Medical Research Council - London Institute of Medical Sciences

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Bacterial swimming controlled by light – potential for developing drug-carrying devices

12 February 2019

Swimming Strokes

Bacteria swim around inside our guts using tiny propellers, called flagella, fuelled by chemicals sluicing nearby. Here Escherichia coli (E.coli) bacteria are using a different energy source – proteorhodopsin – which releases energy when exposed to light. Under an illuminated pattern, the bacteria swim quickly in lit areas, and slowly in unlit ones, producing – with a little guidance from clever physics – a portrait of Albert Einstein matching a projected image. Switching the pattern signals the bacteria to paint a different picture – guided by changes in the light and dark areas. Einstein’s face morphs into Charles Darwin, a living portrait created in around five minutes. Aside from giving the tiny swimmers a new hobby, scientists hope to use the artistic technique elsewhere – perhaps guiding clouds of bacteria to push drug-carrying devices around the body. It’s likely both Einstein and Darwin would approve.

Today is the 210th Anniversary of Charles Darwin's birth

Written by John Ankers

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