JUN 24, 2016 11:27 AM PDT

Plant pathogen uses enzymes to escape sticky traps

WRITTEN BY: Kerry Evans
I don’t think a lot about plant pathogens, but I probably should. They can have a profound effect on our food supply, for example.

The plant pathogen Ralstonia solanacearum colonizes the xylem of plants, impeding fluid flow and causing a disease called wilt. This pathogen affects many types of commercially-important plants, including potatoes, tomatoes, soybeans, and even bananas.
Bacterial wilt caused by R. solanacearum.
R. solanacearum are aerobic, Gram-negative bacteria that live in the soil. They are also motile, using their polar flagella to travel between unsuspecting plant roots.

Recently, researchers at the University of Wisconsin, Madison, described how this particular pathogen escapes from plant extracellular traps.

If you think “plant extracellular traps” sounds sounds eerily similar to “neutrophil extracellular traps”, you’d be right. Animal cells often produce so-called NETs that trap invading pathogenic bacteria. As always, these bacteria have a way to fight back - they produce DNases that degrade the NETs.

Turns out, the same is true of plant pathogens. The UW Madison group found that R. solanacearum secretes two DNases that help the bacteria escape extracellular traps. These traps are produced by plant border cells after they come into contact with the bacteria. In the case of R. solanacearum, the presence of bacterial flagellin induces the plant cells to secrete the traps.

The researchers knew that R. solanacearum produced two putative extracellular DNases, NucA and NucB. They decided to test whether these nucleases helped R. solanacearum escape from the plant extracellular traps.

Sure enough, bacteria lacking NucA and NucB were less virulent towards wilt-susceptible tomato plants.

Sources: PLOS Pathogens, Microbiology Bytes, Wikipedia
 
About the Author
  • Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
JUL 17, 2018
Videos
JUL 17, 2018
Novartis Ends Antibiotic Research
The United Nations has warned that by 2050, antibiotic-resistant microbes might kill ten million people every year....
JUL 23, 2018
Microbiology
JUL 23, 2018
Anglerfish Alert Researchers to a Third Type of Symbiosis
The light from inside the anglerfish bulb is made by bioluminescent bacteria, a symbiotic relationship we know little about....
JUL 27, 2018
Microbiology
JUL 27, 2018
Making Accurate Assessments of the Environmental Impact of Pollution
Without the right experimental design, behavioral testing can easily produce the wrong results....
SEP 18, 2018
Microbiology
SEP 18, 2018
The Earliest Influences on the Microbiome Have a Lasting Impact
We coexist with microorganisms, and many of them play an important role in our health....
SEP 27, 2018
Microbiology
SEP 27, 2018
How Bacterial Cells Take out the Trash
Some types of bacteria create tiny versions of themselves that cannot reproduce - miniature spheres lacking chromosomal DNA that are known as minicells....
OCT 13, 2018
Microbiology
OCT 13, 2018
Gut Bacteria Connected to Heart Transplant Success - or Failure
The more they look, the more connections researchers find between our microbiome and our health....
Loading Comments...