Choose a topic here:
Research interests
Combine theoretical and experimental approaches
Ecology and evolution
Organisms influence their environment through their activities, predation, nutrient excretion, habitat modification and populations evolve in response to changes in their environments. Such eco-evolutionary feedback loops might arise at different scale in space or time, at different levels of biological organization (genes, individuals, populations, community) and will be important in interacting populations.
The evolution of virulence
Human host could be an evolutionary dead end to many pathogenic bacteria. How can we explain the evolution of virulence? The coincidental evolution of virulence factors suggests that such virulence factors result from adaptation and might result from selective pressure exerted by predators. This hypothesis was tested experimentally (for more details see: From grazing resistance to pathogenesis: the coincidental evolution of virulence factors, Adiba S., Nizak C., van Baalen M., Denamur E., Depaulis F., PlosOne, 2010)
The emergence and evolution of collective behavior in microbes
Micro-organisms communicate and cooperate to form a wide-range of multicellular behaviors. The first step in this transition from unicellular to multicellular behavior is to form simple clusters through aggregation of cells. Aggregation of genetically distinct free-living cells could lead to conflict of interest among cells within clusters. How selection at one level affect selection at lower or higher levels?
A striking form of cooperation is found in the cellular slime mold or social amoeba Dictyostelium discoideum. When starving, single cells aggregate and form multicellular slugs that contain 10^4 to 10^6 cells. New features can emerge during the transition from unicellular to multicellular organism.
Compared to single cell,
slugs are able to migrate
toward the light
This dynamical process of the emergence of such collective function can be address with another organism: Pseudomonas fluorescens. When placed in a static microcosm, bacteria diversify via genetic mutation. The Wrinkly spreader mutant colonize the air-liquid interface and form biofilm (called "mat").
Natural selection and drift effect on polymorphism
Distinguishing random genetic drift from natural selection is still challenging and the most general question concerns the relative evolutionary importance of random genetic drift versus natural selection. We combined evolutionary experiments and theoretical model based on the classic Wright-Fisher model.
Skills
Microbiology, microscopy (phase contrast, fluorescence, time lapse), flow cytometer
Statisctics (with R software) and modelling.
PhD thesis
Natural selection and genetic drift effects on neutral polymorphism.
Advisors: Minus van Baalen (CR1 CNRS ENS) and Frantz Depaulis (CR1 CNRS ENS)
Successfully defended on Decembre, 13, 2010 (ENS)
Teaching
2015: M2 ENS Ecology and evolution (experiments) (20H)
2010: L3 ENS Theoretical model and experimentation in evolution (4h)
Reviewing
2014: Plos One
2011: African Journal of Biotechnology
Collaborators
Silvia De Monte (CR1 CNRS ENS)
Frantz Depaulis (CR1 CNRS ENS)
Minus van Baalen (CR1 CNRS ENS)
Pr. Erick Denamur (Bichat Medical School)
Clément Nizak (CR1 CNRS, ESPCI)
Students
Orso Romano (PhD ENS, Silvia De Monte, CR1 CNRS ENS; Chris Bowler;
collaborator: Paul Rainey(NZIAS, New Zealand ))
Félix Geoffroy (M2 AgroPariTech, 2015, Silvia De Monte, CR1 CNRS ENS; Clément Nizak, CR1 CNRS ESPCI)
Jacub Voznica (L3 ENS Cachan, 2015, Silvia De Monte, CR1 CNRS ENS)
Mounira Smati (PhD, 2011-2014, Pr. Erick Denamur, Bichat Medical School)
Anne-Sophie Daubié (M2 2014, Pr. Erick Denamur, Bichat Medical School)
Christophe Bénédet (M2, 2010)
Aksha Middya (M1 ENS ,2010)
Dominique Carval (PhD ENS, 2005-2009,Pr. Régis Ferrière, ENS)
Communications and publications
- The role of the high pathogenicity island in the virulence of the Escherichia coli species is depending on the genetic background of the strain and of the functional class of the gene. Smati M., Adiba S., Schubert S., Wieser A., Magistro G., Picard B., Denamur E. in prep.
- Abiotic and biotic factors effects on temporal allele frequency variations. Adiba S., Elard L., Depaulis F. in prep.
- Natural selection and genetic drift effects on neutral polymorphism, Adiba S., Lambert Edition, 2011
- From grazing resistance to pathogenesis: the coincidental evolution of virulence factors, Adiba S., Nizak C., van Baalen M., Denamur E., Depaulis F., PlosOne, 2010
- Experimental evolution of local parasite maladaptation, Adiba S., Huet M., Kaltz O., JEB, 2010
- Selection and drift in interacting polymorphic populations, Adiba S., van Baalen M., Depaulis F., 2008, Poster
- Experimental evolution of local adaptation in a microbial host-parasite system, Adiba S., Huet M., Kaltz O. Roscoff , 2007, Poster