| 1. |
- Diard, Mederic, et al.
(författare)
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Inflammation boosts bacteriophage transfer between Salmonella spp.
- 2017
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 355:6330, s. 1211-1215
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Tidskriftsartikel (refereegranskat)abstract
- Bacteriophage transfer (lysogenic conversion) promotes bacterial virulence evolution. There is limited understanding of the factors that determine lysogenic conversion dynamics within infected hosts. Amurine Salmonella Typhimurium (S.Tm) diarrhea model was used to study the transfer of SopEF, a prophage from S.Tm SL1344, to S.Tm ATCC14028S. Gut inflammation and enteric disease triggered >55% lysogenic conversion of ATCC14028S within 3 days. Without inflammation, SopEF transfer was reduced by up to 10(5)-fold. This was because inflammation (e.g., reactive oxygen species, reactive nitrogen species, hypochlorite) triggers the bacterial SOS response, boosts expression of the phage antirepressor Tum, and thereby promotes free phage production and subsequent transfer. Mucosal vaccination prevented a dense intestinal S.Tm population from inducing inflammation and consequently abolished SopEF transfer. Vaccination may be a general strategy for blocking pathogen evolution that requires disease-driven transfer of temperate bacteriophages.
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| 2. |
- Giraud, Antoine, et al.
(författare)
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Dissecting the genetic components of adaptation of Escherichia coli to the mouse gut
- 2008
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Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- While pleiotropic adaptive mutations are thought to be central for evolution, little is known on the downstream molecular effects allowing adaptation to complex ecologically relevant environments. Here we show that Escherichia coli MG1655 adapts rapidly to the intestine of germ-free mice by single point mutations in EnvZ/OmpR two-component signal transduction system, which controls more than 100 genes. The selective advantage conferred by the mutations that modulate EnvZ/OmpR activities was the result of their independent and additive effects on flagellin expression and permeability. These results obtained in vivo thus suggest that global regulators may have evolved to coordinate activities that need to be fine-tuned simultaneously during adaptation to complex environments and that mutations in such regulators permit adjustment of the boundaries of physiological adaptation when switching between two very distinct environments.
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| 3. |
- Quax, Tessa E. F., et al.
(författare)
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Viruses of Microbes 2020 : The Latest Conquest on Viruses of Microbes
- 2021
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Ingår i: Viruses. - : MDPI. - 1999-4915. ; 13:5
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- This Special Issue celebrates viruses of microbes: those viruses that infect archaea, bacteria and microbial eukaryotes. This issue is associated with the 6th Viruses of Microbes (VoM) conference in Guimarães (www.vom2020.org, accessed on 1 April 2021), Portugal, that was originally planned for the summer of 2020, but has, in light of the pandemic, been postponed to 18–22 July 2022.
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