The interaction between amoeba and bacteria has long been a medical mystery. It is known that amoeba will consume various kinds of human pathogens, either destroying them or being destroyed by them, but the way certain amoeba interact with different kinds of bacteria has stumped scientists since they were first discovered. A new study conducted by the Baylor College of Medicine in Houston has shined some light onto the behavior of amoeba and bacteria.
Researchers used the social amoeba Dictyostelium discoideum to determine how they differentiate between various kinds of bacteria and what changes they undergo in order to achieve their destruction.
They put two classes of bacteria -gram negative and gram positive – together and then introduced the amoeba in order to see how it would respond.
“We found that the Dictyostelium did differentiate between the different bacteria,” said Dr. Adam Kuspa, professor of biochemistry & molecular biology at BCM and senior vice president for research. “In fact, it was shocking that nearly 800 different genes were activated when exposed to a kind of gram negative bacteria known as enterobacteria (Klebsiella).”
When the amoeba was exposed to different bacteria, various genetic sequences would become active, effectively changing the way the amoeba would function. With the gram negative bacteria, the amoeba activated genes used to degrade and destroy cell walls, while the genes involving metabolism would activate in the presence of the gram positive bacterial strains.
This study showed that all amoeba are related, so that which affects one will affect others in a similar fashion. The protein strains in each amoeba are very similar to those found in most mammals, meaning that this study could grant greater insight into the operation of the human immune system, which would be useful in both learning how to fight bacterial infection, but also in treating autoimmune disorders such as Multiple sclerosis and Rheumatoid arthritis.