Publications associées à Common and unique strategies of male killing evolved in two distinct Drosophila symbionts

Reproductive isolation arises during laboratory adaptation to a novel hot environment

Background: Reproductive isolation can result from adaptive processes (e.g., ecological speciation and mutation-order speciation) or stochastic processes such as "system drift" model. Ecological speciation predicts barriers to gene flow between populations ...

BMC2024

Host-derived organic acids enable gut colonization of the honey bee symbiont Snodgrassella alvi

Anders Meibom, Stéphane Laurent Escrig

Diverse bacteria can colonize the animal gut using dietary nutrients or by engaging in microbial crossfeeding interactions. Less is known about the role of host-derived nutrients in enabling gut bacterial colonization. Here we examined metabolic interactio ...

Nature Portfolio2024

Homogeneous Environmental Selection Structures the Bacterial Communities of Benthic Biofilms in Proglacial Floodplain Streams

Leïla Ezzat, Tom Ian Battin, Hannes Markus Peter, Jade Brandani, Tyler Joe Kohler, Stylianos Fodelianakis, Massimo Bourquin, Susheel Bhanu Busi, Grégoire Marie Octave Edouard Michoud

Streams draining proglacial floodplains harbor benthic biofilms comprised of diverse microbial communities. These high-mountain ecosystems are rapidly changing with climate warming, and it is therefore critical to better understand the mechanisms underlyin ...

AMER SOC MICROBIOLOGY2023

Energy-harnessing problem solving of primordial life: Modeling the emergence of catalytic host-nested parasite life cycles

Christian Iseli

All life forms on earth ultimately descended from a primordial population dubbed the last universal common ancestor or LUCA via Darwinian evolution. Extant living systems share two salient functional features, a metabolism extracting and transforming energ ...

2023

Antimicrobial susceptibility testing with integrated photonic crystal optical tweezers

Nicolas Villa

The abusive use of antimicrobial drugs during the last eighty years has favoured the natural selection of resistant pathogens able to neutralise drugs efficiently. Nowadays, antimicrobial resistance contributes to millions of deaths yearly, threatens the e ...

EPFL2023

Identification of Allobaculum mucolyticum as a novel human intestinal mucin degrader

Guido Van Mierlo

The human gut microbiota plays a central role in intestinal health and disease. Yet, many of its bacterial constituents are functionally still largely unexplored. A crucial prerequisite for bacterial survival and proliferation is the creation and/or exploi ...

2021

Rapid molecular evolution of Spiroplasma symbionts of Drosophila

Bruno Lemaitre, Florent François Masson

Spiroplasma is a genus of Mollicutes whose members include plant pathogens, insect pathogens and endosymbionts of animals. Spiroplasma phenotypes have been repeatedly observed to be spontaneously lost in Drosophila cultures, and several studies have docume ...

2021

The role of immune effectors in controlling Drosophila-microbes interactions

Alice Marra

All live beings are in constant interaction with microorganisms that may be beneficial, deleterious or commensal. Insects in particular live in close contact with microorganisms. This is especially true for species, like the fruit fly Drosophila melanogast ...

EPFL2021

Microfluidic culture platforms for C. elegans bacterial interaction and digestion studies at single-organism resolution

Vittorio Viri

Increasing interest in understanding fundamental biological processes, among which aging and nutrition, has led to the study of simple and powerful model organisms, as the round-worm Caenorhabditis elegans (C. elegans). The nematode, selected by Sydney Bre ...

EPFL2021

Blind killing of both male and female Drosophila embryos by a natural variant of the endosymbiotic bacterium Spiroplasma poulsonii

Bruno Lemaitre, Juan Camilo Paredes Escobar, Mario Gonzalo Garcia Arraez, Samuel Rommelaere, Florent François Masson

Spiroplasma poulsonii is a vertically transmitted endosymbiont of Drosophila melanogaster that causes male-killing, that is the death of infected male embryos during embryogenesis. Here, we report a natural variant of S. poulsonii that is efficiently verti ...

WILEY2020

Transformation of the Drosophila Sex-Manipulative Endosymbiont Spiroplasma poulsonii and Persisting Hurdles for Functional Genetic Studies

Bruno Lemaitre, Florent François Masson, Chloé Christiane Laurence Jollivet

Insects are frequently infected by bacterial symbionts that greatly affect their physiology and ecology. Most of these endosymbionts are, however, barely tractable outside their native host, rendering functional genetics studies difficult or impossible. Sp ...

AMER SOC MICROBIOLOGY2020

Tracking the cargo of extracellular symbionts into host tissues with correlated electron microscopy and nanoscale secondary ion mass spectrometry imaging

Anders Meibom, Stéphane Laurent Escrig, Stéphanie Kéren Cohen

Extracellular bacterial symbionts communicate biochemically with their hosts to establish niches that foster the partnership. Using quantitative ion microprobe isotopic imaging (nanoscale secondary ion mass spectrometry [NanoSIMS]), we surveyed localizatio ...

WILEY2020

Sub-cellular imaging shows reduced photosynthetic carbon and increased nitrogen assimilation by the non-native endosymbiontDurusdinium trenchiiin the model cnidarian Aiptasia

Anders Meibom

Hosting different symbiont species can affect inter-partner nutritional fluxes within the cnidarian-dinoflagellate symbiosis. Using nanoscale secondary ion mass spectrometry (NanoSIMS), we measured the spatial incorporation of photosynthetically fixed(13)C ...

WILEY2020

Functional analysis of RIP toxins from the Drosophila endosymbiont Spiroplasma poulsonii

Bruno Lemaitre, Juan Camilo Paredes Escobar, Mario Gonzalo Garcia Arraez, Florent François Masson

BackgroundInsects frequently live in close relationship with symbiotic bacteria that carry out beneficial functions for their host, like protection against parasites and viruses. However, in some cases, the mutualistic nature of such associations is put in ...

2019

Differential presentation of a single antimicrobial peptide is sufficient to identify LPS from distinct bacterial samples

Timothy Matthias Reichart

Rapid detection and identification of bacteria is important for human health, biodefense, and food safety. Small arrays of different antimicrobial peptides (AMPs) enable the identification of lipopolysaccharide (LPS) samples from a variety of bacterial spe ...

2019

Insights into flagellar function and mechanism from the squid-vibrio symbiosis

Stéphanie Kéren Cohen

Flagella are essential and multifunctional nanomachines that not only move symbionts towards their tissue colonization site, but also play multiple roles in communicating with the host. Thus, untangling the activities of flagella in reaching, interacting, ...

2019

Weevil pgrp-lb prevents endosymbiont TCT dissemination and chronic host systemic immune activation

Florent François Masson, João Pedro Alves Da Silva

Long-term intracellular symbiosis (or endosymbiosis) is widely distributed across invertebrates and is recognized as a major driving force in evolution. However, the maintenance of immune homeostasis in organisms chronically infected with mutualistic bacte ...

National Academy of Sciences2019

Elucidating regulatory mechanisms shaping the transcriptome and proteome of the gut immune response in Drosophila melanogaster

Michael Vincent Frochaux

Work on Drosophila melanogaster paved the way to our current understanding of modern genetics. Since then, this model organism has contributed greatly to various fields such as neurobiology, development, and immunology. The discovery and analysis of the va ...

EPFL2019

Single-cell studies of Mycobacterium smegmatis cell cycle using time-lapse fluorescence microscopy

Joëlle Xiao Yuan Ven

Cell division is one of the most primordial cellular processes and is essential for life propagation. It is composed of crucial events, namely genome duplication, chromosomes segregation and membrane separation. Failure of these processes will have dramati ...

EPFL2019

Commensal Gut Bacteria Buffer the Impact of Host Genetic Variants on Drosophila Developmental Traits under Nutritional Stress

Michael Vincent Frochaux, Bart Deplancke, Maroun Bou Sleiman, Virginie Sandra Braman, Maria Litovchenko

Eukaryotic genomes encode several buffering mechanisms that robustly maintain invariant phenotypic outcome despite fluctuating environmental conditions. Here we show that the Drosophila gut-associated commensals, represented by a single facultative symbion ...

2019