Researchers at the University of São Paulo (USP) in Brazil have described a system present in a species of opportunistic bacterium found in hospital environments that injects a cocktail of toxins into competing bacteria and completely eliminates them. This discovery can be used in the future development of new antimicrobial compounds.
The study was supported by São Paulo Research Foundation—FAPESP and published in PLOS Pathogens by researchers affiliated with USP's Chemistry Institute (IQ) and Biomedical Sciences Institute (ICB).
Researchers - Stenotrophomonas - Secretion - System - Cocktail
The researchers discovered that Stenotrophomonas maltophilia uses a secretion system that produces a cocktail of toxins and injects them into other microorganisms with which it competes for space and food. In addition, the researchers characterized one of 12 proteins in the cocktail—Smlt3024—and observed that this molecule alone can considerably reduce the rate at which other bacteria replicate.
"We believe these toxins can be explored as a form of treatment in the future. Just as antibiotics can come from other bacteria, we are exploring this arsenal used by bacteria themselves to kill other species of pathogen," said Ethel Bayer-Santos, a researcher at ICB-USP.
Study - Part - Project - IQ-USP - FAPESP
The study was part of her postdoctoral project at IQ-USP, which was also supported by FAPESP. She currently has a Young Investigator grant from FAPESP.
Bacterial secretion systems are protein complexes present on the cell membranes of bacteria for the secretion of substances. These systems are used by pathogenic bacteria to secrete virulence factors and invade host cells.
Type - IV - Secretion - System - T4SS
"The Type IV secretion system [T4SS], as it is known, secretes proteins and DNA into other cells or the extracellular medium. We recently showed that it is present in Xanthomonas citri, the pathogen that causes citrus canker. We have now found it in this bacterium [S. maltophilia], which is frequently isolated from water and soil but can become an opportunistic pathogen in hospital environments," said Shaker Chuck Farah,...
(Excerpt) Read more at: phys.org