So we end up with a fresh cup of coffee from a clump of beans. It's like oil rigs extracting oil from dense rock formations under the seabed. It even helps to explain how forest fires spread.
A theory known as "percolation" now helps microbiologists at the University of California San Diego explain how communities of bacteria can effectively relay signals over long distances. Once considered a simple cluster of microorganisms. It has been discovered that bacterial communities – also called biofilms – use ion channels for electrochemical communication to help society survive and survive threats such as chemical attacks by antibiotics.
The results, led by Joseph Larkin and senior author Gürol Süel of UC San Diego, are published on July 25 in the journal Cell Systems
Biofilm communities inhabit places around around us, from the floor to the drainpipe, the surface of our teeth. Cells on the edge of these communities tend to grow more robustly than their inner counterparts because they have access to more nutrients. To keep this marginal growth in check and to ensure that the entire community is fit and balanced, the "hungry" members of the biofilm interior send electrochemical signals to the outside members. These signals stop eating at the border and allow nutrients to flow through the inner cells to prevent starvation.
"This keeps the interior adequately fed and if a chemical attack occurs and removes some of the outer cells, then the shelter is protected. The inner life can go on and the entire population can survive," said Larkin, a postdoctoral fellow at UC San Diego Biological Sciences. "It's important that the electrochemical signal is transmitted all the way to the biofilm rim, because that's where growth must be stopped so that the community can make the most of the signal transmission."
The researchers wanted to explain how bacterial communities can spread these electrochemical communication signals. Unlike neurons, which have named structures for the delivery of electrochemical signals known as axons, bacterial communities lack such sophisticated structures. This raised the question of how bacteria could transmit signals over long distances within the community so effectively.
After reviewing large amounts of bacterial data, researchers from UC San Diego began collaborating with Andrew Mugler and Xiaoling Zhai of Purdue University on the idea that percolation theory might explain how bacterial communities can spread signals from cell to cell.
The percolation theory has existed since the 1
In a community of bacteria, cell-to-cell signals connect over a distance of hundreds of cells. Using fluorescence microscopes, the researchers were able to "fire" individual cells (send a signal). The scientists found that the proportion of firing cells and their distribution in space coincided exactly with the theoretical predictions of the onset of percolation. In other words, the bacterial community had a fraction of firing cells at exactly the inflection point, between connectivity and complete connectivity between cells, also known as the critical phase transition point.
"We are all familiar with this – we make coffee by percolation and it is an interesting twist that bacteria apparently use the same concept to accomplish the very complicated task of efficiently passing an electrochemical signal over very long distances from cell to cell ", says Süel.
"Interesting These bacteria, called simple unicellular organisms, use a fairly sophisticated strategy to solve this problem at the community level," Larkin said. "It's sophisticated enough that we humans use it for oil extraction, for example."
Materials provided by University of California – San Diego . Original written by Mario Aguilera. Note: Content can be edited by style and length.