Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile.
The intestinal pathogen Clostridioides difficile exhibits heterogeneity in motility and toxin production. This phenotypic heterogeneity is achieved through phase variation by site-specific recombination via the DNA recombinase RecV, which reversibly inverts the "flagellar switch" upstream...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2020-08-01
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| Series: | PLoS Pathogens |
| Online Access: | https://doi.org/10.1371/journal.ppat.1008708 |
| _version_ | 1818361050131595264 |
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| author | Dominika Trzilova Brandon R Anjuwon-Foster Dariana Torres Rivera Rita Tamayo |
| author_facet | Dominika Trzilova Brandon R Anjuwon-Foster Dariana Torres Rivera Rita Tamayo |
| author_sort | Dominika Trzilova |
| collection | DOAJ |
| description | The intestinal pathogen Clostridioides difficile exhibits heterogeneity in motility and toxin production. This phenotypic heterogeneity is achieved through phase variation by site-specific recombination via the DNA recombinase RecV, which reversibly inverts the "flagellar switch" upstream of the flgB operon. A recV mutation prevents flagellar switch inversion and results in phenotypically locked strains. The orientation of the flagellar switch influences expression of the flgB operon post-transcription initiation, but the specific molecular mechanism is unknown. Here, we report the isolation and characterization of spontaneous suppressor mutants in the non-motile, non-toxigenic recV flg OFF background that regained motility and toxin production. The restored phenotypes corresponded with increased expression of flagellum and toxin genes. The motile suppressor mutants contained single-nucleotide polymorphisms (SNPs) in rho, which encodes the bacterial transcription terminator Rho factor. Analyses using transcriptional reporters indicate that Rho contributes to heterogeneity in flagellar gene expression by preferentially terminating transcription of flg OFF mRNA within the 5' leader sequence. Additionally, Rho is important for initial colonization of the intestine in a mouse model of infection, which may in part be due to the sporulation and growth defects observed in the rho mutants. Together these data implicate Rho factor as a regulator of gene expression affecting phase variation of important virulence factors of C. difficile. |
| first_indexed | 2024-12-13T21:10:31Z |
| format | Article |
| id | doaj.art-2255fc69ef704ee9ba65417a4b530c1e |
| institution | Directory Open Access Journal |
| issn | 1553-7366 1553-7374 |
| language | English |
| last_indexed | 2024-12-13T21:10:31Z |
| publishDate | 2020-08-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Pathogens |
| spelling | doaj.art-2255fc69ef704ee9ba65417a4b530c1e2022-12-21T23:31:21ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742020-08-01168e100870810.1371/journal.ppat.1008708Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile.Dominika TrzilovaBrandon R Anjuwon-FosterDariana Torres RiveraRita TamayoThe intestinal pathogen Clostridioides difficile exhibits heterogeneity in motility and toxin production. This phenotypic heterogeneity is achieved through phase variation by site-specific recombination via the DNA recombinase RecV, which reversibly inverts the "flagellar switch" upstream of the flgB operon. A recV mutation prevents flagellar switch inversion and results in phenotypically locked strains. The orientation of the flagellar switch influences expression of the flgB operon post-transcription initiation, but the specific molecular mechanism is unknown. Here, we report the isolation and characterization of spontaneous suppressor mutants in the non-motile, non-toxigenic recV flg OFF background that regained motility and toxin production. The restored phenotypes corresponded with increased expression of flagellum and toxin genes. The motile suppressor mutants contained single-nucleotide polymorphisms (SNPs) in rho, which encodes the bacterial transcription terminator Rho factor. Analyses using transcriptional reporters indicate that Rho contributes to heterogeneity in flagellar gene expression by preferentially terminating transcription of flg OFF mRNA within the 5' leader sequence. Additionally, Rho is important for initial colonization of the intestine in a mouse model of infection, which may in part be due to the sporulation and growth defects observed in the rho mutants. Together these data implicate Rho factor as a regulator of gene expression affecting phase variation of important virulence factors of C. difficile.https://doi.org/10.1371/journal.ppat.1008708 |
| spellingShingle | Dominika Trzilova Brandon R Anjuwon-Foster Dariana Torres Rivera Rita Tamayo Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. PLoS Pathogens |
| title | Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. |
| title_full | Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. |
| title_fullStr | Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. |
| title_full_unstemmed | Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. |
| title_short | Rho factor mediates flagellum and toxin phase variation and impacts virulence in Clostridioides difficile. |
| title_sort | rho factor mediates flagellum and toxin phase variation and impacts virulence in clostridioides difficile |
| url | https://doi.org/10.1371/journal.ppat.1008708 |
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