Health and Wellbeing

 

Vampire bacteria feed on L-serine in the Human Blood and Cause Infections

Bacterial infections can lead to various life-threatening conditions such as sepsis and bleeding in the gut. Recently, scientists have found that the disease-causing bacteria can also enter into the blood and cause deadly consequences.

Scientists at the Washington State University and University of Oregon reported some interesting finding and called these bacteria as “Vampires”. They have utilized three different members of Enterobacteriaceae family (Salmonella enterica, Citrobacter koseri, and Escherichia coli) in these experiments. Bacteria were cultured and minute amount of the blood serum was provided in the cultured plates and it was observed that bacteria rapidly moved toward the serum and reached there in less than a minute. This behavior is known as chemotaxis and main chemoattract in this case was an amino acid, l-serine that is widely present in the blood.

Bacteria mainly interact with l-serine via tsr protein also known as chemoreceptor. Scientist have monitored the interaction between tsr and l-serine for the first time via high resolution microscope.

Tsr receptor is conserved in almost all the bacteria of Enterobacteriaceae family and other pathogenic bacteria that cause blood related infections. Therefore, it is very important to understand the mechanism behind bacterial entry into the blood stream and its interaction with l-serine, to effectively block this association. Moreover, it is very important to know that “why these bacteria are attracted toward l-serine and not the other amino acids”.

These findings are very important and will help to develop the drugs that could stop this interaction and prevent the bacteria from entering into the blood stream and thus causing the deadly infections. Gut residing bacteria usually enter into the blood when the gut lining is disrupted due to disease conditions such as inflammatory bowl disease. Therefore, it is very important to prevent these diseases at the first instance by adopting healthy eating habits.

 Reference

Glenn, S. J., Gentry-Lear, Z., Shavlik, M., Harms, M. J., Asaki, T. J., & Baylink, A. (2024). Bacterial vampirism mediated through taxis to serum. bioRxiv: the preprint server for biology, 2023-07.