Figure 5
From: Cell-cell communication enhances bacterial chemotaxis toward external attractants
Chemotaxis competition between aspartate and the signaling molecule. (a) The signaling molecule is a stronger attractant than Asp. The chambers were filled with M9-G with 10 µM Asp prior to the loading of wt cells, followed by loading more than 5,000 cells into the microchambers. Fresh M9-G containing 200 μM Asp was pumped into the main channel when the cells start migrating toward the nook corner. The curves in different colors were obtained from three different chambers in the same experiment. The two inserted images are two snapshot from movie S4 at 10 min (left inset) and 85 min (right inset), respectively. It is likely that when cells accumulate at the nook corner they follow a cell-cell communication-generated signal and not the Asp gradient. (b) Serine is a stronger attractant than aspartate. The chambers were filled with M9CG before loading the cells. Fresh M9-G containing 300 µM Asp (blue symbol) was firstly pumped into the main channel after loading. The media in the main channel was then changed to M9-G containing 10 µM serine (red symbol). The two inserted images are two snapshot at 24 min (left inset) and 89 min (right inset), respectively.
