E. coli do the wave

Now someone just has to engineer them to shout WOOOOOOOOAAAAH!



Being able to predict recurring phenomena in the environment in order to adapt to them better offers an immense advantage to an organism. That's why pretty much all living things have an internal molecular clock that quite literally "ticks", it oscillates back and forth and allows the organism to tell what time it is. This probably arose in unicellular organisms to protect the delicate DNA molecule from the danger of UV light from the sun by timing DNA replication, when the molecule is exposed, to the nighttime hours. Having an internal clock would also allow this unicellular organism to separate different chemical reactions in time to prevent them from interacting with each other. Us multicellular organisms not only coordinate our cellular chemical reactions by time, we also adapt our behavior and our physiology. Sleep is the most dramatic example, but the release of most hormones for instance varies during the 24-hour cycle and it's also worth mentioning the many seasonal migrations that criss-cross the globe every year. In essence, time keeping is an elementary part of being alive.

The authors of the paper described in the video above have managed to connect this time keeping mechanism in E. coli with a mechanism that the bacteria use to communicate with other cells in the colony, called quorum sensing, thus making the whole colony oscillate in near synchrony. This is visualized by adding the gene for green fluorescent protein into the molecular clock, something the authors reported already in 2008. The result, as you can see in the video, is a propagating wave of flashing bacteria.

This is not only a beautiful demonstration of a fundamental function of all living cells, it's an elegant use of the available biotechnology and it advances the repertoire of molecular tools we have at our disposition for the creation of useful organisms in the future.

Danino, T., Mondragón-Palomino, O., Tsimring, L., & Hasty, J. (2010). A synchronized quorum of genetic clocks Nature, 463 (7279), 326-330 DOI: 10.1038/nature08753

Swedish blog tags: Vetenskap, Biologi, Bioteknologi
Technorati tags: Science, Biology, Biotechnology, Chronobiology, E. coli