Shiga toxin is nasty stuff. If you are infected with a Shiga-producing bacterium, like Shigella dysenteriae or some E. coli strains, there is no clear treatment: if you are given antibiotics, your infected cells will explode, spraying the toxin all over neighboring cells and exacerbating your symptoms. Each year, 150 million people are infected with Shiga-producing bacteria, which cause dysentery and food poisoning, and a million of those die. The lack of effective treatment for such Shiga toxicosis infections is one of the main reasons this year’s outbreak of E. coli poisoning in Europe was so deadly, with more than 3,700 people infected and 45 dead. But now scientists studying how the toxin makes its way around the cell have discovered that treating mice with the metal element manganese makes them resistant to Shiga poisoning. Since manganese’s chemistry is already well understood and it’s readily available, the possibility of using it as a treatment is exciting.

Here’s how manganese blocks Shiga’s spread, according to the group’s experiments in cultured human cells:

(more…)

In the Eastern Mediterranean, the pufferfish has arrived. And nobody’s too happy about it. The fish, also known as the silverstripe blaasop or Lagocephalus sceleratus, was first confirmed in Turkey in 2003 and has been spreading throughout the area. The problem with this unassuming fellow is that it contains tetrodotoxin, a neurotoxin that can be deadly to humans and for which there is no known antidote. Consumption of the fish has killed at least 7 people in Lebanon in the past few years, according to The Daily Star, and likely affected many more. A 2008 study found that 13 Israeli patients who ate the blaasop had to receive emergency medical attention at the hospital, where they didn’t recover for four days.

(more…)

Eating red meat could make your body more vulnerable to a dangerous bacterial toxin, according to a new study. A sugar molecule, Neu5Gc, found in beef, lamb, pork, and unpasteurized milk can attach itself to the cells lining the human intestines and act as a magnet for toxins produced by certain strains of E. coli, often carried in the same meats. The result is bloody diarrhea and sometimes death. “This uncovered the first example of bacterium causing disease in humans by targeting a molecule which is incorporated into our bodies through what we eat,” [ABC Science] says researcher Travis Beddoe.

The study, published in Nature [subscription required], was conducted in petri dishes using mouse tissues and human cells. The scientists tested human gut and kidney cells steeped in these sugar molecules and discovered that the toxin was about seven times more likely to bind to these cells if the sugar was present. It is still “not clear how to extrapolate this precisely to the human body,” [Science News] says co-author Ajit Varki. That is, researchers don’t know exactly what it means for human health yet. (more…)