in vivo
Show others...
2002 (English)In: Biochemical Journal, ISSN 0264-6021, E-ISSN 1470-8728, Vol. 367, no 3, 617-28 p.Article in journal (Refereed) Published
Abstract [en]

Intracellular targeting of the Pseudomonas aeruginosa toxins exoenzyme S (ExoS) and exoenzyme T (ExoT) initially results in disruption of the actin microfilament structure of eukaryotic cells. ExoS and ExoT are bifunctional cytotoxins, with N-terminal GTPase-activating protein (GAP) and C-terminal ADP-ribosyltransferase activities. We show that ExoS can modify multiple GTPases of the Ras superfamily in vivo. In contrast, ExoT shows no ADP-ribosylation activity towards any of the GTPases tested in vivo. We further examined ExoS targets in vivo and observed that ExoS modulates the activity of several of these small GTP-binding proteins, such as Ras, Rap1, Rap2, Ral, Rac1, RhoA and Cdc42. We suggest that ExoS is the major ADP-ribosyltransferase protein modulating small GTPase function encoded by P. aeruginosa. Furthermore, we show that the GAP activity of ExoS abrogates the activation of RhoA, Cdc42 and Rap1.

Keyword
bacterial toxin, cytotoxicity, cystic fibrosis, GTP-binding protein, Pseudomonas aeruginosa
National Category
Biochemistry and Molecular Biology
Identifiers
urn:nbn:se:umu:diva-3311 (URN)10.1042/BJ20020714 (DOI)
Available from: 2003-12-23 Created: 2003-12-23 Last updated: 2017-05-24Bibliographically approved

Open Access in DiVA

fulltext(1125 kB)1146 downloads
File information
File name FULLTEXT01.pdfFile size 1125 kBChecksum SHA-1
4c11645e5690ffa07c2f80842883e9ddc465bfef42d9f7ab462afdbb50687d16836c93a0
Type fulltextMimetype application/pdf

By organisation
Molecular Biology
Biochemistry and Molecular Biology

Search outside of DiVA

GoogleGoogle Scholar
Total: 1146 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 379 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf