Steady As She Blows

Models of metabolic regulation show how the stability of specific components is maintained within a varying environment. A fundamental characteristic of many biological control networksis the capacity to maintain the concentration of a particular component at steady state within a narrow range despite variations in the amounts of other network components that might change as a result of environmental variables in the state of a cell. In a mathematical analysis, Shinar and Feinberg reveal the essential requirements of a network robust to perturbation. Using this method, the sources of robustness in two bacterial systems—one that functions in osmoregulation and another that controls carbon flux in metabolism—were explained. G. Shinar, M. Feinberg, Structural sources of robustness in biochemical reaction networks. Science 327, 1389–1391 (2010). [Abstract] [Full Text]