A recently published study by researchers at the University of Hawai’i (UH) at Mānoa revealed that bacteria change their swimming patterns when entering tight spaces, rushing to escape confinement.

Almost all organisms harbor bacteria that live in symbiosis on or within their bodies. Hawaiian bobtail squid, Scolopes of Euprymnaforms an exclusive symbiotic relationship with marine bacteria Vibrio fischeriwhich has a whip-like tail which it uses to swim to specific locations on the squid’s body.

A research team, led by Jonathan Lynch, who was a postdoctoral fellow at the Pacific Biosciences Research Center (PBRC) at UH Mānoa School of Ocean and Earth Science and Technology (SOEST), designed controlled chambers in which they could observe the V.fischeri swimming bacteria. Using microscopy, the team found that when bacteria move between open areas and tight spaces, they swim differently. Specifically, they modify their swimming behavior to avoid getting stuck in confined spaces.

“This discovery was quite surprising,” said Lynch, who is now a postdoctoral fellow at the University of California, Los Angeles. “At first, we were looking to find out how bacterial cells change the shape of their tails as they move through tight spaces, but we found that we had trouble finding cells in the tight spaces. closer, we figured out it was because the bacteria were actively swimming out of the tight spaces, which we didn’t expect.

In the open spaces, with no chemicals to attract or repel, the bacteria seemed to meander without any discernible pattern, changing direction randomly and at different points in time. As soon as they entered confined spaces, the bacteria straightened their swimming trajectories to escape confinement.

The relationship between squid and this bacterium is a useful model of how bacteria live with other animals, like the human microbiome. Microbes often traverse complicated pathways, sometimes squeezing through tight spaces in tissues, before colonizing their host organism’s preferred sites. A variety of chemicals and nutrients in hosts are known to guide bacteria to their final destination. However, less is known about how physical features such as walls, corners, and tight spaces affect bacterial swimming, despite the fact that these physical features are found in many bacteria-animal relationships.

“Our results demonstrate that tight spaces can serve as an additional and crucial cue for bacteria as they navigate complex environments to enter specific habitats,” Lynch said. “Altering swimming patterns in tight spaces may allow some bacteria to quickly swim through tight spaces to get to the other side, but for others they flip before they get stuck, much like choosing cross a rickety bridge or turn around before you go too far.

In the future, researchers hope to understand how these bacteria alter their swimming activity, as well as determine if other bacteria exhibit the same behaviors.

– This press release was originally posted on the University of Hawaii at Manoa website