Overview

Since the emergence of Synthetic Biology, bacteria have been engineered to perform a wide variety of simple tasks. They can be made to express proteins, respond to their environment and communicate primitively with each other. Presently, a key goal for the field is to create a communicating, organised and differentiated population of bacteria that can be considered a multicellular organism, capable of performing even more complex tasks. To realize this goal requires the development of systems for rapid, robust communication and self-organised differentiation. Our project sets the foundation for future research in engineered multi-cellularity by pursuing electrical and peptide signalling, and cellular self-differentiation through spontaneous spatial patterning.

Voltage

In order to simulate neural activity in bacteria, a mechanism resembling a synapse is necessary. This is the aim of the Voltage section of the Cambridge iBRAIN project. At the synapse, neurotransmitter molecules are released from the presynaptic plasma membrane. The neurotransmitter diffuses through the synaptic cleft and binds to chemical receptor molecules on the membrane of the postsynaptic cell. These receptors cause ion channels to open so that ions rush out, changing the transmembrane potential. Attempting to mimic this in a prokaryotic system is particularly attractive as, in a more general sense, it provides an interface between chemical or biological and electrical systems.

Signalling

Bacillus

Building on the work of the last year's Cambridge iGEM team, we are exploring applications of the gram-positive chassis ''B.subtillis''. Easy to handle and transform, this bacterium is much better to use than ''E.coli'' wherever protein import/export is concerned, e.g. in our signalling project. An important part of our effort is to establish standard protocols and parts to work in ''B.subtillis'', characterise control elements, and develop new vectors. As a part of this work we have utilized single copy chromosomal insertion, InFusion assembly, and an improved GFP variant.

Modelling