Making sense of it all: bacterial chemotaxis

Abstract

Bacteria must be able to respond to a changing environment, and one way to respond is to move. The transduction of sensory signals alters the concentration of small phosphorylated response regulators that bind to the rotary flagellar motor and cause switching. This simple pathway has provided a paradigm for sensory systems in general. However, the increasing number of sequenced bacterial genomes shows that although the central sensory mechanism seems to be common to all bacteria, there is added complexity in a wide range of species.

Bacterial chemoreceptors: high-performance signaling in networked arrays

“…The resulting interplay between motor control and sensory adaptation produces directed motile behavior. E. coli chemoreceptors are the most extensively studied representatives of the MCP super-family, central components of homologous systems that mediate tactic responses [5,6] across the phylogenetic diversity of bacteria and archaea [7].In E. coli chemotaxis proteins cluster in membrane-associated patches [8]. Interaction within patches is thought to contribute to notable features of the signaling system: high sensitivity, wide dynamic range, extensive cooperativity and precise adaptation.…”

Propulsion and Chemotaxis in Bacteria‐Driven Microswimmers

“…Thus far, the taxis‐based guiding method constitutes the major way to regulate the otherwise highly stochastic motion of bacteria‐driven microswimmers, which has been studied both in vitro17, 20, 21, 22, 23, 24, 25 and in vivo 14, 16. Chemotaxis, one of the most common taxis behaviors in bacteria, has been well understood36 and its signaling pathway has been mathematically modeled 37, 38, 39, 40, 41, 42, 43. In general, the chemotaxis of free‐swimming bacteria associates with a biased random walk, enabled by preferentially suppressed tumble tendency when the bacteria travel up a chemoattractant gradient; whereas in an uniform medium, the tumble tendency is isotropic over all swimming directions.…”

Spatiotemporal modelling of CheY complexes in Escherichia coli chemotaxis

“…This pathway has been most extensively studied in the Gram-negative rod-shaped bacterium, Escherichia coli (Wadhams and Armitage, 2004). Importantly, the localization (Maddock and Shapiro, 1993;Sourjik and Berg, 2000), copy number (Li and Hazelbauer, 2004) and reaction kinetics (www.pdn.cam.ac.uk/ groups/comp-cell/Rates.html) of most of the components of this pathway have been experimentally determined.…”