Synthetic Biology: A Systems Engineering Perspective

In this work, we provide a review from a systems engineering perspective of some of the design challenges found in bio-molecular systems. In particular, we focus on the problem of modularity. If components behave modularity, that is, their behavior does not change upon interconnection, then one can predict the behavior of a circuit directly by the behavior of the composing units. We show how this can be performed in two instances of oscillating synthetic bio-molecular systems. Then, we illustrate that modularity does not necessarily hold in bio-molecular systems because of impedance-like effects, called retroactivity, at interconnections. We propose a framework for quantifying retroactivity at interconnections between transcriptional circuits and illustrate a mechanism, inspired by the design of electronic non-inverting amplifiers, to counteract retroactivity1 .