Ricerc@Sapienza

From a Physics and Engineering standpoint, swimming bacteria are a formidable example of self-propelled micro-machines. Together with their synthetic counterpart, self-propelled colloids, they represent the "living" atoms of active matter, an exciting branch of contemporary soft matter and statistical mechanics. Differently from synthetic colloids, however, each bacterial cell contains all the molecular machinery that is required to self-replicate, sense the environment, process information and compute responses. Breaking down these biological functions into basic genetic parts has been one of the greatest triumphs of molecular biology. Today, synthetic biologists are assembling these parts into new genetic programs to exploit bacteria as computing micro-machines.
Project SYGMA will employ the synthetic biology toolkit to provide the building blocks for a light controllable active matter having reliable, reconfigurable and interactively tunable properties. Present active matter is mainly focused on controlling collective behavior by shaping the physical world outside active particles. SYGMA will move instead towards a completely different direction, where a deeper control on shape, structure and dynamics will be achieved by using light to remotely control the biological degrees of freedom inside each cell.
The project is articulated into three main work packages:
1. Light sensors for tunable dynamical response in single cells
We will use engineered photoreceptors to control speed, tumbling, growth and death rates
2. Biohybrid micro-machines with independent degrees of freedom
Teams of micro-shuttles propelled by bacteria will be guided independently by encoding motion directives into the spatial and colour structure of illumination light.
3. Optical control of population shape, structure and dynamics
By projecting a colour movie on a layer of genetically engineered bacteria we will control the shape, structure and dynamics of swimming and colony forming bacteria.