Experts have found that bacteria can "see" in much the same way as humans, by using their bodies as tiny lenses.
Research has shown that each cell acts as a microscopic eyeball or fibre optic filament.
The discovery solves a mystery that has baffled scientists for more than 300 years - how do bugs that rely on sunshine to survive sense light?
The answer is they do it by turning their whole body into a camera-like lens that focuses light onto a particular spot.
This triggers movement away from the focal point and towards the light source.
Lead researcher Professor Conrad Mullineaux, from Queen Mary University of London, said: "The idea that bacteria can see their world in basically the same way that we do is pretty exciting."
The team studied Synechocystis, a species of cyanobacteria - bugs that form the green slime on rocks and pebbles and which, like plants, photosynthesise to tap into energy from the sun.
An ability to sense light is crucial to the survival of these ancient microbes that evolved more than two billion years ago.
Previous studies have shown that they possess an ability to pinpoint the position of a light source and move towards it.
Now research shows that as light hits their spherical surface, it focuses onto a point on the other side of the cell. Within minutes, the bugs grow tiny tentacle-like structures called pili that reach out and pull the bacteria towards the light source.
Prof Mullineaux added: "Our observation that bacteria are optical objects is pretty obvious with hindsight, but we never thought of it until we saw it.
"And no-one else noticed it before either, despite the fact that scientists have been looking at bacteria under microscopes for the last 340 years."
A Synechocystis cell is about half a billion times smaller than the human eye.
0 nhận xét:
Đăng nhận xét