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Wireless Messaging for Bacteria
An Anonymous Coward writes: "According to BBC's article, UK scientists discovered that bacteria have a capability of warning each other over air about new antidotes introduced and by doing so help to develop a resistance to antibiotics! Speaking of 802.11 standard amongst microbes! This is so twisted!"
Hmmm. Altho the article is not detailed enough to really tell whats going on, there are other possibilities besides communication, chemical or otherwise, between the bacteria. What they have is a SYSTEM consisting not only of bacteria, but also moist growth medium, antibiotics, air, and the plastic or glass petri dish. Let's say the plastic/glass is inert and isn't playing a role in the effect. Possible there is some interaction between just the air, moist growth medium and antibiotic and the EFFECT of this interaction is happy bacteria, which aren't participating in originating the effect. For example, putting in the 5 mm gap in the wall to connect the two chambers also allows water vapor transfer between the dosed and undosed media. If the bacteria colonies grow and absorb water, the media around them becomes dryer and the drug more concentrated and deadly. If there's a vapor pathway to fresh medium, maybe the dry drugged medium absorbs water thru the air from the undrugged fresh medium, diluting it. Since the bacteria are only growing on the surface, this is enough to keep them going. I'm not saying this is what IS happening, I'm saying that true science is about trying to consider ALL possibilities, even the ones that won't make the news, like water vapor transfer instead of bacterial chemical warning signals. Rule one in science is always consider some other (usually unglamorous) possibility.....
A more interesting story title would have been "Wired Messaging for Bacteria". As far as I know, no bacterial colony has been caught setting up and using a wired telecommunications network. (The pond-scum at Qwest have gotten close, but they're certainly not there yet.)
1. For the airborne "messages" to be sent, I'm assuming that the E.coli cultures were in open air, and not in water. So each side of the divider was pretty much in the same system.
They were in a petri dish which had a dividing wall cutting it into two sections. There was a 5 mm gap between the dividing wall and the roof, so they weren't exactly in "open air"
2. If "pheremones" were able to cross through the gap, then the antibiotics should have been able to also.
To the best of my knowledge, antibiotics can't migrate through the air (there may be a few varities which can, but the vast majority can't), so they shouldn't migrate across the barrier.
If you have an ammount of antibiotics x, and another number of E.coli y, then you will have the ratio of antibiotits to bacterium x/y. If x is a large number compared to y, then the E.coli have small chance of survival... more "poision" per cell. But if you were increase y, then the ammount of "poision" per cell decreases in the system, thus improving the chance for each individual cell to survive.
This isn't exactly how the bacteria survive. Generally only a small amount of antibiotics is needed to kill a bacteria infection. However a tiny minority of bacteria (maybe one in a billion) will mutate (or already possess the mutation) so it is immune to the antibiotics. These bacteria will either repopulate the petri dish with their clones, or pass on the mutation to other non-clones (bacteria commonly swap genetic material) allowing them to survive. Therefore it isn't a simple x/y ratio.
Warning: Some ideologies on the Net are smaller than they appear.
If they had anything why wouldn't they publish their results in Nature?
"We've tried without success to isolate the chemical signal from the air by dissolving it. Next we'll try gas chromatography."
They havn't even isolated it! Gah. Sending your results to New Scientist is about as professional as posting them on Slashdot.
How we know is more important than what we know.
The mechanism already known to do this is quorum-sensing. Researchers didn't know any airborne agents used in such a process.. They're talking about thriving populations; one of the main purposes of quorum sensing in the regulation of population growth. If cells are thriving, it means they 'know' due to quorum sensing there is enough food and room to duplicate.. Let's say those microbes in the dish with antibiotics gets a 'duplicate'-signal, the effect could be stronger than the presence of antibiotics. Microbes can reduce the stress induced by antibiotics actively. In the end, they'll die unless they're resistant. So if the 'multiply'-signal could induce multiplication instead of fighting the stress without a sufficient effect, the microbes in the antibiotic solution could just outrun the extinction effect by duplicating faster. Could be a new airborne 'divide'-signal. Resistance-signals are VERY unlikely!
You do not exist. Go away.
... but as someone who now works in biotech, I suppose this sort of thing represents job security ...
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.