MicrobeWorld App

appsquarebannerad200x200

Join MicrobeWorld

Subscribe via Email

subscribe

Microbes After Hours

shutdown

Click for more "Microbes After Hours" videos

Featured Image

Featured Video

Crowdsourced Microbes Heading to Station

Supporters

ASM House 200X200

How Bacteria Talk to Each Other and Our Cells

Bacteria talk to each other using N-acylhomoserine lactones (AHLs) as quorum sensing (QS) signals. This signaling allows the bacteria to control gene expression of virulence factors and biofilms once a critical density has been achieved. This phenomenon, quorum sensing, is important when an infection propagates.

Now, researchers at Linköping University in Sweden are showing how bacteria control processes in human cells the same way, affecting cell migration in a dose- and time-dependent manner. When an infection is signaled, more and more bacteria gather at the site of the attack (a wound, for example). When there is a critical mass, the bacteria start acting like multicellular organisms. They form biofilms, dense structures with powers of resistance against both antibiotics and the body's immune defense system. At the same time, they become more aggressive and increase their mobility. All these changes are triggered when the communication molecules (short fatty acids, AHLs) bind to receptors inside the bacterial cells, triggering gene expression changes.

AHLs can migrate freely through the cell membrane, so that not just in bacterial cells but also in eukaryotic cells, cellular functional changes can be identified. In low concentrations, white blood cells can be more flexible and effective, but in high concentrations the opposite occurs, which weakens our immune defenses and opens the door for progressive infections and inflammations.
 
 

Comments (0)

Collections (0)

 

American Society for Microbiology
2012 1752 N Street, N.W. • Washington, DC 20036-2904 • (202) 737-3600

Copyright © American Center for Microbiology 2012. All Rights Reserved.