MAR 07, 2018 07:43 PM PST

Immune Cells Use Bleach to Destroy Bacteria

WRITTEN BY: Carmen Leitch

Scientists at Ruhr-Universität Bochum have learned more about how immune cells use a toxic cocktail to battle bacteria. They determined that incredibly, chlorine bleach is one of the ingredients in the mixture. The proteins in affected bacterial cells get doused with reactive oxygen, causing the destruction of the bacterium. The findings have been reported in eLife

This is Kaibo Xie, Lars Leichert, Konstanze Winklhofer und Verian Bader (from the left). / Credit: RUB, Marquard

Cells of the immune system spring into action when bacteria enters our bloodstream. The most common kind of white blood cell, neutrophil granulocytes, are the first line of defense and can devour the microbes. After exposure to a toxic brew of chemicals including hydrogen peroxide, antiseptics, and chlorine bleach, oxidation alters the bacteria, killing it. While we know the basics of the process, many details are still unknown, leaving questions unanswered.

"Once we'll find an answer to these questions, we will understand how some bacteria outwit our immune system and how the immune system is impaired by certain genetic defects," explained researcher Lars Leichert, head of the research group Microbial Biochemistry. 

For this work, the researchers utilized recently created fluorescent proteins. They carry a signal that indicates chemical oxidation states. When exposed to blue light, these proteins, called roGFPs, glow green. If oxidized, they also glow under violet light.

The scientists used Escherichia coli bacteria that were engineered to carry genes encoding for roGFPs. After introducing these bacteria to immune cells, the bacteria was engulfed as the researchers expected. With a super-resolution microscope, the investigators saw that the roGFPs within the bacteria glowed after being exposed to blue light. After they had been completely devoured, it took only seconds for the oxidation of the roGFPs, which then glowed under violet light.

"Based on the speed and the specificity with which the roGFPs oxidized, we have deduced that chlorine bleach plays the key role in the process. That means immune cells utilize bleach to kill bacteria," concluded Leichert.

To find enzymes important to the mixing of the deadly cocktail, the scientists created cells in which certain enzymes were missing. It was found that when the enzyme NOX2 was absent, such altered cells couldn’t kill bacteria by oxidation. Myeloperoxidase is an enzyme necessary to generate chlorine bleach, and when it was blocked, there was also a marked reaction in oxidation.

Check out the following video from the research.


Sources: AAAS/Eurekalert via Ruhr-Universität Bochum, eLife

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
OCT 01, 2018
Microbiology
OCT 01, 2018
A Virus That can Help Ensure Water is Clean
It's estimated that 780 million people worldwide don't have access to clean drinking water....
OCT 23, 2018
Microbiology
OCT 23, 2018
DNA Pumps up Bacterial Cells
Cells are the basic building blocks of life, and have been well-studied since they were discovered in 1655....
NOV 01, 2018
Microbiology
NOV 01, 2018
Gut Bacteria can Have an Impact on Movement
One strain of gut bacteria can change how a fruit fly moves....
NOV 24, 2018
Microbiology
NOV 24, 2018
More Bacteria Found on the ISS, Researchers Stress Continued Monitoring
A check of the International Space Station (ISS) has revealed several strains of Enterobacter microbes....
DEC 07, 2018
Videos
DEC 07, 2018
A Common Pathogen: Norovirus
You've probably heard of norovirus before; it's a highly contagious family of viruses that can sicken large groups of people....
DEC 15, 2018
Cell & Molecular Biology
DEC 15, 2018
HIV Vaccine Successful in Non-human Primates
Researchers have been trying to create a vaccine for HIV, the virus that causes AIDS, for decades....
Loading Comments...