OCT 14, 2022 4:42 AM PDT

How Exactly do Bacteria Move? An Old Question is Finally Answered

WRITTEN BY: Carmen Leitch

Bacteria are single-celled organisms, and while we know they can move around with filaments, the exact mechanisms behind how they do so has been unclear for many years. Researchers have now used cryo-electron microscopy to reveal the structure of filaments on bacterial cells, and how they coil into corkscrews that are used to propel bacteria. These filamentous propellers are made of repeating subunits of only one protein. The findings have been reported in Cell.

Image credit: Pixabay

"While models have existed for 50 years for how these filaments might form such regular coiled shapes, we have now determined the structure of these filaments in atomic detail," said study leader Edward H. Egelman, Ph.D. of the University of Virginia School of Medicine.

This study has shown that the models that were developed are incorrect, said Egelman, but this new data "will help pave the way for technologies that could be based upon such miniature propellers."

Bacteria can have one or many flagella, which are made up of thousands of subunits, and although those subunits are all the same, they don't form an inflexible string, or a uniform structure. Instead, the subunits take on different states to create a rotating, propeller-like appendage that can be corkscrewed. The one protein that repeats many times to make up a flagellum is able to take on any one of eleven different states, and the combination of states enables the corkscrew to form. The compacted corkscrew generates thrusting power, which is then released to push the bacterium forward.

Bacteria can be seen moving in the video below.

Bacteria aren't the only single-celled organisms in town, however. Archaea are another type of single-celled organism that are known to carry flagella that can also behave like propellers.

The researchers assessed the flagella in one type of archaea, called Saccharolobus islandicus, in this study as well. They determined that the protein that forms the archaeal flagella has ten different states. So the details of the mechanism in archaea are different from bacteria, but the result is the same: the flagella form corkscrews that propel the cells.

The researchers noted that this is a type of convergent evolution, in which nature has arrived at the same place but taken different paths to get there. While bacteria and archaea carry flagella that enable movement, their traits evolved independently.

Sources: University of Virginia, Cell

About the Author
Bachelor's (BA/BS/Other)
Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
NOV 16, 2022
Coronavirus
Divergent SARS-CoV-2 Variant Reveals Evidence of Deer-to-Human Transmission
Divergent SARS-CoV-2 Variant Reveals Evidence of Deer-to-Human Transmission
After only a few months of the COVID-19 pandemic, researchers had identified the virus that causes the disease, SARS-CoV ...
NOV 28, 2022
Clinical & Molecular DX
Study Indicates that Breast Cancer Recurrence Could be Predicted Using a MicroRNA Biomarker
Study Indicates that Breast Cancer Recurrence Could be Predicted Using a MicroRNA Biomarker
MicroRNAs are small (between just 21 and 23 nucleotides), non-coding RNA molecules. They are involved in the post-transc ...
NOV 30, 2022
Drug Discovery & Development
Saying "Bye" to UTI E. Coli
Saying "Bye" to UTI E. Coli
In the arms race between animal and bacteria, endogenous antimicrobial peptides (AMPs) are our body’s way of defen ...
DEC 07, 2022
Immunology
A Mystery Solved - Why Colds & Flu Are More Common in Winter
A Mystery Solved - Why Colds & Flu Are More Common in Winter
Most people would agree that colds and especially flu infections are far more common in winter. While we know that some ...
JAN 11, 2023
Microbiology
Are Shopping Malls Superspreader Sites?
Are Shopping Malls Superspreader Sites?
A new study has shown that when people go to shopping malls, they take home more than new products, and they leave more ...
JAN 17, 2023
Microbiology
Viruses Destroy Crucial Immune Cells That Battle Fungal Infections
Viruses Destroy Crucial Immune Cells That Battle Fungal Infections
Fungi that can cause lung infections are all over our environment. Recent research has highlighted how much fungal speci ...
Loading Comments...