Zeiss Axiozoom V16 with the Apotome
Lars Kohler and John Cole
Zaida Luthey-Schulten Laboratory
Funded by the DOE, NIH, and NSF
This image offers experimental evidence for a theoretical model of how E. coli cells cooperate to use resources. The model predicted that oxygen becomes less available to cells inside the colony as it grows, and sugar is less available to cells at the top; cells near the base of the colony are expected to break down glucose into acetate, which would then be consumed by cells near the top. A dye used to label living colonies shows that cells near the surface do upregulate genes associated with acetate consumption, just as the model predicted.