Achieving directional swimming by manipulating the diffusion constant
Chemotactic network enables most bacteria to achieve bias-random walk. The network transmits input signals from the environment to a rotary molecule motor. The output of the network is the frequency of directional changes of the motor rotation, which in the end controls the whole cell swimming trajectories.
Chemotactic network is sensitive and specific. However, it has also been shown to respond to signals that are bulk and non-specific in nature. To investigate if large concentration upshifts that can be found in the environments bacteria swim in lead to directional swimming, we look at individual motors under the environmental challenge. We find that the motors settle at a new steady state and discuss how the observed response translates into directed swimming of bacteria.