17. 10. 13
This interesting social bacterium shows fascinating behaviors which have crowned it as a model organism in Systems Biology. One of the most recent discoveries has to do with its ability to "create waves"
A research group of the University of Texas has observed how the individual movements of each bacterium are amplified within the bacterial swarm, forming powerful waves that push it forward in unison. The waves formation phenomenon appears to be associated with the existence of prey bacteria, i.e., if there is food at the edge of the colony, the waves are much stronger. The results have been published in PLOS Computational Biology
Imagine a cell at the edge of the colony. If it moves forward, you probably will not find any other cell of M. xanthus, thus the cell does not receive any chemical signal and that prevents it from proceeding. But if it moves backwards, it will most certainly collide with an M. xanthus companion, so it receives a stimulus, making it spin and continuing in the opposite direction. Therefore, the net result is that the swarm moves constantly at their edge.
Furthermore, this can give rise to the swarm self-organising itself in waves of alternating density, displaying a behavior of collective oscillating mobility. It is not a typical reaction-diffusion system, since waves of opposite direction do not annihilate each other, instead they move through each other.
To verify that the model predictions worked, the research group next observed the formation of waves in the presence of a prey bacterium under a microscope (our old friend Escherichia coli). In this manner, they confirmed the relationship between the wavelength of the waves, the refractory period and cell movement speed. The molecular mechanism of this 'touch' is still unknown, but it is quite interesting because it would allow the design some kind of contact swith to regulate functions in nanotechnology mechanisms or in organisms designed by synthetic biology.
Zhang H, Vaksman Z, Litwin DB, Shi P, Kaplan HB, & Igoshin OA (2012). The Mechanistic Basis of Myxococcus xanthus Rippling Behavior and Its Physiological Role during Predation. PLoS computational biology, 8 (9) PMID: 23028301
The Dubai International Convention & Exhibition Centre will host the largest health fair and conference in the Middle East. Laboratorios CONDA will be present from 25 to 28 January,...
As every year, Laboratorios CONDA will participate in the medical industry’s main trade fair. From 16 to 19 November, we will be delighted to see you at Medica, catch up, and evaluate the...