Bacteria breakthrough is heaven scent

August 15, 2010, Newcastle University

Bacteria are well-known to be the cause of some of the most repugnant smells on earth, but now scientists have revealed this lowest of life forms actually has a sense of smell of its own.

A team of marine microbiologists at Newcastle University have discovered for the first time that bacteria have a molecular "nose" that is able to detect airborne, smell-producing chemicals such as .

Published today in Biotechnology Journal, their study shows how bacteria are capable of 'olfaction' - sensing volatile chemicals in the air such as ammonia produced by rival bacteria present in the environment.

Led by Dr Reindert Nijland, the research also shows that bacteria respond to this smell by producing a - or 'slime' - the individual bacteria joining together to colonise an area in a bid to push out any potential competitor.

Biofilm is a major cause of infection on medical implants such as , artificial hips and even breast implants. Also known as 'biofouling' it costs the marine industry millions every year, slowing ships down and wasting precious fuel. But it also has its advantages. Certain biofilms thrive on petroleum oil and can be used to clean up an oil spill.

Dr Nijland, who carried out the work at Newcastle University's Dove Marine Laboratory, said the findings would help to further our understanding of how biofilms are formed and how we might be able to manipulate them to our advantage.

"This is the first evidence of a bacterial 'nose' capable of detecting potential competitors," he said.

"Slime is important in medical and industrial settings and the fact that the cells formed slime on exposure to ammonia has important implications for understanding how biofilms are formed and how we might be able to use this to our advantage.

"The next step will be to identify the nose or sensor that actually does the smelling."

This latest discovery shows that bacteria are capable of at least four of the five senses; a responsiveness to light - sight - contact-dependent gene expression - touch - and a response to chemicals and toxins in their environment either through direct contact - taste - or through the air - smell.

Ammonia is one of the simplest sources of nitrogen - a key nutrient for bacterial growth. Using rival bacteria Bacillus subtilis and B.licheniformus, both commonly found in the soil, the team found that each produced a biofilm in response to airborne ammonia and that the response decreased as the distance between the two bacterial colonies increased.

Project supervisor Professor Grant Burgess, director of the Dove Marine Laboratory, said that understanding the triggers that prompt this sort of response had huge potential.

"The sense of smell has been observed in many creatures, even yeasts and slime moulds, but our work shows for the first time that a sense of smell even exists in lowly bacteria.

"From an evolutionary perspective, we believe this may be the first example of how living creatures first learned to smell other living creatures.

"It is an early observation and much work is still to be done but, nevertheless, this is an important breakthrough which also shows how complex are and how they use a growing number of ways to communicate with each other.

"Bacterial infections kill millions of people every year and discovering how your bacterial enemies communicate with each other is an important step in winning this war. This research provides clues to so far unknown ways of bacterial communication."

Explore further: Highlight: Bacterial biofilms make the seeds of their own undoing

More information: 'Bacterial Olfaction ' by Reindert Nijland and Grant Burgess. Biotechnology Journal, September 2010. Available online : 16 August, 2010. DOI: 10.1002/biot.201000174

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Aug 16, 2010
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not rated yet Aug 16, 2010
Using this 'nose' sounds like slavery to me but hey we are already at war with many of them and they are also fighting each other.
(just kidding)
5 / 5 (3) Aug 16, 2010
Getting emotional about it and throwing insults of believing in a fairytale just doesn't change the fact - we don't know. [By the way believing in Darwinian evolution is a fairytale].

I've heard evolution been called several things, but a fairytale? Get real.
5 / 5 (4) Aug 16, 2010
Notice how this sentence has nothing to do with the actual operational science of figuring out that bacteria responds to the presence of ammonia.
This is simply this man/team's speculation that bacteria therefore was a precursor to mammals or other higher order organisms which possess the sense of smell.
It isn't speculation, it is the highest probability.
An equally valid statement could be that the bacteria and mammals were created just the way they are in the first place.
Except there's no evidence.
And no-one could disprove that statement in any manner of form - because no-one was there to document it and bring us the history of how bacteria developed in the past.
Well this is entirely false logic.
Getting emotional about it and throwing insults of believing in a fairytale just doesn't change the fact - we don't know.
The only person getting emotional here is you. The only person hurling insults is, again, you. You need an education.
not rated yet Aug 16, 2010
Why are smell, taste and touch considered different senses, in so far as bacteria are concerned?
contact-dependent gene expression - touch

Sounds an awful lot like the slime-producing smelling going on here. Rather anthropomorphic of us to call something we do with our nose smelling when it is all based on molecular contact to a bacteria. Semantics. I guess if the touch response were pressure driven rather than specific to the composition of the toucher I could concede that point at least. But taste and smell? We need to get over ourselves.
5 / 5 (1) Aug 17, 2010
Why are smell, taste and touch considered different senses, in so far as bacteria are concerned?

Smell and taste ARE the same sense we human just process the data differently. Bacteria are just detecting chemicals in their environment. Touch is different. It is detecting physical contact.

Rather anthropomorphic of us to call something we do with our nose smelling when it is all based on molecular contact to a bacteria.

Touch is based on detecting pressure. In the article they differentiate between smell and taste by the way the chemicals that are being detected are carried, either by air or liquid. Which is something bacteria likely do not differentiate. So on that I think you have a point.

It may not be a matter of 'getting over ourselves', sometimes it is difficult to avoid anthropomorphic writing because, well, language is inherently anthropomorphic.

5 / 5 (2) Aug 17, 2010

Where is some evidence to support you?

I think SH covered your post pretty well so I will leave it at that. Just that question you won't answer. And this one.

If you have no evidence why do you believe things that are clearly shown false by pretty much the entire Universe.

1 / 5 (4) Aug 17, 2010
The problem of this experiment is, ammonia helps bacteria to survive better the acidification of environment, which is product of their own metabolism, i.e. there is no conclusive evidence of chemotaxis.
1 / 5 (4) Aug 17, 2010
The arrangement of experiment actually excludes the chemotaxis.

5 / 5 (1) Aug 19, 2010
I think we can ignore pretty much anything Kevin has to say because none of us was there to see him actually write it. Since we can't confirm the source we are free to ignore the information. Especially because it has so little to do with reality as we understand it.
4 / 5 (1) Aug 19, 2010
In fact, Kevin might do well to reexamine his own convictions because, by his own logic, he cannot trust the source of them as he was not there to see it being written. Nor was he present to witness the events it depicts.

In light of this fact it might be more logical to assume that his holy book was written not to show him the way to salvation but to convince gullible people like himself to ignore reality and reason in return for eternal life and the chance to suffer and die to attain it. Which obviously makes much more sense than what the book actually SAYS it is for.

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