Who are we ?
Who are we ?
We are researchers recently recruited at the IMM (Institut de Microbiologie de la Méditerranée) in Marseille. After many years doing research abroad, we realized how important and beneficial a collaborative network in France can be.
This is why we created µNet-Marseille.
µNet aims to build a community of scientists who are passionate and want to share about about their research work.
Clémentine Delan-Forino (Galinier lab - Laboratoire de Chimie Bactérienne, UMR 7283)
I am interested in studying RNAs in microorganisms.
During my PhD (Maurel Lab, Paris-Sorbonne), I worked on characterizing Viroid small RNAs that are infectious pathogens of plants. As a post-doc (Tollervey lab in Edinburgh), I studied how two complexes (Exosome and TRAMP) responsible for RNA processing in S. cerevisiae, cooperate to specifically recognize target RNAs. Since my recruitment (in 2021) as a CR CN by the CNRS, I work on understanding how B. subtilis small non-coding RNAs, known to be major post-transcriptional regulators, coordinate key physiological processes (such as morphogenesis, cell division and sporulation) with nutrient availability. In combination with molecular biology and microscopy, I am developing a UV-based high throughput cross-linking method to characterize RNA-RNA and RNA-protein interactions. Overall, my project aims to shed light on B. subtilis sRNA-based network and characterize its role in the regulation of carbon metabolism and B. subtilis life cycle.
Nicolas Vita (Fierobe lab - Laboratoire de Chimie Bactérienne, UMR 7283)
Since my PhD, my interest has been focusing on the characterization of different anaerobic processes at the molecular and cellular level. By combining biochemical and biophysical approaches, molecular biology, genetic and synthetic biology, I studied the biosynthesis of central metabolic metallo-enzymes, their protection against the oxidative stress, the anaerobic plant biomass degradation and its sustainable biotechnological potential (i.e. biofuel production), and I participated to the development of a biophysical method to study metalloprotein properties (Far-IR spectroscopic). Since my recruitment (in 2020) as a CR CN by the CNRS, I focus on understanding how anaerobes manage to depolymerize the 2nd largest source of biopolymer on earth, the lignin from the plant biomass. Indeed, this abundant and cheap raw material represents an interesting but neglected reservoir of aromatic precursors that could be used by fine chemical industry to sustainably produce chemical commodities, a cheap and credible answer to our fossil ressource dependence.
Julien Herrou (Mignot lab - Laboratoire de Chimie Bactérienne, UMR 7283)
I have always been interested to understand how bacteria adapt and survive to changing environments and how microorganisms perceive and integrate environmental signals. Since my recruitment (in 2019) by the CNRS, I study the predation process of the model organism, Myxococcus xanthus. M. xanthus is a motile bacterium commonly found in the soil where it can hunt and kill other microorganisms to feed and grow. When M. xanthus encounters a prey, it stops moving and the prey is lysed in a contact-dependent manner. Using different approaches (microscopy, protein biochemistry and molecular biology), I am working on deciphering the signal transduction pathway that controls motility and prey intoxication when a prey is perceived.
Sybille Tachon (Magalon lab - Laboratoire de Chimie Bactérienne, UMR 7283)
I am a teacher and researcher in Microbiology since September 2020 and I am particularly interested in the study of gut and food associated bacteria. During my PhD at INRA and my two postdocs at the University of California in Davis and Aix-Marseille University, I worked with many different microorganisms (Salmonella, Clostridium, Bacteroides or Lactobacillus and many more !) on different projects (ranging from the study of the capacity of bacteria to lower environmental oxydo-reduction potentials to the impact of food matrix on the gut microbiota). Thanks to this rich research experience, I have a strong expertise in the development of global and molecular approaches related to microbial ecology (involving high-throughput sequencing) and biochemistry of proteins and peptides. Recently, I have been particularly interested in bacterial phenotypic heterogeneity, a topic of growing importance in microbiology. Using different single cell analysis methods (cytometry, microfluidics and microscopy), I am currently working on understanding how this underestimated phenomenon drives bacterial adaptation in sudden environmental changes, notably in the gastrointestinal track where ingested bacteria can experience very harsh conditions.
Matthieu Berge (Latifi lab - Laboratoire de Chimie Bactérienne, UMR 7283)
During my PhD in the Claverys Lab (2012 - University of Toulouse), I studied Streptococcus pneumoniae's natural genetic transformation and its integration and coordination with cell division. Then, I did my post-doc in the Viollier lab (2013-2020, University of Geneva) to work on the cellular differentiation of Caulobacter crescentus. I discovered new polar and enzymatic factors that play a fundamental role in triggering and orchestrating cell differentiation. In 2020, I was recruited as a CR CN by the CNRS. My current project is to understand how the circadian rhythm controls the multicellular differentiation of the cyanobacteria Nostoc PCC7120. Thanks to the different expertise I acquired over the years (notably in microbial genetic and cell biology), I will use multiple approaches (ranging form fluorescence microscopy to high-throughput sequencing) to study gene regulation, bacterial adaptation and cell differentiation during the circadian cycle. More specifically, I am trying to develop a long-term time-lapse fluorescence microscopy assay to follow, over several days and at the single cell level, each step of Nostoc developmental program during the circadian cycle.
Simon Duval (Schoepp-Cothenet lab - Bioénergétique et Ingénierie des Protéines, UMR 7281)
I am researcher in a team interested in the evolution and emergence of life. I started working on bioenergetic chains to understand the building blocks of bioenergetics. During my PhD, this led me to work on metabolism using particular substrates such as arsenic. During my different postdocs, I became interested in the mechanism of different metaloenzymes involved in bioenergetics (e.g. Nitrogenase when I was in USU lab in Utah). In 2018, I was recruited as CR CN by the CNRS to understand the mechanisms involved in the emergence of life with the idea that mechanisms that are present in all bioenergetic systems were similar before the origin of life. Based on this hypothesis, we observed that many bioenergetic metallo-enzymes were present in the so-called LUCA (Last Universal Common Ancestor), the oldest cell entity accessible to phylogenetic approaches. The active sites of many of these ancient metallo-proteins show strong similarities to the metallic structures of some minerals thought to have been present ~ 4 billion years ago. My project is to elucidate the prebiotic catalytic reactions involved in primitive metabolism by an innovative approach combining biology (phylogeny, enzymology), biophysics-chemistry, and geology.
Magali Roger (Giudici-Orticoni lab - Bioénergétique et Ingénierie des Protéines, UMR 7281)
I am interested in bacterial metabolisms, in particular how bacteria can adapt to multiple substrates to sustain growth in changing environments. During my PhD, I focused on the characterization of the molecular players (metalloenzyme) of bacterial metabolism using biochemical, biophysical and structural approaches. During my first postdoc (Sargent Lab, UK), I have been interested into the hydrogen (H2) metabolism of Escherichia coli. My objective was to rewire E. coli for carbon dioxide (CO2) fixation using H2 as energy source, which is not expected by bacteria in Nature. Using synthetic biology combined with chemical engineering, I designed an efficient laboratory-scale bioprocess for the conversion of CO2 into valuable chemicals. Keeping with this research continuum, I joined the BIP laboratory (Giudici Lab) for a second postdoc which aimed at deciphering the metabolic interactions network between two bacteria involved in the process of microbial bio-H2 production using cell biology and quantitative proteomic approaches. Following my recruitment in 2022, I am now trying to unveil the molecular basis of bacterial cooperation by developing new ecological models. In particular, I am currently interested in the role of quorum sensing in triggering bacterial interactions and its link with the metabolic activity of microbial communities.