Autor(es): Ameline, Camille ; Seixas, Elsa ; Barreto, Hugo C. ; Frazão, Nelson ; Rodrigues, Miguel V. ; Ventura, M. Rita ; Lourenço, Marta ; Gordo, Isabel
Data: 2025
Identificador Persistente: http://hdl.handle.net/10362/189103
Origem: Repositório Institucional da UNL
Assunto(s): Parasitology; Microbiology; Immunology; Molecular Biology; Genetics; Virology; SDG 3 - Good Health and Well-being
Funding Information: Funding was provided by the project PTDC/BIA-EVL/7546/2020, from the Funda\u00E7\u00E3o para a Ci\u00EAncia e Tecnologia (FCT) to I.G, NF and ES. CA is funded by a Swiss National Science Foundation (SNSF) Postdoc.Mobility fellowship P500PB_206642, NF by the work contract IGC-DL57NT-26, under the contract-program between FCT, and ES by Project PTDC/BIA-EVL/7546/2020 from FCT. H.C.B. was supported by DREAM ANR-20-AMR-0002 grant, and by the HORIZON-MSCA-2023-PF-01 project number 101148351 - MICROINVADER, funded by the European Union. Views and opinions expressed are however those of the author only and do not necessarily reflect those of the European Union or the European Research Executive Agency. This work was supported by grant ERC-2022-ADG 101096203 EvoInHi to I.G., funded by the European Union. Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or ERC. Neither the European Union nor the granting authority can be held responsible for them. This work was developed with the support from the research infrastructure CONGENTO, co-financed by Lisboa Regional Operational Programme (Lisboa2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) and Funda\u00E7\u00E3o para a Ci\u00EAncia e Tecnologia (Portugal) under the project LISBOA-01-0145-FEDER-022170 to I.G.. The work of the chemical synthesis of Fructoselysine was supported by Fundacao para a Ciencia e Tecnologia (FCT): PhD fellowship 2022.09426. BD to M.V.R., MOSTMICRO-ITQB R&D Unit (UIDB/04612/2020, UIDP/04612/2020) to M.R.V. and LS4FUTURE Associated Laboratory (LA/P/0087/2020) to M.R.V.. The NMR data was acquired at CERMAX, ITQB-NOVA, Oeiras, Portugal with equipment funded by FCT, project AAC 01/SAICT/2016 to M.R.V. The funders played no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Publisher Copyright: © 2025 Ameline 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.
Escherichia coli is a commensal of the intestine of most mammals, but also an important human pathogen. Within a healthy human its population structure is highly dynamic, where typically a dominant E. coli strain is accompanied by several low abundance satellite strains. However, the factors underlying E. coli strain dynamics and evolution within hosts are still poorly understood. Here, we colonised germ-free immune-competent (wild-type) or immune-compromised (Rag2KO) mice, with two phylogenetically distinct strains of E. coli, to determine if strain co-existence and within-strain evolution are shaped by the adaptive immune system. Irrespectively of the immune status of the mice one strain reaches a 100-fold larger abundance than the other. However, the abundance of the dominant strain is significantly higher in Rag2KO mice. Strains co-exist for thousands of generations and accumulate beneficial mutations in genes coding for different resource preferences. A higher rate of mutation accumulation in immune-compromised vs. immune-competent mice is observed and adaptative mutations specific to immune-competent mice are identified. Importantly, the presence of the adaptive immune system selects for mutations that increase stress resistance and the dynamics of such evolutionary events associates with the onset of an antibody response.
