Bacteria can tell time through internal clocksDate: 11 January 2021 Tags: Miscellaneous
New research has revealed that bacteria too have internal clocks that align with the 24-hour cycle of life on Earth.
The research answers a long-standing biological question and could have implications for the timing of drug delivery and biotechnology.
Biological clocks or circadian rhythms are exquisite internal timing mechanisms that are widespread across nature enabling living organisms to cope with the major changes that occur from day to night.
Existing inside cells, these molecular rhythms use external cues such as daylight and temperature to synchronise biological clocks to their environment.
Although bacteria represent 12% biomass of the planet and are important for health, ecology, and industrial biotechnology, little is known of their 24hr biological clocks.
Previous studies have shown that photosynthetic bacteria which require light to make energy have biological clocks. But free-living non photosynthetic bacteria have remained a mystery in this regard.
Researchers applied a technique called luciferase reporting, which involves adding an enzyme that produces bioluminescence that allows researchers to visualise how active a gene is inside an organism.
They focused on two genes: firstly, a gene called ytvA which encodes a blue light photoreceptor and secondly an enzyme called KinC that is involved in inducing formation of biofilms and spores in the bacterium.
They found that the pattern of ytvA levels were adjusted to the light and dark cycle, with levels increasing during the dark and decreasing in the light. A cycle was still observed in constant darkness.
Researchers observed how it took several days for a stable pattern to appear and that the pattern could be reversed if the conditions were inverted.
Significance of research
This research could be used to help address such questions as: is the time of day of bacterial exposure important for infection? Can industrial biotechnological processes be optimised by taking the time of day into account? And is the time of day of anti-bacterial treatment important?