It has been discovered that the world’s deadly bacteria seek out and feast on human blood.
Washington State University (WSU) researchers have discovered a new trait called “bacterial vampirism” among bacteria like Salmonella and E. coli that cause foodborne illness.
It has long been unclear how and why these microorganisms can move so deftly from the intestine into the bloodstream, where they can be deadly.
The team discovered that these bacteria are attracted to the liquid part of the blood, or serum, which contains nutrients that the bacteria can use as food.
Pathogens can easily find where the serum is and enter the bloodstream through small breaks in the digestive system, sometimes leading to death from sepsis in people with inflammatory bowel disease.
Even the smallest amount of blood is enough to attract vampire bacteria, much like sharks with their famous ability to detect a drop of blood in 10 billion drops of water.
Co-author Arden Baylink, a professor at WSU’s College of Veterinary Medicine, said in a statement: “Bacteria infecting the bloodstream can be deadly.
“We learned that some of the bacteria that most commonly cause blood infections detect a chemical in human blood and swim toward it.”
According to the new study published in the journal eLife, enterobacteria like E. coli and Salmonella can detect as little as a femtoliter of serum – a tiny amount equal to 0.0000000000001 milliliters.
Once they find the cut that causes blood to flow into the intestine, they gather around it and enter it.
This is a lot like how sharks can search for prey using their blood, but bacteria don’t have noses and so rely on other senses.
The team used a high-powered microscope system to simulate intestinal bleeding by injecting microscopic amounts of human serum and watching the bacteria move toward the source.
They watched the microbes search for the serum and found that it took less than a minute.
In this case, it’s a strategy called “chemotaxis,” in which bacteria move toward higher concentrations of specific substances.
The team also determined that Salmonella has a special protein receptor called Tsr that allows the bacteria to detect and swim toward serum.
When Tsr was discovered, researchers used high-resolution microscopy to visualize the protein’s atoms interacting with serine.
Scientists believe that serine is one of the chemicals in the blood that bacteria detect and consume.
This new understanding of how bacteria can take hold in the bloodstream paves the way for new drugs that will prevent sepsis before it even occurs, rather than treating it once a person is sick , said the scientists behind the new study.
“By learning how these bacteria are able to detect blood sources, we could in the future develop new drugs that block this ability.” These drugs could improve the lives and health of people with inflammatory bowel diseases who are at high risk of blood infections, the doctor said. student Siena Glenn, co-author of the study.
Usually, intestinal infections are resolved by the immune system without serious problems – perhaps a touch of diarrhea.
But people with inflammatory bowel disease, including Crohn’s disease and ulcerative colitis, are at much higher risk of developing bleeding inside their intestine, which can leave bacteria enter the bloodstream, causing a more serious bacterial infection.
This puts them at particularly high risk of developing a condition called sepsis, which is essentially a chain reaction of the immune system attacking the body in response to an infection.
Understanding exactly why gut bacteria are able to enter the bloodstream through tiny tears or cuts in the intestine can help scientists prevent serious illness in people with these chronic conditions.
Under normal circumstances, our gut contains populations of bacteria that are often considered harmful, such as E. coli and salmonella.
They are controlled by other bacteria and by our immune system when we are healthy.
But if they get into our blood, they can cause sepsis.
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Gn Health
