A unique self-repair strategy found in bacteria is surprising scientists

In a new study, scientists from UNSW Sydney show how nature’s oldest wheel, found in bacteria, can fix itself when the going gets tough.

The results, published today in the journal Science Advances, show that flagella, an ancient motor that helps bacteria swim, can also help these tiny organisms adapt to situations where their ability to move is limited.

Bacteria are among the oldest species on Earth. Bacteria are tiny, single-celled organisms that can be found almost everywhere, including the human body, where they outnumber human cells.

The ability to move in water is essential for the survival and propagation of microbes. But not much is known about how the engines that propel them help them survive in dangerous places.

This is the first study to use CRISPR gene editing technology to modify the flagellar motor. They created a sodium-driven swimming bacterium by using synthetic biology techniques to build a sodium engine in the genome. Then they looked at how the bacteria changed when there wasn’t enough sodium in the environment.

Since sodium is an ion, it has an electrical charge. This charge powers the flagellar motor through ion channels or stators.

The results showed that the stators can quickly repair the flagellar motor and get the cell moving again. These results may lead to new discoveries in the fields of biology and medicine.

“We have shown that changes in the environment can cause ion channels to respond quickly,” said lead author Dr. Pietro Ridone notes.

“So the CRISPR edits also come back quickly and the flagellar motor develops and then regulates itself.”

“The fact that we immediately saw mutations in the stators is surprising and inspires our future research plans in this area.”

How powerful are molecular machines?

There are about 10,000 different types of molecular machines in the human body. These machines help the body do things like convert energy and move.

The bacterial motor is far more advanced than what humans can do at the nanoscale level. It is self-assembling and spins up to five times faster than a Formula 1 engine, one millionth the size of a grain of sand.

“The motor that powers bacterial swimming is a marvel of nanotechnology,” adds co-author and associate professor Matthew Baker. “This is an absolute poster child for ancient and very complex molecular mechanisms.”

According to the professor, the latest results could improve our mechanistic understanding of the history of molecular motors, including how they are put together and how they fit together.

“These ancient parts are a powerful system for studying general evolution, as well as the origin and evolution of mobility.”

Research, A/Prof. Baker will help scientists develop new molecular engines. The findings may also help to understand antibiotic resistance and disease pathogenesis.

“By shedding more light on life’s ancient history, we gain knowledge to create tools to help improve our future,” says A/Prof. Baker added, “it may also lead us to insights into how bacteria might adapt under future climate change scenarios.”

Source: 10.1126/sciadv.abq2492

Image credit: Getty