Salmonella has nothing to do with the delicious pinkish fish native to the North Atlantic and Pacific Oceans. It is a type of bacteria that affects the intestinal tract, lives in animals and human intestines and infects them via contaminated food or water. 

Salmonella infection is usually caused by eating raw or under-cooked meat, poultry, eggs or egg products. Symptoms include nausea, vomiting, fever, chills, abdominal cramps, diarrhea, headache and blood in the stool. In some cases, the diarrhea caused by the bacteria can cause the individual to dehydrate so badly or the infection goes beyond the intestines that the condition is life threatening. 

Washing your hands thoroughly can help prevent the transfer of Salmonella bacteria to your mouth or to any food you’re preparing. Wash your hands after handling raw meat or poultry, using the toilet, changing a diaper, cleaning up pet excrement or touching reptiles or birds. 

Now, researchers from the biology faculty of the Technion-Israel Institute of Technology report that they have been able to inhibit biofilm formation in Salmonella bacteria. 

Biofilm – a resistant layer of microorganisms that form on and coat various surfaces – presents a serious medical and environmental problem because it protects bacteria and makes it possible for them to attach to tissues, medical devices, pipes and more. The discovery made by Associate Prof. Meytal Landau, doctoral student Nir Salina. Their lab research team expected in the future to lead to the development of innovative treatments that will inhibit the antibiotic resistance of virulent bacteria. 

In 2017, Landau’s team published an article in Science describing new type of bacteria that has become resistant to many types of antibiotics and that is responsible for a considerable number of infections in hospitals and in the community. 

The researchers discovered that this bacterium, which attacks the organism’s T-cells of the immune systems, does so in part by means of secreting certain fibrils. In an article published in Nature Communication in 2018, the Technion research team revealed their discovery that proteins from the same family as the toxic fibrils produce exceptionally stable amyloid structures that can survive under extremely difficult conditions and protect the bacteria

These toxic fibrils resemble amyloids, proteins associated with neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease but differ from them structurally. In their latest findings, the team revealed that proteins from the same family as the toxic fibrils produce exceptionally stable amyloid structures that can survive under extremely difficult conditions and protect the bacteria. 

In a recent study in PLoS Pathogens, the Technion researchers suggested that by interfering with amyloid fibrils produced by E. coli and Salmonella can hamper the bacteria’s defense mechanisms and their ability to attach to tissues and medical devices. This is accomplished by adapting for another purpose substances that have already undergone clinical trials for treating Alzheimer’s. The major advantage of this repurposing is that the approval process is much shorter and less expensive than in the case of a new compound.

Landau expressed the hope that these discoveries will lead to new treatments that will impair the fibrils and significantly diminish the aggressively virulent infections caused by Staphylococcus aureus.

The substances tested on Salmonella bacteria do not harm the bacteria directly but rather they damage the biofilm.The researchers believe that this approach of impairing the biofilm will reduce the risk of developing resistance compared to antibiotics that kill the bacterial and thereby induce defense mechanisms against the drug, making the bacteria more resilient and virulent.

The research examined the possibility of damaging Salmonella and E. coli bacteria found in contaminated food. But the researchers hope their discovery will also be effective in battling other bacteria, including Staphylococcus aureus. In his ongoing doctoral research, Salinas will focus on developing stable antibacterial substances and on examining small molecules that will interfere with the in-vitro assembly of amyloids in bacteria. He hopes these developments will accelerate the crucial battle against the development of virulent strains of antibiotic-resistant bacteria.


Source: Israel in the News