Domaines
Statistical physics
Biophysics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Bacterial colonies on agar are usually studied from above, with the gel treated as a
passive support and a nutrient reservoir. Yet a colony is a strong sink and source of
water: cells take up water to grow, secrete osmolytes and surfactants that pull water
out of the gel, and spread within a thin liquid film they produce themselves. Agar,
which is about 98% water, is a porous medium, so this water has to come from
somewhere. As the colony expands, water is drawn through the gel network toward
the colony, the gel shrinks, and gradients of water content build up beneath and
ahead of the colony front. These flows are almost never measured. Yet, they may still
control colony expansion and the shape of the colony edge.
Contact
Maxime Deforet