Foresight Among E. coli

Science Signaling  10 Jun 2008:
Vol. 1, Issue 23, pp. ec217
DOI: 10.1126/scisignal.123ec217

Many natural signals progress in a readily predictable sequence. For instance, after being eaten, a bacterium will perceive a sudden temperature rise followed by a drop in oxygen levels. Tagkopoulos et al. (see the Perspective by Baliga) investigated Escherichia coli’s predictive powers in a combination of in silico and chemostat experiments. On exposure to a large temperature change, E. coli can shift from aerobiosis to anaerobiosis even in the presence of 18% oxygen. This might seem maladaptive, but it means that the organism will have a competitive edge as soon as it encounters the zoo of microorganisms in the oxygen-starved lower gut. Furthermore, the authors were able to "train" the organisms to adapt metabolically to "unnatural" sequences of events, e.g., elevated temperature followed by high oxygen.

I. Tagkopoulos, Y.-C. Liu, S. Tavazoie, Predictive behavior within microbial genetic networks. Science 320, 1313-1317 (2008). [Abstract] [Full Text]

N. S. Baliga, The scale of prediction. Science 320, 1297-1298 (2008). [Summary] [Full Text]