Overview

Why E.calculus ?

Within our brainstorming meeting to define our iGEM project, we realized that various arithmetic operations were present in many cellular systems, like intracellular regulations and controls, or even in control of metabolic pathways. We therefore decided to create a n-bit bacterial full adder, which could be adjustable by the user, and able to transmit a carry if needed. Considering some of the previous iGEM projects already based on the adder concept, and using new systems of logic recombinatorial gates, we aim to create a robust and strong device able to be implemented on bacterial chassis. We also want to demonstrate in this project how recombinatorial gates could be considered as the easiest and strongest way to build genetic logic gates, which could be used together in the creation of many genetic devices.

From TI83+ to E.calculus

An electronic full-adder consists of the association of 5 logic gates (2 XOR gates, 2 AND gates, and 1 OR gate) which are able to account for 3 input signals (2 input bits and the last stage carry) and give the right answer to the user. (View "Full Adder" Part)

With E.calculus, we also try to transpose this electronic device into a genetic device (system) based on recombination principle. We chose to use blue and red light as bit inputs (View "Input" Part), and a diffusive molecule for the carry (View "Carry" Part) . The answer should be readable by the manipulators, that is why we chose to use a red pigment (View "Output" Part), visible by human eyes at a low concentration.