Sensory Signalling in Rhodobacter Sphaeroides
Motile bacteria actively swim about their environment, randomly changing direction every few seconds. When faced with a gradient of a chemical they alter the frequency of direction changing to bias their overall direction towards a favourable environment. Bacteria are too small to sense any change in concentration across their body length, and therefore environmental sampling must occur by temporal comparison. A bacterium such as Rhodobacter sphaeroides, living under conditions where any one of many different growth parameters could be limiting, must be able to sense and respond to changes in different metabolites, light intensity and wavelength, oxygen and other terminal electron acceptors and balance these different sensory signals to give an integrated overall response.
KeywordsSwimming Behaviour Chemotactic Response Rhodobacter Sphaeroides Rhodospirillum Rubrum Bacterial Chemotaxis
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