SYSTEM TEMPLATE DESIGNS. “Modules may also be related by shared design or functional principles, even if they are not related by descent. The pheromone-detection system of budding yeast and the chemotactic machinery of bacteria use unrelated components, but both pathways achieve a sensitive response over a wide range of pheromone or chemoattractant concentrations by using reactions that specifically turn off active forms of the signalling receptors.”
https://www.nature.com/articles/35011540