Similar to computing on chips, the biochemical networks behind cellular computations are also constrained by energetic considerations, write Boston University's Pankaj Mehta and Princeton University's David Schwab in a paper posted online at arXiv. Mehta and Schwab examined a simple two-component cellular network "that encodes information about ligand concentration in the steady-state concentration of the activated form of a downstream protein" — which they note is common in bacteria — and calculated its energetic costs.