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
Identification of specific sequence motif of YopN of Yersinia pseudotuberculosis required for systemic infection
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
2019 (English)In: Virulence, ISSN 2150-5594, E-ISSN 2150-5608, Vol. 10, no 1, p. 10-25Article in journal (Refereed) Published
Abstract [en]

Type III secretion systems (T3SSs) are tightly regulated key virulence mechanisms shared by many Gram-negative pathogens. YopN, one of the substrates, is also crucial in regulation of expression, secretion and activation of the T3SS of pathogenic Yersinia species. Interestingly, YopN itself is also targeted into host cells but so far no activity or direct role for YopN inside host cells has been described. Recently, we were able show that the central region of YopN is required for efficient translocation of YopH and YopE into host cells. This was also shown to impact the ability of Yersinia to block phagocytosis. One difficulty in studying YopN is to generate mutants that are not impaired in regulation of the T3SS. In this study we extended our previous work and were able to generate specific mutants within the central region of YopN. These mutants were predicted to be crucial for formation of a putative coiled-coil domain (CCD). Similar to the previously described deletion mutant of the central region, these mutants were all impaired in translocation of YopE and YopH. Interestingly, these YopN variants were not translocated into host cells. Importantly, when these mutants were introduced in cis on the virulence plasmid, they retained full regulatory function of T3SS expression and secretion. This allowed us to evaluate one of the mutants, yopNGAGA, in the systemic mouse infection model. Using in vivo imaging technology we could verify that the mutant was also attenuated in vivo and highly impaired to establish systemic infection.

Place, publisher, year, edition, pages
Taylor & Francis, 2019. Vol. 10, no 1, p. 10-25
Keywords [en]
Yersinia, T3SS, YopN, mouse infection, virulence
National Category
Microbiology in the medical area
Identifiers
URN: urn:nbn:se:umu:diva-154803DOI: 10.1080/21505594.2018.1551709ISI: 000453038200001PubMedID: 30488778Scopus ID: 2-s2.0-85058611719OAI: oai:DiVA.org:umu-154803DiVA, id: diva2:1275959
Funder
The Kempe Foundations, 161121Swedish Research Council, 2011-3439Available from: 2019-01-07 Created: 2019-01-07 Last updated: 2019-01-09Bibliographically approved
In thesis
1. Multiple functions of YopN in the Yersinia pseudotuberculosis type III secretion system: from regulation to in vivo infection
Open this publication in new window or tab >>Multiple functions of YopN in the Yersinia pseudotuberculosis type III secretion system: from regulation to in vivo infection
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The type 3 secretion systems (T3SSs) are virulence mechanisms used by various Gram-negative bacteria to overcome the host immunity. They are often target-cell contact induced and activated. Activation results in targeting of virulence effector substrates into host cells. One class of secreted substrates, translocators, are required for the intracellular targeting of the second class, the virulence effectors, into host target cells. T3SSs are mainly regulated at 2 levels; a shift from environmental to host temperature results in low level induction of the system whereas target cell contact further induces and activates the system. In the Yersinia T3SS, YopN, one of the secreted substrates, is involved in the latter level of activation. Under non-inducing conditions, YopN complexes with TyeA, SycN and YscB and this complex suppresses the T3SS via an unknown mechanism. When the system is induced, the complex is believed to dissociate and YopN is secreted resulting in the activation of the system. Earlier studies indicated that YopN is not only secreted but also translocated into target cells in a T3SS dependent manner. TyeA, SycN and YscB bind to the C-terminal and N-terminal YopN respectively but so far the central region (CR) of YopN has not been characterized. In this study we have focused on the function of the YopN central region.

We therefore generated in-frame deletion mutants within the CR of YopN. One of these deletion mutants, aa 76-181, showed decreased early translocation of both YopE and YopH into infected host cells and also failed to efficiently block phagocytosis by macrophages. However, the YopNΔ76-181 protein was expressed at lower levels compared to wt YopN and also showed a slightly deregulated phenotype when expressed from its native promoter and were as a consequence not possible to use in in vivo infection studies.

Therefore, we generated mutants that disrupted a putative coiled coil domain located at the very N-terminal of CR. Similar to YopNΔ76-181, these substitution mutants were affected in the early translocation of effector proteins. Importantly, they were as stable as wt YopN when expressed from the native promoter. One of these mutants was unable to cause systemic infection in mice indicating that YopN indeed also has a direct role in virulence and is required for establishment of systemic infection in vivo.

Place, publisher, year, edition, pages
Umeå: Umeå University, 2019. p. 88
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 2007
Keywords
Type III secretion system, Yersinia, YopN, virulence, phagocytosis, mouse infection, secretion kinetics
National Category
Biochemistry and Molecular Biology Microbiology
Identifiers
urn:nbn:se:umu:diva-155193 (URN)978-91-7601-996-2 (ISBN)
Public defence
2019-02-01, Major Groove, Building 6L, NUS, Umeå, 09:00 (English)
Opponent
Supervisors
Available from: 2019-01-11 Created: 2019-01-09 Last updated: 2019-01-11Bibliographically approved

Open Access in DiVA

fulltext(2373 kB)66 downloads
File information
File name FULLTEXT01.pdfFile size 2373 kBChecksum SHA-512
7142ba8f707ca8e3ae8c9d4fc7db57b7171d7c9851130ae3f0a57dc9abb5cb64ba3042d1a7d5fb502d1e0d54d0a57f2bd4ac13ba75b808d98c2a228b118943bf
Type fulltextMimetype application/pdf

Other links

Publisher's full textPubMedScopus

Authority records BETA

Bamyaci, SarpNordfelth, RolandForsberg, Åke

Search in DiVA

By author/editor
Bamyaci, SarpNordfelth, RolandForsberg, Åke
By organisation
Department of Molecular Biology (Faculty of Medicine)Umeå Centre for Microbial Research (UCMR)Molecular Infection Medicine Sweden (MIMS)Department of Molecular Biology (Faculty of Science and Technology)
In the same journal
Virulence
Microbiology in the medical area

Search outside of DiVA

GoogleGoogle Scholar
Total: 66 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

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 528 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