Engineering Scalable Digital Circuits From Non-digital Genetic Components

Synthetically engineered single-cellular biological systems could be designed to classify patterns of chemical signals with high specificity and invoke appropriate responses. This requires cells to produce accurate logical computation over their multiple inputs and then trigger cellular response in a binary form like the signals YES and NO. However, current engineered biological systems, as a rule, are built from components like combinatorial promoters that, although displaying ’logic like’ capabilities, fall short of supporting true binary (Boolean) computation. Consequently misclassification of inputs or errors in processing commonly occur that in turn lead to an incorrect cellular response. Here we show how that increased nonlinearity combined with noise suppression leads to genetic circuits capable of true Boolean logic operation able to support scalable logic circuit design.